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It's more dry in a way, like the majority of the pressure waves are less noticeable.

It appears as you are making good progress.

A peculiarity of bass traps is they can actually hurt the sound when placed in the corner of the room. All depends on the actual location of the energy peak you're attempting to absorb. The peaks don't necessarily set up in the corner - shocking, I know. Every room is different and every speaker has it's own radiation pattern. The optimum location for each trap could be a foot or two away from the corner. Hard to say for sure without a sound pressure level meter.

Cheerio

Every small untreated room exhibits excess bass. Trihedral corner reflections are always the strongest. The corner is the best placement, either on the floor or toward the ceiling.

You are never going to hurt the sound by absorbing some of the excess bass.

It is true however that if there is a specific peak you want to attack, you need to make adjustments for this specific frequency - but this isn't going to be his issue.

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Every small untreated room exhibits excess bass. Trihedral corner reflections are always the strongest. The corner is the best placement, either on the floor or toward the ceiling.

You are never going to hurt the sound by absorbing some of the excess bass.

It is true however that if there is a specific peak you want to attack, you need to make adjustments for this specific frequency - but this isn't going to be his issue.

Maybe time to pull out the old Radio Shack SPL meter and see where those squirrely low frequency standing waves really are.

Cheers

Knock yourself out.

Remember to take lots of measurements in many positions, and at different frequencies.

Or rely on the many published works on acoustics already out there.

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Knock yourself out.

Remember to take lots of measurements in many positions, and at different frequencies.

Or rely on the many published works on acoustics already out there.

Thanks for all the tips anyway, but I've been doing this measuring of room acoustics thing for years. It's like, you know, part of my J-O-B description.

I have a pronounced tendency not to rely on published works on acoustics, if you want to know the truth. Is that wrong?

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The problem isn't as much a peak as it is an overshoot of bass, best heard close to the back wall, and in all 4 corners. The closer to the floor, the more excess bass. I don't really know what to call it, but that is what I am working on.

Actually I have placed some old speakers in the 2 corners opposite from the speakers, in order to help the "bass traps", and it seems to work, but only takes away some of the excess bass.

You rock, good buddy! Now, we've got to work on what in the heck to do about the excess higher frequencies in the upper corners of the room, at the ceiling.

Cheerio

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Thanks for all the tips anyway, but I've been doing this measuring of room acoustics thing for years.

Excellent.

Then tell us specifically what you have found to be the case as it relates to the behavior of low frequency sound waves (less than 150 hz or so) in the typical small listening room.

I have not seen anyone dispute that bass builds in the boundaries, particularly the corners - but if you have different specific knowledge please share.

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Thanks for all the tips anyway, but I've been doing this measuring of room acoustics thing for years.

Excellent.

Then tell us specifically what you have found to be the case as it relates to the behavior of low frequency sound waves (less than 150 hz or so) in the typical small listening room.

I have not seen anyone dispute that bass builds in the boundaries, particularly the corners - but if you have different specific knowledge please share.

I'm pretty sure I already answered your question. But to be a little more specific, the low frequency standing waves and reflected waves can located in the 3-D space of the room, including boundaries, with an SPL meter and test tone of the frequency under investigation.

Cheers

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But to be a little more specific, the low frequency standing waves and reflected waves can located in the 3-D space of the room, including boundaries, with an SPL meter and test tone of the frequency under investigation.

Of course, standing waves in many places throughout the room depending on its dimensions and frequency. All of this can be mathematically predicted, much easier than pulling out a mic and plotting software.

But this isn't the issue.

I pointed out "Every small untreated room exhibits excess bass. Trihedral corner reflections are always the strongest." "You are never going to hurt the sound by absorbing some of the excess bass."

You suggested pulling out an SPL meter "and see where those squirrely low frequency standing waves really are."

Yes, an individual frequency will have a standing wave somewhere in the room with the number of such locations increasing as the wavelength decreases.

But on point:

Do you dispute that bass builds in the boundaries, particularly the corners?

Do you dispute that bass builds most strongly in trihedral corners?

Do you dispute that a broadband bass absorber is most effective in such corners?

What Keld did was exactly correct. He describes broadband excess bass. By absorbing the bass where it is strongest he effectively decreases standing waves elsewhere in the room - always a good thing.

Of course, if he possess a completely unique room which exhibits standing waves at only one frequency he may simply want to move his listening chair a tad.

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Do you dispute that bass builds in the boundaries, particularly the corners?

Do you dispute that bass builds most strongly in trihedral corners?

Do you dispute that a broadband bass absorber is most effective in such corners?

Yes, I dispute all of the points above as being too simplistic or just plain incorrect.

Without an SPL meter and good selection of test tones, one will only get an approximation.

But probably good enough for Government work.

Cheers

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Right behind my listening chair (I have moved it a bit forward) there's a clearly audible collision of bass waves. Anybody in their right mind can hear that.

Eggs-actly! The location of standing waves - of any frequency - in the room is not predictable, and certainly not relegated to room corners, so in order to locate them all, a procedure is required that will find ALL of them and their exact locations.

I am not limiting my comments to bass frequencies, as all frequencies are important and should be dealt with.

When you assume something, you make an ass out of me and Uma Thurman. - old audiophile expression

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I believe it's the other way round: Work on taming the corner build-up, and you'll eventually get rid of the standing waves colliding like they do right behind my listening position.

Hope springs eternal in the human breast.

An ordinary man has no means of deliverance.

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Not a bad place to start

You will have more in the end if you have more when you start out. - Law of Optimization

Thimk ahead.

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Do you dispute that bass builds in the boundaries, particularly the corners?

Do you dispute that bass builds most strongly in trihedral corners?

Do you dispute that a broadband bass absorber is most effective in such corners?

Yes, I dispute all of the points above as being too simplistic or just plain incorrect.

One doesn't treat standing waves, one eliminates their cause (interference reflections). The best way to accomplish this is to absorb the bass frequencies where they congregate; that is trihedral corners, with two surface corners the next best.

(Think wiping out the ant nest instead of squishing each individual ant on the floor where it happens to appear.)

Once again, what is incorrect with this approach?

What is too simplistic?

What is the specific better alternative?

We can handle the complex. Explain precisely what Keld should do and why this will work. Go for it! Share your knowledge!

(Keld, I assume you have already tried various seating positions and speaker placement to minimize your existing acoustic issues. If not, this is the place to start.)

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Do you dispute that bass builds in the boundaries, particularly the corners?

Do you dispute that bass builds most strongly in trihedral corners?

Do you dispute that a broadband bass absorber is most effective in such corners?

Yes, I dispute all of the points above as being too simplistic or just plain incorrect.

One doesn't treat standing waves, one eliminates their cause (interference reflections). The best way to accomplish this is to absorb the bass frequencies where they congregate; that is trihedral corners, with two surface corners the next best.

(Think wiping out the ant nest instead of squishing each individual ant on the floor where it happens to appear.)

Once again, what is incorrect with this approach?

What is too simplistic?

What is the specific better alternative?

We can handle the complex. Explain precisely what Keld should do and why this will work. Go for it! Share your knowledge!

(Keld, I assume you have already tried various seating positions and speaker placement to minimize your existing acoustic issues. If not, this is the place to start.)

Geez, and I thought Scott was argumentative.

What is it about my explanation that you don't understand? I'm not so sure "you" can "handle the complex," as you put it. And I'm not about to try and change the mind of anyone who has already made it up.

I'm not trying to set the world on fire, just trying to start a flame in a few hearts.

Interestingly, with the rolled-up foam method you have actually created a variable density device, with the center being more compacted than at outer edges.

That can actually have different sonic effect than, say, a roll of insulation that is not compressed in the center.

Keld, you could also experiment with rolling your foam more or less tightly, perhaps even using a shorter length of foam and trying to make a non-compressed bass trap.

Sorry to interupt the pissing match!

Carry on.

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Interestingly, with the rolled-up foam method you have actually created a variable density device, with the center being more compacted than at outer edges.

That can actually have different sonic effect than, say, a roll of insulation that is not compressed in the center.

Keld, you could also experiment with rolling your foam more or less tightly, perhaps even using a shorter length of foam and trying to make a non-compressed bass trap.

Sorry to interupt the pissing match!

Carry on.

What are you going on about, now? "Variable density device."

"Oh yes, I'm the great pretender..."

You'll figure it out.

Or are you just upset your bitch-fest was interrupted?

You give yourself too much credit, you're a lousy pretender.

I imagine your record collection is converting a lot of bass energy to heat, eh?

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Seriously? I don't think so.

Would I kid you? I don't think so.

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I don't know if you would, but you may be right now that I think about it.

It'll be our little secret.

I wasn't going to bring this up, but are the three large acoustic resonators you have on the wall behind the speakers by design?

I like the Fedora Tweak on each of your speakers.

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You mean the CD shelves?

Actually, I was referring to the CDs themselves, if you catch my drift.

yes, the acoustics work from those hacks Everest, Blackstock, Toole, Geddes, John Sayers, Blumlein, and others..all part of a conspiracy whose goal is to rob home listeners of their *sound*

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yes, the acoustics work from those hacks Everest, Blackstock, Toole, Geddes, John Sayers, Blumlein, and others..all part of a conspiracy whose goal is to rob home listeners of their *sound*

No smiley face?

You've been through all of F. Scott Fitzgerald's books
You're very well read, it's well known
But something is happening here and you don't know what it is
do you, Mr. Jones?

~ Cheerio

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I like the Fedora Tweak on each of your speakers.

Hehe, from a recommendation from Buddha there's 13 lbs of metal under each "fedora". Just so you're careful when putting one of them on your head

Did it occur to you there's the distinct possibility you're following the wrong sheep?

DIY ASSHATS???

Wow Geoff!

Maybe you could try begging for customers next?

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DIY ASSHATS???

Wow Geoff!

Maybe you could try begging for customers next?

Geoffie has been working through alot of anger issues lately.

He even forget to ask the IQ of the clock on Keld's wall above the turntable or the other room improvement devices that are more up Geoff's tube of joy.

Looks like Keld has a....

Talented Timepiece

Perspicacious Pyrometer

Holistic Hygrometer

In Geoffie's world, he just missed several thousand dollars in revenue that seems to have gone into Ikea's pocket. Of couse he's pissed off!

Even more telling, Keld saying he heard a difference makes no difference to Geoffie, either. Completely beside the point. Just makes him wanna shake his tiny fist in rage!

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DIY ASSHATS???

Wow Geoff!

Maybe you could try begging for customers next?

Geoffie has been working through alot of anger issues lately.

He even forget to ask the IQ of the clock on Keld's wall above the turntable or the other room improvement devices that are more up Geoff's tube of joy.

Looks like Keld has a....

Talented Timepiece

Perspicacious Pyrometer

Holistic Hygrometer

In Geoffie's world, he just missed several thousand dollars in revenue that seems to have gone into Ikea's pocket. Of couse he's pissed off!

Even more telling, Keld saying he heard a difference makes no difference to Geoffie, either. Completely beside the point. Just makes him wanna shake his tiny fist in rage!

Boy, Geoffie, we can't even have a discussion with Keld about his room tweaks without you turning into a bitch.

I think you should get yourself a Hi Fi and cheer up.

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Boy, Geoffie, we can't even have a discussion with Keld about his room tweaks without you turning into a bitch.

I think you should get yourself a Hi Fi and cheer up.

Geez, you'd think your Machina Dynamica hard on would go down eventually. You always said it was psychological.

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Boy, Geoffie, we can't even have a discussion with Keld about his room tweaks without you turning into a bitch.

I think you should get yourself a Hi Fi and cheer up.

Geez, you'd think your Machina Dynamica hard on would go down eventually. You always said it was psychological.

Psychological, at this point, as in you have some psychological issues.

You get pretty riled up with Keld talking about damping, don't you?

Maybe you can go try to wreck a discussion in the classical music forum....you can opine about the lack of coverage you've been getting there.

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Boy, Geoffie, we can't even have a discussion with Keld about his room tweaks without you turning into a bitch.

I think you should get yourself a Hi Fi and cheer up.

Geez, you'd think your Machina Dynamica hard on would go down eventually. You always said it was psychological.

Psychological, at this point, as in you have some psychological issues.

You get pretty riled up with Keld talking about damping, don't you?

Maybe you can go try to wreck a discussion in the classical music forum....you can opine about the lack of coverage you've been getting there.

Can I prescribe a little Vivaldi and a nice cold shower for you?

at least he is in the performance art career sector rather than aerospace design.

Clever Little Vertical Stabilizer?

Nimbus Aileron?

the new Intelligent Orbiter?

at least in performance art his work is not a liability.

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at least he is in the performance art career sector rather than aerospace design.

Clever Little Vertical Stabilizer?

Nimbus Aileron?

the new Intelligent Orbiter?

at least in performance art his work is not a liability.

I'll handle the jokes around here, you sick little monkey.

Keld, You are a charming and generous person. An asset to the forum. When joking and insults are directed your way, you usually disarm your antagonist by taking the high road instead of freaking out. What a guy!

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Keld, You are a charming and generous person. An asset to the forum. When joking and insults are directed your way, you usually disarm your antagonist by taking the high road instead of freaking out. What a guy!

So, all of a sudden I'm the bad guy for trying to get the level of the discussion a little higher than Novice? Well, that's just great!

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Keld, You are a charming and generous person. An asset to the forum. When joking and insults are directed your way, you usually disarm your antagonist by taking the high road instead of freaking out. What a guy!

So, all of a sudden I'm the bad guy for trying to get the level of the discussion a little higher than Novice? Well, that's just great!

You and KBK have to grab us by the scruff of our novice necks and drag us to the higher truth. Even if it involves pictures of goats. It's a dirty job...