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Elk
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Re: DBT testing


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Ethan, if a note's timbre changes, then the spectrum of FR will change, that's easy to understand; however, if a given note's fundamental and range of harmonics stay the same, maintaining the same basic timbre, but the individual harmonics are easier to distinguish, then how will that change FR??? I'm going to need some sort of very refined spectrum analysis to see a difference, I suspect.


This is a great question.

I think you are right, that the measurement will need to be refined. I think this is well within our ability to measure however.

I, too, have heard cables with greater clarity - as well as cables that sound dreadful. I am with Ethan in believing that these differences should be measurable.

Ethan's suggestion that we compare waveforms of the exact same piece of music with just a difference of cables is excellent. This is as detailed as we can get as the waveform tracks both frequency and time. If the changes are in teh timing we will see a difference. If they are in frequency we will see a difference.

We do need to record electronic output and not speakers however, comb filtering and all.

SAS Audio
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Re: DBT testing


Quote:
Ethan, if a note's timbre changes, then the spectrum of FR will change, that's easy to understand; however, if a given note's fundemental and range of harmonics stay the same, maintaining the same basic timbre, but the individual harmonics are easier to distinguish, then how will that change FR??? I'm going to need some sort of very refined spectrum analysis to see a difference, I suspect.

Hi DC. Your question is a good question. As an example, the DA (dielectric absorption) and ESR (equivalent series resistance) of different types of capacitors affect the clarity of the harmonics you are hearing. Electrolytic caps are among the worst, Polyprops are among the best. As you know, DA and DF do not change the frequency, just the clarity because the charge and discharge are not instantaneous, but "smeared" over time.

Wire is another example, depending upon the material, purity, and size to current, terminations etc.


Quote:
I think that you're over simplifying by saying that it'll show up in a FR comparison.

You are right Dave. It won't show up by just measuring the frequency response, unless the response is wildly off on either the bottom end, top, or both.

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Re: DBT testing

It was the ONLY company to respond...and that was when? I read that decades ago.

CECE
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Re: DBT testing

Nothing to dance about, like he said, otehr's in his group heard nothing, it is sugar pill effect, and he got to keep free cables, why not say they are good. Who else sent him any cables, no one. I've used non cables and it sounded and beat stuff with fancy cables, and I knew the cables where cheap, and it still sounded better than the ones with facny pants wires. Reverse Pacebo effect, like Bizzaro world? Everything is oppasite, yet works better. Not bizzaro world, DUP world, you may say it's wrong, but it does it all better. Accept it, get over it, it's true. It's not a comb effect causing problems, it's HAIR BRUSH effect making it better.

dcstep
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Re: DBT testing

Yes Elk, I too think that it can be measured, but not necessarily easily, or with basic equipment. Ethan seems to say that FR reveals all, but I don't think that's true.

Dave

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Re: DBT testing

SAS, have you ever seen anyone measure and display what I'm referring to?

Dave

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Re: DBT testing


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and that was when?

That was from decades ago. So was the "As We See It" article that started this thread off. And thank you for pointing out what I consider one of the most interesting aspects of this subject

Elk
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Re: DBT testing


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Yes Elk, I too think that it can be measured, but not necessarily easily, or with basic equipment. Ethan seems to say that FR reveals all, but I don't think that's true.


I think timing is an issue. Thus, I think measuring and comparing the waveform of music is a pretty good test.

After all the waveform is what our equipment produces and what we listen to.

As an example, there were differences in the two waveforms posted of two different AC cords some time back. I could also hear the differences.

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Re: DBT testing


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I disagree about instantaneous testing. In one drop increments, I may not be able to tell Mouton from Two Buck Chuck, but with a proper glass, it would be obvious.


I don't know what you're responding to, but I never suggested that music fragments should be one second or less. When I do A/B tests I usually load both files into Sound Forge, put the "now time" cursor at the exact same place in both files, then alternately click the Play buttons for each file. I typically play one to four bars of music. But sometimes only a few seconds.

--Ethan

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Re: DBT testing


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Nothing to dance about, like he said, otehr's in his group heard nothing, it is sugar pill effect, and he got to keep free cables, why not say they are good. Who else sent him any cables, no one. I've used non cables and it sounded and beat stuff with fancy cables, and I knew the cables where cheap, and it still sounded better than the ones with facny pants wires. Reverse Pacebo effect, like Bizzaro world? Everything is oppasite, yet works better. Not bizzaro world, DUP world, you may say it's wrong, but it does it all better. Accept it, get over it, it's true. It's not a comb effect causing problems, it's HAIR BRUSH effect making it better.

So now you admit there is a sonic difference between cables. Hmmmm.

dcstep
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Re: DBT testing


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We do need to record electronic output and not speakers however, comb filtering and all.

Unfortunately, when testing speaker cable you'll not get the whole picture unless you include the speakers' load and interaction and the resulting impact on speaker output. The EMI is a very big factor in what we hear from our speakers, so comparing input to output won't be so clean and neat as when we just measure the wire.

Dave

Elk
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Re: DBT testing

You are absolutely correct when it comes to speaker cable - you need to test it with a representative load.

ethanwiner
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Re: DBT testing

Exactly, so you record the amp with the speakers connected.

--Ethan

CECE
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Re: DBT testing

No, the difference is the price of reality based products and nonsense. I admit nothing, you are reading into something that ain't there. the biggest change I see in cables, and wires is when they are either connected or not.

CECE
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Re: DBT testing

Elk, ain't you a representative LOAD?

SAS Audio
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Re: DBT testing


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No, the difference is the price of reality based products and nonsense. I admit nothing, you are reading into something that ain't there. the biggest change I see in cables, and wires is when they are either connected or not.

But you have not tested anything. You have not disagreed with that. In fact, you have done no research on which to make any subtantial claims.

CECE
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Re: DBT testing

Decades and decades of experience. I've used lotsa stuff, lotsa stuff. One AC line switch works just like the other, get the specs correct and it all works well. How come the magic wire changes things but no one ever speaks about the AC SWITCH that is next in teh ckt, if the magic wires have sound, why not the components AC line switch? Probably cus they can't readily sell you switches that users can easily replace, thus proves it's all BS, the scammers only sell you stupid concepts for gullible fools. Now go audition some better sounding AC line switches in your stuff. since fuses sound different, notice they are easily changed out, so of course marketeer scammers found another useless thing to sell and create a business...how dopey do you gotta be to be able to "hear" all this nonsense? I'll put my 14ga heavy duty line cord, with no magic titles against anything from any other company, the plain 14ga will win every time, as long as it's hooked to......the correct amplifiers and stuff, like.....AVA. Research done, case closed O.J. GUILTY

SAS Audio
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Re: DBT testing


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Decades and decades of experience. I've used lotsa stuff, lotsa stuff. One AC line switch works just like the other, get the specs correct and it all works well. How come the magic wire changes things but no one ever speaks about the AC SWITCH that is next in teh ckt, if the magic wires have sound, why not the components AC line switch? Probably cus they can't readily sell you switches that users can easily replace, thus proves it's all BS, the scammers only sell you stupid concepts for gullible fools. Now go audition some better sounding AC line switches in your stuff. since fuses sound different, notice they are easily changed out, so of course marketeer scammers found another useless thing to sell and create a business...how dopey do you gotta be to be able to "hear" all this nonsense? I'll put my 14ga heavy duty line cord, with no magic titles against anything from any other company, the plain 14ga will win every time, as long as it's hooked to......the correct amplifiers and stuff, like.....AVA. Research done, case closed O.J. GUILTY

Excuses, excuses. Again, no actual testing performed.

Lots of companies use and advertise high quality silver switches. Do some research instead of fabricating information.


Quote:
the plain 14ga will win every time, as long as it's hooked to......the correct amplifiers and stuff, like.....AVA.

So plain 14 ga will win every time, so cables do matter. And advertising AVA again.

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Re: DBT testing


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if the magic wires have sound, why not the components AC line switch?


Great idea! Buy a bunch of 49 cent switches, paint them a cool color, then sell them as "audiophile grade" for $99 each. Since it's tough to replace a switch in an amp or CD player, just put the switch inline with a power cord and sell both for $199.99. Claim the extra switch adds clarity, restores full bass, lifts a veil, etc.

See you in a few hours my friend.

--Ethan

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Re: DBT testing

Of course there are all kinds of switches and types of contacts etc. too bad none are relegated to anything but a certain enviroment, to eliminate corrosion in harsh areas, like mfg, arc pitting etc when switching high currents, it's all spec'd out documented, BUT like magic wires, none of teh switches made by legit mfgs claim that it SOUNDS better, it's spec'd for an electrical function, ratings for use, number of make breaks etc. It's all the logical basic electrical design, now you are gonna tell me a silver contact switch sounds different than one that has gold contacts? Of course pittled arc damaged contacts will offer more resistance to a ckt, but that's why ya spec the correct device for the ckt, ya also don't put in 50A rated switch on a 1A fused pre amp or Cd player!!! Neither with an AC cord of like 6ga for a 40W CD palyer!!! Man o' man... Ya also don't put teh cheapest crap that is gonna fail after 500 cycles either....But the "subte" differences claimed to be heard, based on changing a connector or length of wire is nonsense. And I'm sure you can hear how the magic Tara "labs" mislabled wires with the claim of vacuum, sounds better than a Parts Express RCA from STELLAR "labs".....I'm sure both are real LABS!!! Repalcing a devective wire with anything that is working is of course gonna change something, mayb that's what everyone has a bunch of devective corroded broken connectors and frayed wires, so anything they put in it's place is gonna do something of an improvement. Do you also think a ceramic magic fuse versus a glass fuse SOUNDS different? Cus' that ain't what the mfg's make those for, they are arc suppresion mostly for when teh fuse does pop under certain high curren tfaults...the is no sound in a fuse eitehr, the only sound is you paid how much for a glass fuse?!! $38.00 you must be a meathead!!! That sound. So much BS, so little time....now go check your COCHLEA.....

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Re: DBT testing


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Repalcing a devective wire with anything that is working is of course gonna change something, mayb that's what everyone has a bunch of devective corroded broken connectors and frayed wires


Good point. Someone once pointed out to me that RCA connections can oxidize over time. So when you replace one competent wire with another the sound might improve, but only because you exercised the connections. Not because the replacement wire is better. You can get the same "improvement" by simply unplugging and re-seating the same wires.

--Ethan

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Re: DBT testing

Still, after all is said and claimed...different wire sounds different.

SAS Audio
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Re: DBT testing

Hey dup,


Quote:
BUT like magic wires, none of teh switches made by legit mfgs claim that it SOUNDS better,

You just posted wires do sound different. So why the backstep? And yes, manufacturers do claim switches make a difference in the sound.

Have you or Ethan performed even one test?? Neither has ever mention so. So how can you two be taken seriously??

Elk
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Re: DBT testing


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So how can you be taken seriously??


He takes himself seriously.

The rest of us, not so much.

SAS Audio
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Re: DBT testing


Quote:

Quote:
So how can you be taken seriously??


He takes himself seriously.

The rest of us, not so much.

Ain't that the truth. I just hope newbies recognize this right away.

absolutepitch
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Re: DBT testing

Ethan and JIMV,

I've experienced what you both reported. Contacts do oxide over time and working the connection improves the sound. However, cables do sound different too. This is observable by going back an forth between two cables for example. The connections get worked each time. Assuming that the "worked" connections are then the same, the back and forth comparison is due mainly, perhaps overwhelmingly, to the cable i.e. its interaction with the source and load.

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Re: DBT testing


Quote:
Ethan, if a note's timbre changes, then the spectrum of FR will change, that's easy to understand; however, if a given note's fundemental and range of harmonics stay the same, maintaining the same basic timbre, but the individual harmonics are easier to distinguish, then how will that change FR??? I'm going to need some sort of very refined spectrum analysis to see a difference, I suspect.

...

dcstep,

If I recall correctly, both you and Ethan are musically trained. I too, but have been formally schooled in various sciences and engineering fields.

What I hear after circuit modifications on my own gear is that the instruments are better individualized apart from one another instead of having one instrument's sound interfere with another. Spatial localization of each instrument seems to be more stable than before. The result of this is I hear more nuances of the performance getting closer to the music getting more enjoyment from the experience.

At first I heard some difference, but couldn't quite put my finger on what the difference was. This is a noticable effect and not subtle, once I figured out what had changed.

My first thought is that intermodulation distortion may have been reduced, but the electronics already have very low IM distortion specs, and frequency response is very flat in the pre and power amp, and the distortion specs are very low. So I'm still at a loss for a satisfactory explanation.

My hunch is that the 'something' related to the signals from the left and right channels is better aligned leading to stable images. That something may be the 'better' or more correct set of harmonics presented to the left and right and combining at the listening position, I speculate. The effect is the same in various listening locations around the room.

Elk
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Re: DBT testing

WTL,

Exactly my experience and I like your hunch.

My guess is that it relates to timing, but this is merely my attempt at offering a partially refined hunch.

Electricity is fascinating stuff.

dcstep
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Re: DBT testing

WTL, I can hear what you describe, but the thing I note has nothing, or little, to do with image. What I hear is for a single instrument, like a bass, I can hear an improvement in the definition and separate identity of the harmonics that color the fundemental. With lesser resolution, the note sounds roughly the same, but the harmonics and fundemental are balled together.

I DO think Elk is right in that it's reduction of some sort of timing anomaly, perhaps reduction of IMD.

Dave

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Re: DBT testing


Quote:
WTL, I can hear what you describe, but the thing I note has nothing, or little, to do with image. What I hear is for a single instrument, like a bass, I can hear an improvement in the definition and separate identity of the harmonics that color the fundemental. With lesser resolution, the note sounds roughly the same, but the harmonics and fundemental are balled together.

I DO think Elk is right in that it's reduction of some sort of timing anomaly, perhaps reduction of IMD.

Dave

Man, if only DBT didn't turn off your ability to hear that!

If only Tiger Woods were an audiophile. I bet he could hear it despite the crushing and insurmountable horrors of listening blind.

Dave, have an audio buddy switch without you knowing which cable is in and listen for a few days between changes (or not) and see after a dozen or so trials how it goes.

I'd love if you could be "The One."

dcstep
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Re: DBT testing

Buddha, this is just for my own enjoyment and my own purse, so I'm very happy with the results. It's actually pretty easy to hear.

The problem is measuring. If we could empirically measure this effect, then DBT wouldn't even be an issue. Ethan's claim that FR would reveal this is over simplified. The Colorado Audio Society has a spectrum analyser that I can probably borrow. Maybe I can see some differences with very close comparative miking fed into the analyser. Maybe I'll record and A-B at 5.6mHz with my DSD recorder and then compare the out recordings on the analyser.

Dave

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Re: DBT testing


Quote:
Ethan's claim that FR would reveal this is over simplified.


Regarding wires, what else besides frequency response (and possibly distortion) is there?


Quote:
Maybe I'll record and A-B at 5.6mHz with my DSD recorder and then compare the out recordings on the analyser.


There you go! Please report what you find.

--Ethan

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Re: DBT testing


Quote:
WTL, I can hear what you describe, but the thing I note has nothing, or little, to do with image. What I hear is for a single instrument, like a bass, I can hear an improvement in the definition and separate identity of the harmonics that color the fundemental. With lesser resolution, the note sounds roughly the same, but the harmonics and fundemental are balled together.

I DO think Elk is right in that it's reduction of some sort of timing anomaly, perhaps reduction of IMD.

dcstep,

The image improvement is only one of the things I heard. Improved instrument resolution is another. Low-level detail also improved. There's more 'life' to a singer's voice, which probably is equivalent to the improved instrument resolution. There's even more.

Yes, you and I may have heard similar effects.

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Re: DBT testing


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... The Colorado Audio Society has a spectrum analyser that I can probably borrow. Maybe I can see some differences with very close comparative miking fed into the analyser. ...

One could get software on a computer that makes it a spectrum analyzer. Perhaps that is another option. I've considered it but not acted on it.

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Re: DBT testing

What is on eithr side of the connectors AFTER the magic wire? If you have 10 feet of magic, then to a non magic conenctor, on the inside of the comopents at the ends, I bet there is either standard hookup wire, or some otehr non magic conenction. Why would magic in the middle of all this non magic stuff, perform.....wellllll, magic on what you hear, is the magic in teh wires more poerful than the non magic at teh other ends? Now this is getting like good over evil Ying over the other Chinese brother oh, sum ting WONG, cus' again, what you are claiming to hear doesn't make any sense....did you perhaps see any colors in a rainbow while you where listening to all this improved RESOLUTION? I think you may be OD'ing on too many SKITTLES!!!! Better ckts, mean better amplifeirs, that gives ya better sound, just like Pizzza.

dcstep
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Re: DBT testing

Huh???

I think DUP confused his threads.

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Re: DBT testing


Quote:
Huh???

I think DUP confused his threads.

Maybe, but he doesn't seem to care.

He just hits a button for a word stew post related to one of his 6 topics.

That reply could be his response to any topic.

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Re: DBT testing


Quote:
I think DUP confused his threads.


How can you tell?

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Re: DBT testing


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What I hear after circuit modifications on my own gear is that the instruments are better individualized apart from one another instead of having one instrument's sound interfere with another. Spatial localization of each instrument seems to be more stable than before.

This is what I mean when I say the sound of an instrument appears from the background mix...clear and in pace.

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Re: DBT testing


Quote:
What is on eithr side of the connectors AFTER the magic wire? If you have 10 feet of magic, then to a non magic conenctor, on the inside of the comopents at the ends, I bet there is either standard hookup wire, or some otehr non magic conenction. Why would magic in the middle of all this non magic stuff, perform.....wellllll, magic on what you hear, is the magic in teh wires more poerful than the non magic at teh other ends? Now this is getting like good over evil Ying over the other Chinese brother oh, sum ting WONG, cus' again, what you are claiming to hear doesn't make any sense....did you perhaps see any colors in a rainbow while you where listening to all this improved RESOLUTION? I think you may be OD'ing on too many SKITTLES!!!! Better ckts, mean better amplifeirs, that gives ya better sound, just like Pizzza.

CUCKOO FOR COCOA PUFFS!! CUCKOO FOR COCOA PUFFS!! BRAAAWWWKK! WHO'S YER MOTHER?!

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Re: DBT testing


Quote:
This is what I mean when I say the sound of an instrument appears from the background mix...clear and in pace.

Maybe we're describing a similar observation.

In live music one can hear each instrument separate from another. In a band, one can hear the drums behind the guitar beside the bass, and focus on any one separately and hear them distinctly.

Often in reproduced music, the instruments appear to sound blended in a some way, but discernable as different from the live in that way. One of the differences is that the sound is less blended after the modification than before, so closer to the live sound. And of course the other aforementioned effects of improvement also help the illusion of liveness. Based on the comparison to the character of the live sound, this difference is an "improvement".

At the same time, there is what I interpret as a slight reduction in the treble energy, but does not sound like a HF roll-off. Some might call it cleaner 'highs', and it seems to sound cleaner. One way to describe it is that there's much less of the sound that resembles an on-going hint of glass-breaking riding over the treble range.

Hope you can describe the effects better.

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Re: DBT testing

In my case the things that are most noticable in power line changes is sme instruments, noteably with high treble, like triangles, etc, emerge from a background of sort of jumbles instruments. They may already be there but they are not notable or separate in place. In addition, the high signals are much more clear. I may have a simliar effect on the lows but my speakers have a reduced low end so I do not note it. Castinets go from sort of a ceramic sound, almost wood like, to a shimmery metalic with a noticable decay that wass missing before the power upgrade. Lots of folk don't believe such things are possible. I believe they lack the ability to discern such changes.

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Re: DBT testing


Quote:
instruments, noteably with high treble, like triangles, etc, emerge from a background of sort of jumbles instruments.


Those high frequencies are affected the most by positional comb filtering. This happens even in professional recording studios and other professional monitoring environments. If you move your head just half an inch, the different arrival times from the left and right speakers cause large changes in frequency response. At 7 KHz, one quarter wavelength is less than half an inch, and that's all it takes to go from a peak to a deep null. I'm sure this is what you're hearing, not the result of anything related to AC power.

--Ethan

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Re: DBT testing

Then why did it and does it change with power cord changes. ame chair, same source, same CD, same distance from the speakers...I measure to insure my listening position is withing 1/4 inch

Elk
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Re: DBT testing

Ethan, what changes are significant enough that they are not due to comb filtering and how - without measuring - does one know this?

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Re: DBT testing

Throw your headphones on if you're wondering if a change is due to a system change or due to comb filtering. It's usually due to the system, but Ethan's right (to a small degree) that comb filtering can trick you sometimes.

Dave

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Re: DBT testing


Quote:
what changes are significant enough that they are not due to comb filtering and how - without measuring - does one know this?


Measuring trumps subjective opinion every time. And anything that affects the timbre of a triangle (or any other instrument) can be easily measured. But not everything needs to be tested blind! I'd say 6 dB of shelving boost or cut, either treble or bass, is easy to hear and identify with certainty every time. Even 3 or 4 dB can be heard fairly easily, though of course it depends on the music playing at the time. You can adjust a bass shelving control from full cut to full boost and not necessarily notice it when only a triangle is playing. But in this case, what Jim described is exactly what happens with slight changes in position.

Bottom line - all changes in timbre can be easily measured because timbre is frequency response. If cable or power line products really did affect timbre, those vendors would have frequency response graphs all over their web sites proving their product is better than other brands. Or in the case of power conditioners, better than no power conditioner. But they never have anything other than fancy prose to describe the benefits.

--Ethan

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Re: DBT testing

Perhaps, but the changes exist

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Re: DBT testing

As mentioned further up the thread, there's more to the souond quality of a note than timbre. FR can measure changes in timbre, but not changes in the quality of the resolution of the note, including such things as the separation of the harmonics that make up the timbre.

This quality might be measurable, perhaps a reduction in IMD, but FR will not show it. Interestingly, these are the qualities that we're likely to hear as we change cables.

Dave

zane9
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Joined: Jan 7 2008 - 6:37pm
Re: DBT testing


Quote:

Measuring trumps subjective opinion every time.--Ethan

Well that's just heresy, I tell you. Grab the torches and pitchforks! Assemble the Inquistors. Boil the oil.

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