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Turboschpeck
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Why small rooms kill low bass?

When I had a stereo system in a small room (9x7 feet) I couldn hear anything below approx. 70 Hz.
Later I switched to a room (with the same system) of 9x9 feet and I could hear down to 50 Hz.
The rooms had no furniture, only foam damping on the walls.
Are standing waves killing the bass or something else?
Keep in mind that even cheap headphones can easily produce 30 Hz with 0,5 inch of air space!

Bill B
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problem

Yes, quite possibly, standing waves made your bass problematic, and may have caused relative nulls or cancellations at certain frequencies.  If your speakers are capable of below 50 Hz response, you would have heard the low bass if you put your ear next to the speaker, like a headphone.  Moving the speakers and/or your listening position in a room can make a difference.

Turboschpeck
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Small rooms big waves

Thanks for answer Bill B.
I found complete answer thanks to Ethan Winer.
 

"There is a common myth that small rooms cannot reproduce low frequencies because they are not large enough for the waves to "develop" properly. While it is true that low frequencies have very long wavelengths - for example, a 30 Hz wave is nearly 38 feet long - there is no physical reason such long waves cannot exist within a room that is much smaller than that. What defines the dimensions of a room are the wall spacing and floor-to-ceiling height. Sound waves generated within a room either pass through the room boundaries, bounce off them, or are absorbed. In fact, all three of these often apply. That is, when a sound wave strikes a wall some of its energy may be reflected, some may be absorbed, and some may pass through to the outside.

When low frequencies are attenuated in a room, the cause is always canceling reflections. All that is needed to allow low frequency waves to sound properly and with a uniform frequency response is to remove or at least reduce the reflections. A popular argument is that low frequencies need the presence of a room mode that's low enough to "support" a given frequency. However, modes are not necessary for a wave to exist. As proof, any low frequency can be produced outdoors - and of course there are no room modes outdoors!

Here's a good way to look at the issue: Imagine you set up a high quality loudspeaker outdoors, play some low frequency tones, and then measure the frequency response five feet in front of the speaker. In this case the measured frequency response outdoors will be exactly as flat as the loudspeaker. Now wall in a small area, say 10x10x10 feet, using very thin paper, and measure the response again. The low frequencies are still present in this "room" because the thin paper is transparent at low frequencies and they pass right through. Now, make the walls progressively heavier using thick paper, then thin wood, then thicker wood, then sheet rock, and finally brick or cement. With each increase in wall density, reflections will cause cancellations within the room at ever-lower frequencies as the walls become massive enough to reflect the waves.

Therefore, it is reflections that cause acoustic interference, standing waves, and resonances, and those are what reduce the level of low frequencies that are produced in a room. When the reflections are reduced by applying bass traps, the frequency response within the room improves. And if all reflections were able to be removed, the response would be exactly as flat as if the walls did not exist at all."

Reed
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I agree with speaker placement

I agree with playing with speaker placement.  I have planar speakers.  I moved them further AWAY from the side and front walls and got considerable better low frequency performance....which is contrary to the way I thought things worked.  There is more going on than I obviously understand, but I can tell big differences with speaker placement.

Also, after a while of playing with placement, I stop and come back at it in a day or two.  You can drive yourself mad after a certain point. 

michael green
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My take might be slightly different

I don't like the sound of hard rooms, never did. At the end of the day harder rooms with over damped materials in them leave lots of music on the cutting room floor. My one listening room is 9 X 9 and easily goes into the twenties no problem.

Keep in mind sound is vibration, and if the room is not able to reproduce vibrations your not going to hear them. Also if you dampen the room to the point where you are only hearing what's coming off of the cone that's exactly what the music will sound like, "a cone" and the body of the musical notes will not be fully developed.

For many years I have had to go in and rebuild rooms that were extremely over built. It's an embarrassment for the client to spend all that money to only find that what they ended up with was frequencies and not music reproduction.

There's a reason why musical instruments are built to vibrate. They are built to vibrate to create notes and harmonic structures. Your room should do the same. In our factory we never put the listener in both, our dead room and our tuned room (which was more live) and had them choose the dead room, ever.

It really comes down to this. You can listen to a system that has 90% of the music missing or have a system that is full of dynamic range and musical involvement and a stage that goes why past the walls and never points at the speakers placement. I find that most of my clients are transitioning from the audiophile "dead" sound to a much more musical experience. Their rooms and systems become more like the instruments being played live and quite honestly you would not like the sound of an instrument with a bunch of dampening shoved in it.

I would encourage any listener to listen to a tuned room and compare it to a dead room and see which one suits their taste.

geoffkait
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Room acoustics and foam

I'm pretty sure everyone has seen pictures of recording studios and monitoring rooms with wall to wall Sonex acoustic foam.  I'm here to tell you that even a little bit of Sonex in the room will hurt the sound, and a lot of it will kill the sound.  Sonex is one if the biggest "frauds" ever foisted upon unsuspecting audiophiles.  

 

Geoff Kait

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michael green
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Room Acoustics and Foam

Foam, and I would include many types of cloth are sound dampeners, music destroyers. It is shocking how many bad sounding acoustical products are out there. What's more shocking to me is that some how many audiophiles are not able to recognize the ill (side) effects of these materials.

I think the sad part to this story is that many listeners have been taught that deleting sound makes sound, and that materials delete sound. This couldn't be further from the truth. Some how (probably through lack of experience) we have been given the information that we can put something in the room and it disappears sonically. We need to start to understand that if something (anything) is put in our room it becomes part of the sound, and that even though a material may indeed burn sound by converting that sound into heat it leaves it's own signature in the musics presentation.

If we walk into a room that sounds dead, you can bet part (usually a big part) of the music is missing. I've hundreds maybe thousands of times have had to go into rooms (you can read this in Stereophile reviews) where we started off our listening by taking things out of the room to bring the room to life. It's after the room has some energy to work with that we come back in to voice (tune) the space. The absolute trick to great sound is what the room sounds like on it's own, how a speaker mates with that room, and how to treat that room with as little as possible to not create a signature that is out of balance caused many times by "products" that are overly absorbent or diffusive.

We as audiophiles love to hang on theory, and talk of numbers, charts and graphs but these do not create musical notes. Sound pressure creates musical notes and tuning that sound pressure in a balanced manor with an understanding of acoustical amplification is what makes great sounding systems.

For myself I love creating great sounding rooms and many times they look nothing like the typical audiophile setup when I am done, but more like a private mini concert halls. The right amount of tonality and the added in flavors that the listeners favors.

I think maybe the biggest problem we have in this hobby is that many are not taught to detect when their system is acting correctly or not. The buying public is talked into buying product when they should be buying sound. They're not only living with the wrong stuff (total system many times) but are thinking that because something works for a writer or club or friend that it will work in their own place, and this is way off from reality. The reality is you can't force a system to sound good if it is out of tune with the rest of the system. $$$ has nothing to do with it. It either works or it doesn't, and I see many trying to build their lives around things in their systems that just don't sound right for their environment many times. We hate to hear these types of things but if you have been doing this a long time and are still not where you want to be, you should look at why and correct it. There are easy ways to hear if your system is not working, and there are equally easy ways to correct them. I say easy but that really depends on the individual and what they have to work with. And many times how long they have had their system in reverse and the pride they may have to give up to put the system in drive.

Bill B
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first reflection point

I use homemade panels at the "first reflection point" on my sidewalls, understanding that that is widely recommended.  Michael, what do you think about that technique?

michael green
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first reflection

Hi Bill

1st reflection has become a popular acoustical tweak, but it's really not all that science bassed. I cover a lot more of this on tuneland but the nutshell is, waves in the audio range esspecially the lower you get don't travel in a straight line like you see in a lot of charts showing waves bouncing around the room. At RoomTune we did a lot of testing on how acoustical waves work and never found the soundwaves we listen to in our rooms to travel like a lot of people in the audiophile or acoustical engineer world came up with. What we did find is that the room builds pressure and this pressure I have called laminer flow (the sound traveling along the walls) and pressure zones (the pressure areas that build in a room).

here's a link to tuneland that covers what we have found

http://tuneland.techno-zone.net/t200-understanding-acoustical-pressure-zones

When looking at this you will see tons of places in the room to explore. The thing to be careful about in the area that many call the 1st reflection point is it's very easy to lose musical information by killing the harmonic structures in the developement stage of the air born signal. I am not crazy about the idea of getting rid of the sound, I want to instead use the room to shape it. I also am very careful about absorption. It takes very little material to soak up sound to the place where the material becomes a negitive. This is why I did something a little different from the other guys when making RoomTune and now the few other lines. When I use dampening, it's as a barricade and not direct dampening almost always. If you look at the design it's made to have something between your ears and the dampening. This is why you see a, what we call, live side to the pillows and a tuning board for the more advanced products. If you have a product that you have made and the dampening is facing you directly or the speaker it's sucking up the sound instead of controlling it.

Here's something you might want to play with. Put a thin card stock or something on the front side of your acoustical panel you made. If the right material you'll hear the sound clean up. And if done correctly you'll have more of the sound waves burned but without interfearing with your sound purity.

Here's where a lot of folks get stuck. They treat their room but they lose dynamic range and their room and music sounds dull. Nothing worse than music with a blanket over it.

Basically here's the trick. You want the sound waves to form. After they do you then stop them before they cause too much build up. Look at a RoomTune placement guide and it gives you the basics, but keep in mind this is just the starting point and every room sounds different and (this is very important) every speaker loads a room slightly different.

I spend a lot of time helping people find out if they have the right speaker for the room and what type of treatment is right for them. Rooms are not one size fits all, and acoustics (the biggest part of the chain) usualy is the frustrating after thought, but this doesn't need to be so. Once you know the tricks to room setup it's actually not that hard.

So as far as first reflection, there are some important things to look for and listen for before making the decision to play with something so close to the speaker itself, and in most cases you may not need nearly as big acoustically products as are being pushed. A little in the right place, with the right desgn, does a lot more than a bunch all over.

audiophile2000
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Simple Explanation on Room Acoustics

To start out, room acoustics can be very complicated subject, but luckily it is one of the few in this hobby that is 100% governed by science and formulas. Now I didn’t say the formulas were easy or something we all need know but its nice to know that this has a solid scientific foundation and there are a number of text books and college level classes on it if you are really interested. To be honest you really only need to know the basics to get by and basics of sound treatment come down to absorption and diffusion, speakers placement and seat placement in the room. There a couple of quick and basic items I found over the years that really have helped to make this stuff simple. Also most acoustic panel companies will have an audio engineers/acousticians on staff that you can speak with to help solve issues, funny though most of the initial recommendations are very similar at first.

 

Basics for speaker setup.

 I can stress this enough. If you haven’t measured the distances from the listening area and made sure everything was equal distance and the same angle you should do this. I would recommend using a laser point and a laser measure as it just makes things easier, but making sure both speakers have the same angle and distance from the listening area is critical to proper imaging. From there move you speakers closer to the wall for more bass (“boundary interaction) and out for less. You can also look at the distance between the speaker, the closer together the stronger and more focused the center image is, the further apart the wider the sound stage so it’s a balancing act. I normally start with an equilateral triangle and adjust things from there. Also I normally you want to have your seating area  a few feet off the back wall and typically you will hear 30 to 40% into the room from the back wall is a very good place to start. The big key is not right on the wall if you can help it. You will soon find that this is all a big balancing act so plan on playing around for a bit to get it right, its well worth the time. 

 

Once you have a decent placement take a look at acoustic treatment. Someone once told me that you would prefer a deader room up front where the speakers are and a livelier room in the back where the listening position is. Why dead up front, you want to control the early reflection points an boundary interactions. Basically you want to first sound you hear coming from the speakers and not a reflected sound from the wall next to them. (also good to treat side early reflection points as it will help stabilize the image. From there move on to the back of the room. Depending on your room size you will have a combination of diffusion (scattering the sound to make the room seem larger than it really is) and absorption to control sound build up. For smaller rooms or rooms you are sitting close to the back wall it will be heavily absorptive as you need some room for diffusion to work (again it this physics thing here). Now in a lot of set up you will also see panels on the ceiling or a “cloud” above the listening area and this is due to the fact that your room is 3d (you have 3 axis (length, width and height) and correctly treating all three will give you the best sound. Also a good FYI on absorption is that basically the panel is converting sound (pressure wave) into heat (the insulating material in the panel). As you guessed it, the longer waves need more material to absorb them so the thicker the panel the lower frequency it can treat (funny thing is the lower waves also require more energy to move the driver – hence the more energy you need to dissipate). In general acoustic foam is really to treat the high frequencies as it really doesn’t have the mass to do anything to the low frequencies (again no magic here, just physics). Also sounds tends to build up in boundaries which is why you see corner traps recommended so often as you have 3 boundaries meeting there so it’s a good place to spend money on. As always its good to add slowly and see how things progress as it is possible to go to far as you need some reverberation in the room to make the music come alive and fill the room (the reflected sound is important, you just need to control and make sure its in the right place).

 

There are a number of good video’s on the subject (GIK (panel manufacturer) has a couple of great intro video’s on thier website, there are also a ton of videos on the pro audio side). There was a few DVDs with the title getting better sound that really helped me dial in my room.

 

Just wanted to post this after reading the complicated post some people were making as this truly will do more than any audiophile tweak at a fraction of the cost. I’ve tried a lot of the tweaks and some seem to help some don’t but this is actually something that will improve the sound of any system. Lets just say you can even hear the difference when you are carrying on a conversation in the room.

michael green
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play the room

Hi 2000

I would disagree about a lot of the formulas. The formulas for a big part are what have made it difficult for listeners. I can not tell you how many times I have had to correct acoustics for studios and homes and halls alike because the person in charge was stuck in formula hell. The very first rule in acoustics is, no two rooms sound the same. Second, no two systems sound the same. Third, your system will sound like your room.

We have used in our facilities and in homes all over the world the "audiophile" formulas and have had less than favorable results.

For example, here's one simple test

Take two loudspeakers of different design/size/weight/mass and apply the formula suggested "almost any audiophile acoustical formula will do" and you will not have these different designs react the same. I have a formula that I like to use, but the truth of the matter is everything in this hobby responds differently than everything else. We need to treat this hobby with the same care that we do musical instruments and the music they produce.

I could walk in one of my listening rooms right now and do the setup you suggest (LEDE) and the first thing I would notice on Abbey Road, hear come the sun king, is that the crickets and frogs would come almost directly out of the right speaker float maybe 3 feet deep across the stage and end close to the left speaker. Why would I want this if I could have the crickets start some 10-20 feet past the right speaker, outside the room, roll through the stage at 10-15 feet deep and out the other side of the room 10 feet past the left speaker? While this is happening also being able to hear how big the area was where the cricket part was made.

I would much rather tune my room so that one, I could create a full balanced stage, and two, have a room so that when a new recording is put on with a different vibratory code I could make an easy adjustment to allow the stage to do it's magic.

I thing that has always bugged me about this hobby is the audiophile world has limited their reach to a very small stage, that is not very life like. I do understand completely that many struggle to get a basic stage and smallish at that, but there is a far bigger world to be heard. Once you hear a stage that is really 3D it is hard to go back to the typical.

geoffkait
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Speaker placement

No matter how much you have in the end you would have had even more if you had started out with more.  The dynamics of acoustic waves in the room is very complex, therefore one should give serious consideration to using the XLO Test CD to obtain optimum speaker location, the primary track of interest being the Out of Phase track.  This track allows for precision placement of each speaker INDEPENDENT of speaker type/manufacturer, room dimensions and room treatments.  If one attempts to locate the speakers by ear, the best he can do is find local maximums, whereas the Out of Phase track on the XLO CD will help find the absolute maximums. 

 

Geoff Kait

machina dynamica

michael green
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setting up speakers and making a soundstage

A big part of this too is how many times you've setup speakers before. For myself it's far easier to do placement by ear. If I'm doing a show for example, I'll pick out the music I want to use for the mood then let the soundstages of these pieces of music be my guide to the setup.  This also helps me because if someone comes in with a recording that has a different signature it only takes me a few minutes to make any adjustments I want to. That's of course for basic listening, but I find that many of my clients want to go much further than the typical soundstaging. They want the music to play the system and not the system play the music. There's a big difference.

I have found that there are levels of listening, one being a basic setup, but there are levels that go way beyond this. Most of the guys I listen with you would have a hard time pointing to the speakers in the room, whether you were standing, walking around or sitting in the sweet spot.  Over the years I've had a lot of fun watching people get up out of their seats and walking up to the speakers and having to put their ears right up to the drivers before believing these speakers were playing. To me, that's when your approaching a high level of listening, and also to me this is what I would call "high end audio".  I've met hundreds if not thousands of hobbyist over the years who are frustrated by never getting to first base in their listening.  We'll pick out a piece of music and compare our soundstages, and they say "how did you do this".  In most cases as we explore their setups we find things in their systems that are blocking the music signal, that's one, another is they are not understanding their room. 

an example

Build two rooms with the exact same dimensions (we did) and make one out of two layers of drywall or harder materials and the other with more flex to it. Run the same test in each room and the results will come out completely different.  Lets go a step further. In this example lets use the same room.  Run your tests then put the test equipment in the refrigerator for an hour, and run the same tests, results are different.  Change the humidity by 20% and the results are different again. Add a chair to the room, different, and so on. I apperiate that companies have made guides for you to play with, but the bottom line really does come down to how well you know your system and music. 

The more you learn how things work by you listening the better the end results will be for you.  When someone contacts me about acoustics I ask for their whole system, where they are located and the build of their room (the build of their room being more important than the dimensions of it).  How a room responds to pressure is the number one factor in the reproduction of sound I have found. Charts and tests are cute but really don't say what music is going to sound like when you are sitting there listening. For one your ears measure completely different than the microphone you are using to do testing with.  Second, if your going to do tests you should be doing them (we did) on the entire room and not just those few places that have become the "audiophile or studio engineer" hot spots. When we did we found that there were a ton of myths floating around that have somehow become accepted as truth, making it more difficult to achieve a higher level of listening. It's great for engineer types but if your going to have the music appear in front of you like at the place of recording your going to have to pick up the art a little more than testing tools and myths.

another pipe filler

A couple of post ago someone said that to burn lower waves you need more material, this is not entirely true.  To properly burn lower  waves you need to first find where they are being stimulated from in a room, then find the material and amount to control them with. It could be as big as a 2 x 4 panel but it could also be as small as a few inches by a few inches used in the right spot in the room.  But before we jump out of our seats to go treat we need to realize a couple of things. One, how does it sound in your room in general, and we must keep in mind that as soon as we change the piece of music to something else the waves change in the room along with the rooms pressure.

All of this comes down to, how far do you want to go as a listener. I run with a group of guys who I would call the extreme of the hobby.  These guys have soundstages that put your jaw on the floor and give a new meaning to 3D listening. Their systems are tools and very little is "stock". Some have "tunable rooms" that have adjustments on the walls/floor and ceiling every 16" on center with the wood used for studs cured like musical instruments, that's advanced listening and what I consider high end. If you took the average acoustical product and set it in one of these rooms it would stick out like a sore thumb.

another point

I don't want to give the impression that I am down on the XLO product, but I would like to say that if you find a wonderful balance to your signal path and your acoustics you can play with staging and placement and are not tied to a one placement setup. I say this because some people I have found want to look at a stage, or right in front of them or even in the middle of the stage. There are many different types of stages and it really comes down to your taste and once you find the balance throughout your entire signal pathway, many things that you may have had problems with or thought you would have to live with disappear. So as much as I would say yes the XLO gives you one flavor, there are also other flavors to be had. To me, finding your flavor is the right flavor.

BTW, even though I do take a little different approach than Geoff, it's great to see people on the threads here who are pursuing the art form of listening. When I see someone who has taken the time to design and use products that have a different view than "kill the sound" it makes me smile. It would be great someday if the shows would be more about getting great sound through the tools and the eyes of the tool designers.

audiophile2000
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Follow Up

Michael,

I don't disagree that there are number of items and changes that need to be made on a room by room basis. I was more simply stating that room acoustic does not have to be this magical item when there are some very basic items that most engineers will suggest and will get you leaps and bounds closer to a good listening room. Also as you said, building material and construction do make an significant difference in the room, but the truth of the matter is that people have very little control over those and as such many are stuck with real world solutions. For instance, I live in a high rise building and as such have drop down ceilings, and it happens to be that the ceiling resonates in the 60 -70hz (not good). Now I should really remove the ceiling and rebuild it with other materials but as it is a rental that would not be very practical so you end up with moving the seating position around and making other changes to the room to make it the best it can be. The issue is, outside a recording studio or custom designed room, you have real world problems.

I should also highlight that most of my attention on room acoustics has come from input from people on the pro audio / recording side and while its true there is no one stop solution as the interaction of sound in the room is quite complicated, but there are a number of simple solutions that will improve most systems when compared to a untreated room. Should also highlight that mixing rooms in a studio are designed to accommodate a number of monitors as you will typically want to listen to a number of set ups to make sure the mix is translating well.

my post was basically to try and encouraged people that have never used room treatment to try it as I think you will agree it is likely one of the best upgrades you can invest in. Will highlight that while it doesn't get a lot of attention in the Hi-Fi world (or as much as it should in my opinion), there is a large focus on acoustics on the recording side where our hobby really begins.

I guess as a follow up to you, what would recommend to people in smaller room to normal size rooms as the basics of what they should start with for room acoustics. I have taken a very pro audio approach that is very focused on monitoring and hearing what is on the mix (i.e. my focus was not only to hear the music but to dig into what the engineer was doing on the track so controlling reflections and hearing direct sound was very important)so it would be interesting to hear a different perspective.

michael green
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high end acoustics

Hi 2000

We are for sure heading in the same direction encouraging listeners to make their rooms the priority. It is what we hear, and no matter what we think we are listening to as far as all the other parts to our audio systems the room is the deciding factor of how things really sound. As much as I take up my arms for the industry to go simple (we have way over built our components) I recommend that we make high end acoustical products that work in all rooms and not fill the rooms (recording or home) with dampening causing distortion.

In the pro world there are many lost souls as there are in the high end audio world, but this only means to me that we have a bright future in developing and training people how to listen and what to listen for.  Both high end and the recording worlds have the average approach and the extreme. We don't see this extreme world as much because it takes an effort and we live in an instant society. Throw it in, turn it on and blame something else if we don't like the sound.  Our studio control rooms are so bad that hardly anyone uses them for a playback. This should be concern number one, number two is I have been to many, many mastering rooms that are a mess. The same problems I have been adressing in high end audio are all over mastering rooms, and again we find these guys sitting in cars or other rooms to make final decisions.  Doesn't it seem odd to anyone else that we don't like the sound of our control rooms so we send it to the mastering room, and we don't like the sound of our mastering rooms so we send it to a car or home, and we don't like the sound of our homes so we say "this must be the way they did it in the recording".  What I'm saying to all of us is "we are still babies in this". As good as music sounds in our playback at home we have not yet learned one of the fundamentals of audio. It's tunable! I too lived in high rises and they sounded fantastic, ask my visitors and look at THE Show report 2005. This penthouse knock their socks off, so did my penthouse in Manhattan. How and why? I made my systems tunable and after tuning in the electronics, mechanics and acoustics  I could pretty much create any sound I wanted.

Here's what I basically don't get about high end audio. Why call it high end if we're only going to take it to the equipment side of high end? We spend all this money on the plug and play part and leave out the mechanical and acoustical parts as if the components are going to do the other 2/3 of the sound. Never gonna happen as you will agree, but to me it seems silly to spend money on these over built boat achors that squeeze the music, trading them like baseball cards trying to come up with the right combo of something that will never replace the sound of the mechanics and acoustics of the room. It also makes no sense to kill the room further in the same attempt. What we need to be doing is finding out how sound really works in a room www.michaelgreenaudio.com for starters and make tunable products that allow the listener to simply tune in the sound they want. This way for those who want to say absolute they can and for others who want their own taste they can as well.  We split hairs over being right and wrong while we are listening to maybe a tenth of the recorded source. Stephen just wrote an article on "The entry level #39" . It talks about headphones in the first part. I'm really surprised that people can sit and listen to their system in their room and then put on a set of headphones and not have a ton of soundstage questions. There are talks about what is right or wrong but they don't talk about the reality of the soundstage itself. Truth is the typical audiophile room soundstage is way off from the actual recorded soundstage.  I'm not saying someone has to listen to the real stage, but what is being heard in the average high end audio system, in the average high end audio listeners home,  is not all that close to the actual recording. If we don't call the headphone soundstage correct, than souldn't we be fixing headphones? And more importantly, if we do call it correct shouldn't we be looking at why we are listening to this tiny stage between our speakers in our home listening rooms? I have heard audiophiles debate this "which is right thing" but none of them have taken the time to create a real soundstage in the listening room, not really. My point is the room is a frontier that is just barely being scratched, like wise is the mechanical. We had our first round or two in the fight, but there are more to go if we want to call ourselves truly high end audio seekers. One of the things that will have to be looked at is the over doing it, not only with our build of equipment but also our acoustics.

Let me ask you a question. Why is the ceiling resonating at 60-70hz not good? Second question, how are you measuring that ceiling? I'm not trying to be a smart A here, I'm asking because many people don't understand that they need a room to vibrate to reproduce sound. If your room didn't vibrate you would hear a terrible elongated echo and canceled waves and a lot of other problems. Do you know how many times I get a call from an angry audiophile asking me what they did wrong? It's unbelieable that you guys have not lined up these acoustians and tweak makers and shot them yet lol. If I hadn't taken the time and money to build these test rooms over the years and traveled around the world listening and having people experiment in their homes, studios and testing rooms all over the world I would be blowing smoke, but because I did and tested them correctly I have learned so much about what is going on with the acoustics and mechanics in a room and around a room that I have an understanding of the practicality of what is going on that flies in the face of what people are not only being taught but what they are buying, using and not getting the correct results from.  I could tell you about a tunable acoustical device that you could set in your room and fix it along with a mechanical one that would change listening for you and any one else reading  this, but it wouldn't be based on killing vibrations or acoustics. Instead it would take the vibrations of your room and equipment and electric and tune them.  You see once you tune something the distortion goes away. If you kill something you are only causing more distortion. It may sound tighter when you kill, till you hear the missing frequencies or distorted notes, but if you tune you will get both the notes "intune" and the tighness.

So I do totally agree that people should learn how to treat their rooms, and hopefully if they get on the right track before heading down the world of dead they will find more to their music, then needing to go down a road and come all the way back to start again.

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room acoustics

It's funny how many of us try to solve our room issues with our electronics or cables or speakers. I have an excessively live sounding listening room because of a high ceiling and very hard walls and ceiling that don't flex or absorb much sound energy. On it's own it reminds me of a subway station (ok, not that bad), with lots of annoying reverb/echo that doesn't serve the music and will give me a headache after a while listening. I've had Michael Green audio Roomtunes in the corners of my listening rooms for about the last 20 years. But these weren't enough to tame all the distortions going on in this room. So I made multiple investments in "upgraded" gear -- a Lamm preamp, NOS tubes, top-of-the-line AudioQuest interconnects, Black Diamond Racing cones and pucks, a variety of damping tweak products. Eventually my system got "cleaned up" and sounded very "clear." It had a pristineness that I thought I was looking for. Except I lost interest in listening for hours at a time, as I used to do. The system had lost the ability to give life to my music. There was something fundamental (or harmonic ;) missing.

Years ago I was in Las Vegas and visited Michael Green in his home. He had three systems set up in different rooms. After just a few minutes of listening to his very basic nearfield bedroom set up with his acoustic treatment products on the walls in various places, I blew my paradigm of what a system could sound like. There was so much musical information, it almost felt hallucinogenic (I know that seems extreme, but that's what I experienced). The speakers were almost against the wall and the bass went very low and was really visceral. That experience also helped me realized how much musical information actually exists in a recording. He also had a livingroom set up with a dvd player and big screen tv. I watched and listened to a Roger Waters concert DVD in which he was playing Pink Floyd music. There my ears were bombarded just as if I was in front of the stage a little ways back. Totally surrounded by sound and spatial cues, and everything was clear and integrated. I didn't want to leave it was such a revelation.

So now I have a much simpler system in my listening room without any damping devices, have more room treatments that control the problems created by the hard surfaces and loose floor boards, and can get a soundstage that extends beyond the walls of the room if I want it. Music sounds more real and I can hear lots more in a recording than I could hear before in my highly damped high end system. And I don't get fatigued or bored anymore.

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Small room pressure issues
Turboschpeck wrote:

When I had a stereo system in a small room (9x7 feet) I couldn hear anything below approx. 70 Hz.
Later I switched to a room (with the same system) of 9x9 feet and I could hear down to 50 Hz.
The rooms had no furniture, only foam damping on the walls.
Are standing waves killing the bass or something else?
Keep in mind that even cheap headphones can easily produce 30 Hz with 0,5 inch of air space!

Low frequency energy is all about the length of the wave and will it "fit" into your room dimensions and associated volume. Lets look at a 30 cycle wave which is ~ 37' long. How is this long wave going to fit into your room size. The real answer is that it will not.

Knowing that, you need to determine just how uncomfortable a "fit" is made in your room. You can realize the nature of its unhappiness by viewing a frequency response curve with the associated modal issues. Peaks and troughs in the response curve is your room telling you just how much it dislikes that particular wavelength.

Treating these unwanted pressure issues then becomes a matter of selecting the appropriate low frequency technology of which there are three main types: Helmholtz, membrane, and diaphragmatic. Choosing the correct one and then locating its position within the room requires experience and understanding of the strength of the unwanted pressure you are facing and its position within the room. Sometimes it is best to look at making the room smaller, sometimes finding a new room with different dimensions and volume is required.

Dennis

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from what we have tested

You don't need to hear a wave at it's full length to hear the note. You can get 30 cycles easily in a small room, do it all the time.

What makes a difference in the low notes in a room is how the room reacts to the pressure physically.

Sound pressure and sound waves are not straight lines, their also not wavy lines, Their spheres of pressure that move in all directions. People get hung up on lengths, but if this were true you would need a room 37 x 37 x 37 to get the cycle.

Let me give an example how measuring can get a person in trouble. You set your test mic in the room right? Your mic is not 37' from the source. How is it then picking up the cycles? If using end length was a legitimate formula the mic would not be able to pick up any sound unless it had reached it's end length. There are tests run all day long at one meter as a standard. How does a mic pick up those lengths that are longer or shorter than the mic position if a cycle needs to extend to it's full length to be heard? If a cycle can not be heard at any length along it's way to maturity than it would only be able to be heard at it's end length, and thats just not how it works. Cycles are cool for a measurement but when you use the numbers to guide your listening your screwed.

It's always been interesting to me how many people get involved with the numbers side of the hobby but when this doesn't measure up to reality it's time to listen and rethink how things really work. This industry is based on measuring a lot of times when it should be based on doing, and there are tons of folks who have not spent enough time in the doing department. I'm not suggesting that's you Dennis, but I am saying that if something happens, like low bass in a small room which happens all the time, maybe we should be looking at the reality of the actual sound and figure out how that happens rather than saying it didn't or can't, cause it clearly is and does.

I think we should be doing things first then measuring what we did for people who need specs, but doing it the other way around only opens up dabate.

michael green
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Tested

Kind of glad to hear you say that Michael. I've spent most of my audio life listening to music and tuning by ear. The technical and measured aspects always seemed a trifle boring to me.
I'm sure you get a gut feel as I do by just walking into a room, talking, clapping hands etc without hearing music or measuring frequency responses.

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Low frequencies in a small room

The most extreme case would be the Schumann frequency generator that is an audiophile device that produces a 7.83 Hz electromagnetic wave. Now, aside from the while issue of why the Schumann frequency generator might improve the sound the reason I bring this device up is because of the frequency 7.83 Hz. First, a quick definition of what the 7.83 Hz frequency represents: the Schumann frequency is the natural resonant frequency produced by lightning storms and other electrical phenomena in the trough of the ionosphere around the Earth. It is that same electromagnetic wave that's being reproduced in the listening room by the Schumann device. So, you might ask how long is that 7.83 Hz electromagnetic wavelength? Well, the reason the frequency is 7.83 Hz Is because it is determined by the circumference of the Earth, I.e., the resonance of 7.83 Hz occurs in the waveguide of the ionosphere, which is about 25,000 miles long. Thus, the Schumann frequency device is producing a wave with wavelength 25,000 miles long in the room!

Geoff Kait
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the key for the success of listening

It's so important that the listener takes back his or her domain when it comes to this hobby. Measuring it instead of learning the art of listening has made a joke out of this industry. How can you have an industry about listening when no one is doing it? People who trust what a mic says instead of learning how to use the system and your ears. We've been at this thing much too long to still be playing on a radio shack level. The only way to learn this hobby is to get to the place where (as TM says) you use your "gut feel". I tune halls all the time and sometimes the engineers say where's your stuff? I answer "I'm wearing them".

Remember back in the day when I started showing up at places and the reviewers would talk about me walking around their rooms making noices? The clap test, and the boo test, and lets not forget the hiss and thudding the walls tests? These were funny times for me. Things I did in studios and halls all my life and the audiophile world thought it was something weird or unconventional. lol

my-O-my

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But what you hear depends on

But what you hear depends on the amplitude of the wave doesn't it? So as long as part of a wave is in the room and it's amplitude (movement of air molecules) is greater then zero we could hear it (within our frequency range of hearing of course). I think the real point is not that you can hear the sound but that you need to hear the full amplitude at your listening position to get the correct volume as intended from the recording.

Whilst I'm new to Michael Green's concept of listening to audio, as I have gone down the bass trap/absorption route, I'm intrigued! I'm only a music listener with experience limited to his own room.

Logic tells me that the sound emanating from your speaker, barring limitations of gear etc., is what the music engineer intended me to hear. He presumably decided on the result by listening to monitors in an acoustically treated studio. After this sound comes from the speakers it is of course interfered with by the room and its contents. However I don't understand the connection that Michael made earlier that because a musical instrument, like an acoustic guitar, has a resonating box, so a listening room should be similar.

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musical instruments

Hi Hipper

welcome to the forum

"However I don't understand the connection that Michael made earlier that because a musical instrument, like an acoustic guitar, has a resonating box, so a listening room should be similar."

We listen in rooms, therefore that room is a part of the sound. There is no way to remove the room, and why would we want to, it's a great natural amplifier if put in-tune with the music. And in-tune is all about resonance. When you go to a fine music event of listening, the better the hall sounds and the more it gives, the less the PA (if any) needs to work. Same with a listening room. Think of it as a mini concert hall just for you.

When you think about it, some of the things the audiophile and some engineering worlds try to do is opposite from the rest of the music world. Take a tour of the best open sounding halls on the planet and compare them against the ones that have been over dampened. The music in the dampened halls is dead and lacking natural dynamics, needing that PA system. But the halls that give to the music, these are the ones that give the magic. Same with our listening rooms. Big difference between using a room and fighting against a room.

michael green
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Different Approach to Listening

Thanks Michael.

I've operated on the principle (because until now that is all I've learnt, and it seems logical) that all the information I need is in the recording and all I have to do is get the gear, set it up right, and remove room interference in order to hear the recording as intended at my listening position.

You are saying that in fact the best I can do is to alter the sounds of the recording with my room as it's not possible to remove it from the equation. This means presumably that a recording will sound different in a different room and that is acceptable.

Is that a fair interpretation?

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the room is the system

Hi Hipper

The room is every bit as much of the system as any other part is, in fact it's the biggest part. The room is part of the audio chain and if you make it not able to translate the music it won't, and if you make it apart of the amplification system which it is and make it true to the source the music will come to life. "remove room interference" and "alter the sounds". These are two important phrases and every audiophile no matter how long they have been in this should take a look here. Audiophiles have been taught for years that the room is a source of interference, when they should have been taught that the room is an amplifier needed to allow the sound we hear to form. Without the room there is no hobby. It's also not about altering the sound as in changing it into something it is not (distortion) but more having the room as the ultimate music voicing tool to bring out the music content. Once you get use to using the room you will learn more about this hobby than any magazine or book will ever teach you about audio. This hobby has made a few mistakes and one of them (one of the biggest ones) is trying to remove something that is essential to the listener. The room is the biggest playground in this hobby and is what you are hearing unless you are using headphones. The speaker is only what is making the waves start, it's the room that carries and delivers the waves and forms the pressure we hear. This industry has two areas that are still in it's infancy. One is passing the signal, and the second is delivering it. One major problem this industry needs to work through is in the area signal vs vibration. Up till now they have got it wrong. And as we are talking about here, the room as a part of instead of trying to teach the removal of. In both these areas you will find on TuneLand http://tuneland.techno-zone.net/ that we have figured them out and using them to their fullness.

The industry as a whole will correct itself in time, but the short cut is to free the audio signal and then tune it in, and use the room as your acoustic component.

have fun and visit us if you get a chance

michael green
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Small rooms hurt low bass

In many instances, small rooms hurt the low end because it's more difficult to properly position the speaker in the room and still have room for functional use. Take a 12x15 room, for example. The center of the speaker driver should be about 3'4" from the side wall and 5'4" from the front wall. That would leave the speakers about 5 foot apart and the listening position about 5' away from the speakers.

That would work for a dedicated listening room, but if you wanted to use the room for things other than listening, you're going to have a hard time unless you are prepared to move your chair and speakers around constantly.

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Wow

Wow catch where did you get that?

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The Cardas Method for Speaker Placement

Most people have to compromise from his method for obvious reasons, but boy does it work wonders if you can implement it.

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George

Well I like George alot, and he has always been nice to me. He's a really cool guy and very hip, but this is one area where he and I would probably differ on (maybe not would have to talk to him directly). Mainly because of all the conditions rooms have that dictate their sound, most of them that have nothing to do with number formulas. I've made and have had many clients who have rooms that were almost identical in size and sounded nothing like each other. Formulas may help some people for general ideas but I have also seen them do as much bad as good.

an example

We built rooms identical in our testing labs, and with something as simple as paint type being different the rooms measured and sounded completely different. We did the same with different materials. Same exact sizes but the wall material in the one we would change out. Every time we changed the materials the room's sound took on it's own unique character. Not by a small amount either, totally different sound. These were part of the Nashville, and TuneVilla tests if you ever look them up.

Designing and building rooms and being able to study their reactions to all types of conditions made me throw out the rule books. They make for nice stories but really not much else. Test CD's and formulas and theories I think are all fun parts of the hobby to explore but actual doing sometimes gives a far different picture into what is really going on. If the formulas happen to help people that's great, but when someone replaces listening with a formula that's where a lot of troubles start. I would trust a method of listening much faster than I would put my faith in a formula that was done based on one scenario.

michael green
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Room Treatmeant

I agree with Michael on this one. I don’t think there is a tried and true place to position your speakers or that a formula will work in all cases. It normally takes me months when I switch to a new room to find what I think is the best placement. Here is why, your placement will inevitably be a compromises. To wide and you can have a great soundstage but no center. To close together and you don’t have any separation but very focused center. Add into this the toe in angle and bass response from the boundary interaction and it takes a while to strike the right balance. Also for bass response your seating position is just as important as speaker position so you also need to dial it in. The above may makes it sound difficult but I normally start with an equilateral triangle and adjust from there and you will slowly center in on what you like (actually recently purchased a pair of good headphones that has really helped me make decisions on position as I can use it as somewhat of a reference).
In terms of room treatment (absorption and diffusion), I’m a huge fan and think it offers a number of sonic benefits. With that said, I also agree with Michael that the goal of treatment isn’t to remove the room but to get it to settle into the music. For me I always find small room to have two issues, high frequency reflections and low end room modes. For me the addition of absorption is a way to bring the frequency response and decay times more in line with a neutral room. With that said you do need to be careful, for instance when I first started room treatment I tried foam and while it relaxed the highs it did nothing for the low end so I was left with a strange unbalanced sound. So the point is, if you use absorption you need to try and take into account that it needs to be broadband absorption and you need to be very careful when you target certain frequencies, but I’m under the general belief that most system would benefit from some form of absorption or diffusion.
As far as tuning the room, I think most people have the same goal in mind, just different ways to do it. Of course, it all depends on what you are going for.

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Speaker placement

Actually, and unfortunately, it's an incorrect assumption that one can find the perfect locations for speakers in a given room by moving a little, listening a little. The reason I say this is because that particular method cannot find the ABSOLUTE best locations, only what we call local maximum locations. The local maximum locations might be good, they might be very good. But they aren't as good as the absolute maximums. The absolute maximum locations CAN be found for any room very easily with the XLO test CD on the track for speaker set up. This is actually quite a shocking and fascinating development since the speaker set up track allows one to find the ABSOLUTE BEST locations for BOTH speakers - independently of speaker type, room size, room treatments, room tuning, whatever, or listener position. Now, having said all of this, one can improve upon e sound that results by adding more room treatments, with the following caveat: you will have to redo the XLO Test CD speaker set up track every time you change or add room treatments. But that might be too obvious.

Attempting to determine the absolute best speaker locations by ear ALONE is analogous to trying to solve two simultaneous equations in 3 or 4 unknowns. In, fact, if I can be so bold, it's mathematically impossible. I am not against LISTENING, as I am confident some will claim, but I am FOR the XLO method in CONJUCTION with listening, which will allow you to find the IDEAL locations of both speakers, each speaker position within 1/4 inch. And you will most likely find that the IDEAL distance between speakers - the one that provides the absolute best soundstage and best frequency response, etc. - that you obtain using my method is probably MUCH LESS than you assumed. And that toe in is neither required or particularly good for the sound in most cases.

Cheers,

Geoff Kait
Machina Dynamica

Catch22
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The Cardas method doesn't always work

This is true and you'll get no argument from me on there being no "one size fits all" method to speaker placement. However, bad speaker placement requires more effort to overcome with room treatments, that in many cases end up being just as problematic as properly positioning speakers...and they aren't free. Speaker placement is a freebie if you can employ it.

Even considering George and his fascination with Fibonacci, other acceptable methods of addressing room nodes when placing speakers aren't terribly different in practicality as far as not having them encroach well into the room and away from side walls that leave the listener in a near field listening situation with small rooms.

For example, using the Real Trap method, the only difference would be a couple of inches. Using the "thirds" method would move the speakers only slightly closer to the front and side walls by a few inches and leave 5' between them. My point being that we are only splitting hairs from a pracatical standpoint insofar as the usability of the room is concerned and by not using basic math to position the speakers, it will REQUIRE that room treatments be employed to correct for discounting or ignoring the math.

I agree with Geoff on the use of test tones and a spl meter. They are indispensible tools for setting up a listening room...with the added benefit of being a bit revealing of your own bias on what you enjoy hearing. And, they're fun to play around with. lol

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Correct speaker for room

Any discussion of speaker and rooms also needs to account for the correct speaker for a room. Large or floor standing speakers in a small room vs monitor or monitor/sub combination. Additionally other factors like ported/sealed designs, inert or resonant cabinet materials affects things also.

The floor standers, in a furnished room, will most likely require more effort to correctly pressurize the room and allow it to fully and equally develop the acoustics.

Catch22
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Absolutely

Speaker choice for a given room is a big deal and people wonder why their system doesn't sound as good as when they heard it at the audio shop.

I've found that my system sounds its best at a certain listening level where the room is really coming into play. Unfortunately, not all recordings are presented with the same signal level and I have to get my ass up to adjust my amps.

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I know what you mean by that

I know what you mean by that perfect volume setting where the room is nicely pressurized and music is presented effortlessly.

I lucked out when I moved to my current simpler tuned setup using receiver that has a remote after years without one. Funny thing is, I don't have to adjust the volume as much as I did in the past. A little adjustment for signal but not nearly as much as I had to especially for compensating for flat or dead recordings.

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nah

Audiophiles make this stuff much harder than it is. Take a look at this, I set it up just for you guys. http://tuneland.techno-zone.net/t245-setup-basics-for-stereophile#4386 . I think maybe a lot of you guys (by the way your talking) have never done the RT basics before. There's no reason to fight your room or make speaker placement harder than it is.

michael green
MGA/RoomTune

Catch22
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Here's a good read on speaker placement and room acoustics

Robert Harley moderating a round table discussion with acoustic treatment chaps. Even they can't agree on the right approach. lol

Anyway, here's Robert Harley's final paragraph.

I’d like to conclude by adding my own comment about the single most effective technique for improving the sound of your room: loudspeaker placement. Through loudspeaker placement you can control the amount of bass, overall tonal balance, image specificity, and soundstage width. Speaker placement has its limitations, and the sound will still be greatly influenced by the room, but I suspect that most readers’ systems could be improved by better speaker placement. RH

http://www.tubetrap.com/bass_traps_articles/tas-RoundTable.pdf

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what do you see? I must be a snob lol

You know, when I read articles I wonder what people are thinking. First of all who's writing the article, and second their general knowledge, and third what they say based on that knowledge. For example, it's hard for me to take someones advice, or seriously if they are not in the know about the whole picture (the whole audio chain). If I doubt them in their listening practice I can't depend on them for the other parts of "audio".

comparing the two

When I look at the video that was put on the other thread featuring the musician, it was easy to believe because it was all about music. I felt there was much there to learn about the sensitivites of sound pressure. The flip side to this is reading this article. I didn't feel like these guys were talking about music and it's sensitivities. To me it sounded like another audiophile math class, and hopeful theory pushing.

We hear sound pressure, but was that phrase mentioned once? Not once! I think SPL was only mentioned once. Reflection was mentioned all over the place but rooms don't make most of their sounds by single wave reflections do they? Do you guys sit in your chairs and hear reflections? I hear pressure zones. My ears are not hearing a bunch of 20-20hz pingings, do yours? While sitting at your chair listening tonight let me know what frequencies you heard pinging off the wall. I'd like to know. I'd like for someone to demo that for me. Someone to get out their 300hz laser and show me the wave reflecting around the room. Someone please demo to me a first reflection. And then that same person demo to me 20,000 of them. I'd like to know how that works cause I've never been able to do it and I've been an acoustician for 30 years now. I've seen people interupt the laminar flow along the wall all day and night long, and change the shape of pressure movements toward me but not a first reflection, and not a second or third either in the room the size of a listening room. Maybe one of these gents would come over here to my place and straighten me out.

Musical note was also brought up one time. Frequencies again were brought up all over the place, but not musical notes. Did I see the words harmonic structures any where? Maybe I was getting bored but I saw very little here about music. What stuck out was that rooms reflect, which I don't hear happening, and frequencies, but when my music plays I don't hear one frequency, not one. I hear notes which are far more involved than a frequency.

I also heard the room in the negative a lot instead of a positive. This is disturbing to me. I see rooms as positives and have worked on them from the tiny to the very biggest and when I hear guys talking about them as something to remove I don't see that person as an acoustical expert at all, but more one who has failed at turning them into instruments.

I also heard the acoustician say "equipment doesn't break in". Right off the bat he gets a "F" for system knowledge.

Then in the middle of all this as Catch says, they can't agree on their spins.

So here we have audio experts that can't agree. Are they really experts? I see someone demostrating as a truth, I see someone making variable predictable changes as a technician who presents his version of a truth, I see someone writing as someone with a keyboard, I see someone making products as a salesman, I see someone talking about math as a mathematician, but what I didn't see here was anyone giving people a method of listening. Something that they will tell you but also walk through your room with you and you hear for yourselves so you can make a decision. I decision of yes here's how this is working and here's how I can use this.

These guys to me sounded like guys coming to a home to fix something when nothing is broken.

michael green, maybe I'm a snob but it's not that difficult
MGA/RoomTune

audiophile2000
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A Bit Harsh

Not to be controversial here but the truth of room acoustics is it can in theory be perfectly simulated. That is, the room and the sounds interaction is purely mathematical at its core. So before everyone jumps on me for that statement, I said in theory. The truth is, any model, no matter how complex is a simplification of reality that helps us understand to predict what is going to happen. So does that mean we completely discount models, no they are representations of reality that can help us understand what is going on. Now you can say models only get us part of the way, and that's true since reality is much more complicated than any audio models I have ever seen.

On to frequency, the truth is all music is, is a bunch of frequencies. Its nothing else at its core so to say that you don't hear frequency, that's exactly what you hear. In fact frequency and decay times are what harmonic structures are and represent what sound is and how an instrument sounds. I agree we can take math to far sometimes but none the less, it is still the fundamental truth. To give you an example, we still don't completely understand gravity at a fundamental level but you don't find anyone saying gravity doesn't exist. Maybe a but harsh but there really isn't magic here.

To the point of first reflections, you are right that there are an infinite number of reflections in a room and can always debate weather it makes sense treat it, but that doesn't change the fact that it is there (I agree its a bit complicated when you take into account directionality of sound, but again these are some simplifying assumptions. Its good to see people go different directions and explore options but not all of acoustic theory that exist today is wrong. Personally, I have always seen the center focus us with treating first reflection.

Also will touch on a point the article mentioned and I think its more fundamental than the above. We all have different ways to listen and different paths. I think the thing to keep in mind is some may go for wide soundstage, some for ultra focused centers, some for a relaxed / lively sound others for recording studio sound. Whatever your flavor there is nothing wrong with that.

Personally I have found that absorption and diffusion is the industry standard in the recording world. So while there may in fact be better or different methods of tuning. If you want the sound of a mastering room / a studio, its good to base your room design on that employed by a mastering room (weather right or wrong. Of course there is not right and wrong here, really just preferences and goals.

michael green
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Hi 2000

I hope you understand it's my job to be more critical than the norm. I have to explore theories and uncover their truth or not so truth. In my job math comes after the fact not before. For example, I have to deal with concrete rooms as well as flexible, and the test CDs or any other tests in these two types or 4% humidity vs 80% or elevations, or furniture and furniture types, don't even come close when using the same test (standard) for these room differences. So in saying that it would be wrong for me to say useful. The only thing I could say would be fun to play with, but not accurate.

On the frequency, a note is so much more complex than a group of frequencies that I would have to disagree on this one. Frequencies are limited as compared to notes. For example, play a frequency on your speaker, now try to play that frequency on a musical instrument, completely different sounding. Set 5 instruments up and try the same. Now go back and play that frequency on two different speakers, they again sound different. It's safer to again use a frequency as a meassuring tool for those who wish to view their equipment on paper, but not so good to think of a frequency as real, or you will assume that all objects of sound will perform the same through different mechanical conduits and the truth is they don't. Easy to test this btw.

On reflections, It's funny to me how the audiophile world tries to put things in neat boxes instead of enjoying the uniqueness of their particular setting. I guess this type of thing helps those who have hard times picturing what a room is doing. I'm going to try to help here http://tuneland.techno-zone.net/t245-setup-basics-for-stereophile .

I think that from what people come to me saying is they do indeed have a taste, just don't know how to get there often enough.

On the A and D thing, if someone has painted a standard, they haven't been to many studios. It's important to keep in mind that the studio engineer is just as green as the audiophile when it comes to listening. They have foam, traps, diffusion, tunes and all kinds of other things and none of these setups are understood any more than you in your own room. To be honest I have known more advanced home listeners to be better at acoustics than the studio engineers. It would be a mistake to think that the tools they use and how they use them has anything to do with your listening in your home. Now I say this as someone who has many of the big name studios as clients. If you came on a studio tour with me, the first thing you would say is how different they sound from each other. There is no standard and the products they use are usually what a sales rep gives them. If your picturing them tweaking you would be pretty far away from reality as far as most studios go.

Go to their 4 rooms and hear for yourself. Live, control, master and playback and then tell us what you hear. I've not been to any studio other than my own built to reference where any of the 4 rooms sounded the same. It would be great if this were true but this is not the practice.

no jumping on you to be done, just some real life experience

michael green
MGA/RoomTune

michael green
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The Vegas Towers

Hi Audiophile2000

I also wanted to say that as you mentioned a while back that you lived in towers. If you look up the show report on TuneLand 2005 you will see the reports based on my suite in The Vegas Towers. I didn't want you to think that I have had no experience in highrise tuning. Also my penthouses in both Nashville and Manhattan were obviously high rises. I try really hard to cover all the basis.

I also want to tell you I really appreciate your politeness on the forum here.

michael green
MGA/RoomTune

geoffkait
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Recording studios and room treatment

Audiophile2000 wrote,

"Personally I have found that absorption and diffusion is the industry standard in the recording world. So while there may in fact be better or different methods of tuning. If you want the sound of a mastering room / a studio, its good to base your room design on that employed by a mastering room (weather right or wrong. Of course there is not right and wrong here, really just preferences and goals."

I have no problem with that except I have a bad feeling that many recording studios use the "industry standard" SONEX, one of the worst things ever perpetrated on gullible and unsuspecting audiophiles. Even in small amounts Sonex does something peculiar to the sound, making it sound fuzzy, wooly, phasey or all of the above.

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Geoff Kait
Machina Dynamica

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