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ethanwiner
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Re: DBT testing


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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.


I'm sorry Dave but that simply is not correct. A note is comprised of a fundamental and its harmonics, and the balance between those components does indeed fall under frequency response. Now, all of these components can and do vary over time. Harmonics of percussion and plucked string instruments typically decay over time faster than the fundamental decays. This is due to losses in the string (or metal in a triangle) that damp the highs more than lows. And when played softly, the harmonics are at a lower level than when playing loudly. But this does not change the basic relation of timbre to frequency response. That is, there's no such thing as "quality of the resolution of the note."

Wire has three properties - resistance, capacitance, and inductance. Together these three properties create a filter. And a filter affects frequency response. There is no way that a cable can do more than alter the frequency response (or possibly slew rate), and no way a cable can do anything that is not easily measured.

--Ethan

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Re: DBT testing


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


Typical response from a believer. Hey, don't shoot the messenger!

(I assume you were kidding...)

--Ethan

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Re: DBT testing


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(I assume you were kidding...)

--Ethan

Of course I was kidding! Some days it feels like we are living in the 12th. century: audio anti-science abounds.

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Re: DBT testing


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Measuring trumps subjective opinion every time.

Mmmmmmmmmm, sounds like fun.

I think maybe I'll go objectively measure Kind of Blue tonight instead of subjectively listening.

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Re: DBT testing


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I think maybe I'll go objectively measure Kind of Blue tonight instead of subjectively listening.

Easy there. It might become Sort of Blu-ish.

ethanwiner
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Re: DBT testing


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I think maybe I'll go objectively measure Kind of Blue tonight instead of subjectively listening.


That's silly, and I've addressed that here before many times. Of course you cannot "measure" musicianship or orchestration or quality of a composition. That's not the issue here. We're talking about how a piece of wire changes electrical signals that pass through it. Please man, I love you like a brother, but that's a straw man argument and you know it.

--Ethan

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Re: DBT testing


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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

I support you Dave,

Frequency response can change the resolution of the sound, but then the sound will not be the same because the harmonic structure is different, as I believe you indicate. So if the sound is the same, except better inner detail/delineation, as you indicate, then something other than frequency response is the cause.

For instance, dielectric absorption and equivalent series resistance in a capacitor causes it not to charge nor discharge instantaneously, but causes the energy to "dissipate" over time, thus smearing the inner detail. It will not change the timbre or frequency response.

Nice post DC.

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Re: DBT testing


Quote:

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I think maybe I'll go objectively measure Kind of Blue tonight instead of subjectively listening.


That's silly, and I've addressed that here before many times. Of course you cannot "measure" musicianship or orchestration or quality of a composition. That's not the issue here. We're talking about how a piece of wire changes electrical signals that pass through it. Please man, I love you like a brother, but that's a straw man argument and you know it.

--Ethan

Ethan, my love for you is reciprocal.

However, I am not a measurement guy.

Now, that doesn't mean I don't think we should be rigorous about claims we make.

For me, the line is drawn not at the measuring bench, but in the listening environment.

I am dubious as to the seemingly all pervasive "DBT Deafness" we hear so much about.

What would be cool to do with DBT is to actually try and explore the phenomenon looking for the point at which sonic differences are able to overcome this debilitating malady.

That would be of great interest to me.

It would also be a situation where we could compare degrees of measured difference with the ability to perceive those differences.

I've heard of some 0.2 dB threshold of audibility for some sonic changes in DBT, so I look at the astounding sonic claims that vanish with DBT and currently just file them in the 'less than 0.2 dB change' category.

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Re: DBT testing


Quote:

Quote:
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.


I'm sorry Dave but that simply is not correct. A note is comprised of a fundamental and its harmonics, and the balance between those components does indeed fall under frequency response.

You're not listening Ethan. I'm talking about the same harmonics, but with higher resolution they're not smeared together. You hear the ringing of the various harmonics more separately. FR will not tell you whether they're smeared together or not.

Why do you stick to your simplistic model, of trying to explain everything with FR and comb filtering. I DO think these effect can be measured, but your approach is a dead end.

Did your uncle work for Stereo Review??

Dave

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Re: DBT testing


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I support you Dave,

Frequency response can change the resolution of the sound, but then the sound will not be the same because the harmonic structure is different, as I believe you indicate. So if the sound is the same, except better inner detail/delineation, as you indicate, then something other than frequency response is the cause.

For instance, dielectric absorption and equivalent series resistance in a capacitor causes it not to charge nor discharge instantaneously, but causes the energy to "dissipate" over time, thus smearing the inner detail. It will not change the timbre or frequency response.

Thanks for reading with an open mind.

Jeff Rowland agrees with you about the impact of dielectrics and how we perceive it. He also thinks that he hears these things we're discussing but hasn't successfully measure it. (Based on my past discussions with Jeff).

Dave

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Re: DBT testing


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You're not listening Ethan. I'm talking about the same harmonics, but with higher resolution they're not smeared together.


I am listening, but I disagree with the words you use because they make no sense grammatically or scientifically. What specifically does "smeared together" mean? To me that's as meaningless as Pace, Rhythm, and Timing.


Quote:
You hear the ringing of the various harmonics more separately. FR will not tell you whether they're smeared together or not.


Again, those words are meaningless. Harmonics don't "ring" - they simply sound for as long as the musical source creates them. Did you ever watch a plucked guitar string on an oscilloscope? The note starts suddenly, with strong harmonic content, and the fundamental and harmonics decay over time. Usually at different rates.


Quote:
Why do you stick to your simplistic model, of trying to explain everything with FR and comb filtering.


Because this is the correct model!


Quote:
I DO think these effect can be measured, but your approach is a dead end.


Then please explain exactly what you would measure. And for gosh sakes, I hope you'll be as detailed as possible!

--Ethan

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Re: DBT testing

How would you go about measuring frequency response? I have no microphone or measuring tools of any kind like an oscilloscope.

ethanwiner
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Re: DBT testing


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How would you go about measuring frequency response? I have no microphone or measuring tools of any kind like an oscilloscope.


Great question Alex.

Ideally you'd have a sine wave oscillator to send through the device under test (DUT), and an accurate voltmeter for measuring the output. But there's a much easier way to test this stuff, that will also determine distortion and all other degradation. The key is to record the signal at the speaker terminals. Yes, this requires a computer and decent sound card to record to, and probably half a dozen resistors to pad down the high speaker output to line level. But most of us have a computer and sound card, and there's decent freeware software. If you or anyone else is up for legitimate scientific testing, I'll gladly build and mail out a pad / adapter that clips onto speaker terminals at one end and has a pair of RCA plugs at the other.

The idea is you play a CD through your system, and record the signal at the speaker terminals. This way the recording is influenced by every device and wire in the entire path. Then you can change any component, such as an RCA cable or power cord etc, record again, and use software to compare the two files. Specifically, my approach is to subtract one file from the other. This is called a Null Test. If both files are identical, the result is total silence. If there's 0.1 percent distortion, there will be some residual signal but it will be 60 dB softer than the source files. In other words, all that will remain is the distortion, or other difference.

The beauty of a null test is you don't even have to know what you're looking for. Any differences in the files will show up after nulling. If one file has more or less treble, then only treble will remain after nulling. Likewise for bass, and anything else you can imagine. So if someone is certain that replacing a power cord increases clarity, a null test will establish whether the increased clarity is real or imagined.

So who's up for this?

--Ethan

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Re: DBT testing

This test does not take into account speaker interactions that may influence the frequency response one hears when changing components.

ethanwiner
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Re: DBT testing


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This test does not take into account speaker interactions that may influence the frequency response one hears when changing components.


Sure it does. It accounts for the entire signal path right up to the speaker terminals. Now, you're correct that it won't account for moving the speakers, toe in, etc. But anything else you change in the signal path is included.

You mention changing components. I envisioned this test mostly for learning if wire changes the sound as JIMV suggests. If you change a component, such as CD player, that will likely affect the volume level. And volume changes prevent a Null Test from working. However, that could be compensated for in software. Artifacts from the "minor math" needed to raise or lower a signal a few dB will probably be well below -80 dB.

--Ethan

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Re: DBT testing

I think Ethan's on the right track.

The recording of a some music over time eliminates the possibility of timing changes that might not be revealed through measuring just the frequency response of the system.

Taking the measurement at the speaker terminals does include the influences of the speakers in the circuit. Electricity does not move in one direction only in a circuit. Rather in a sense it just "is". Thus you can tap into the circuit at the speaker terminals, or at the amp's output, and get the same result.

The null test will reveal even the tiniest differences in the wave form. You have to remember not to make any changes to the system then what you want to test however. A small nudge of the volume knob sill mess things up. As Ethan indicates you can compensate for this, but it is better not to need to.

The first thing I want to see is changes in PRaT with a change of wire.

Dave, your Korg is perfect for this sort of thing.

(As a side note, my research years ago on vibrating strings demonstrated that the harmonics of a plucked string always die out much faster than the fundamental.

The most fascinating to watch however is the decay of a piano note. With multiple strings for each note there are amazing, complexe interactions that take place between the strings. Dampening two so that only one string is allowed to vibrate changes everything. No wonder una corda sounds so different in addition to being quieter.)

ethanwiner
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Re: DBT testing


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The null test will reveal even the tiniest differences in the wave form.


Exactly, including things that "science doesn't yet know how to measure" which I often see believers claim. So even if it were true that everything about audio is not known, a null test will still reveal every difference including frequency response, distortion, added artifacts, and anything else that changed.


Quote:
my research years ago on vibrating strings demonstrated that the harmonics of a plucked string always die out much faster than the fundamental.


Yes, and I mentioned that above. If you want to learn how audio really works, nothing beats watching waveforms on an oscilloscope.

I probably didn't mention it here, but I recently made a video showing how to program old-style analog synthesizers. The key to understanding is being able to see the waveforms on a 'scope. I've wanted to do this video for years, but I haven't had an oscilloscope since the 1980s. I recently found a plug-in version, and was finally able to make the video. The video relates to this thread only peripherally, but it does explain harmonics, resonance, and more, and lets you see and hear what's going on. If anyone cares, here it is:

http://www.vimeo.com/1309545

--Ethan

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Re: DBT testing


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If you want to learn how audio really works, nothing beats watching waveforms on an oscilloscope.


Plus, it's fun!


Quote:
I probably didn't mention it here, but I recently made a video showing how to program old-style analog synthesizers.


Cool! I'll take a look.

I first learned to work with analog synthesizers on an ARP 2600, back when they first came out. Three oscillators, monophonic, simple envelopes, subtractive synthesis. I loved this thing and learned a tremendous amount about acoustics this way. It wasn't until years later that I learned that the original Blue Meanie was not this synthesizer. IIRC, R2D2 was voiced by an ARP 2600 with help from its random frequency generator.

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Re: DBT testing

Ethan, if you can't hear the harmonics separate from the fundemental, then I can't help you. In real life, if you focus and listen, you can hear the harmonics "ringing" (all notes ring dumb ass). A good system will maintain the ability to hear the separate harmonics and a poorer system will smear them together. (Several readers here know what I'm talking about and you're either playing dumb or...).

You're model is not complete. It's simplistic and ignores what many observe. You only seem to observe what you've figured out how to measure and seem to think that if you can't measure it then no one can. That's simply not the case.

BTW, you can't exclude the speaker from a speaker/cable interface measurement. You're ignoring all the EMI that the speakers generates, which is substantial.

Dave

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Re: DBT testing


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IIRC, R2D2 was voiced by an ARP 2600 with help from its random frequency generator.


Toward the end of my video I show making a robot voice using random values on a formant filter.

--Ethan

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Re: DBT testing


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Ethan, if you can't hear the harmonics separate from the fundemental, then I can't help you. In real life, if you focus and listen, you can hear the harmonics "ringing"


Of course I know about and hear harmonics. I've been a professional musician and recording engineer for 40 years.


Quote:
A good system will maintain the ability to hear the separate harmonics and a poorer system will smear them together.


That still says nothing. What exactly does a "poor system" do to make harmonics less audible? And how is that different than simply reducing higher frequencies, which is what harmonics are? And again I ask you what "smear" means. Please be very specific!


Quote:
You're model is not complete.


Then complete it for me!


Quote:
you can't exclude the speaker from a speaker/cable interface measurement. You're ignoring all the EMI that the speakers generates, which is substantial.


Let me guess, EMI also smears harmonics, right?

Dave, I don't know what else to tell you. You seem unable to elucidate where I'm wrong, yet you insist I'm wrong anyway. Did it ever occur to you that maybe frequency response, distortion, and noise are all there is?

--Ethan

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Re: DBT testing

I think the missing function not being specifically mentioned is time. Distortion and noise can vary over time with input. My guess is that what Dave hears as smearing are a result of these differences.

I know what he means, some systems have a certain clarity that really allows hearing timbre, subtle harmonic difference tones, etc.

I haven't been satisfied with summary measurements to distinguish the equipment that is more transparent. Not because we can't measure it - I believe we can - but that what we normally see are THD, IM, etc. These can be very similar and vanishingly low, yet some pieces sound much better.

I am sure that these differences can be seen on a null test. I don't hear this sort of change with wire however, but readily have heard them with certain preamps in particular.

By suggesting a null test Ethan is, I believe, implicitly recognizing that frequency response, noise and distortion are heard by as as a function of time.

None of these are absolutely fixed, but are part of a dynamic process. Finding a way to test and measure a piece of equipment as a dynamic system as it reproduces a real musical signal may be the trick.

As I understand it, the specs that we see published are based on a static signal and often at a single frequency and level. This may be why the measurements can be the same and yet we can hear differences.

ethanwiner
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Re: DBT testing


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I think the missing function not being specifically mentioned is time.


When I mention the four basic parameters I almost always include time, along with frequency response, distortion, and noise. But since I thought we were discussing wire at the moment, I purposely left that out. Time-based artifacts like wow and flutter are a problem, but this is not affected by wire. Yes, jitter possibly could be affected by wire, but jitter is a non-issue so I don't bother including it.


Quote:
I know what he means, some systems have a certain clarity that really allows hearing timbre, subtle harmonic difference tones, etc.


Yes, I agree! But that clarity is purely a function of frequency response.


Quote:
I am sure that these differences can be seen on a null test.


You betcha.


Quote:
Finding a way to test and measure a piece of equipment as a dynamic system as it reproduces a real musical signal may be the trick.


Yes, and this is exactly what a null test does. After subtracting one file from the other, you have a history of all differences over time in the result file.

--Ethan

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Re: DBT testing

Yesterday three of us compared four high end power chords in a $80k system. The cords ranged in price from around $200 to $2000. We compared comments after the fact. We all agreed that every cable sounded different and we all recorded similar descriptions of what we heard. I was one of the observers, the other was a blind gentleman that is classically trained as a pianist and the other was a trained vocalist that spent over thirty years in the audio business.

These comparisons literally took seconds. My confidence is extremely high that we were hearing real differences in the sound and the agreement was very close.

I agree with Elk that with more sophisticated measurement we can measure this. However, I don't think that Ethan's simplistic FR measurements will be revealing enough.

It's may be a month or two away, but I promise to borrow the Colorado Audio Societies spectrum analyser and doing some detail spectal analysis comparisons at the speakers. There's something going on there and I think it'll be visible in such a comparison.

BTW, has Stereophile ever tried this? I don't recall ever seeing a comparison of cables in a system.

Dave

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Re: DBT testing


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Yes, jitter possibly could be affected by wire, but jitter is a non-issue so I don't bother including it.

When did jitter become a non-issue??? This is another Ethanism, he can't explain it so it doesn't exist.

He's trying to make the whole world of distortion fit into his simplistic FR model. It doesn't work.

Dave

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Re: DBT testing


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My confidence is extremely high that we were hearing real differences in the sound and the agreement was very close.


Excellent, now let's assess it again scientifically and see if you can be proven correct.


Quote:
I promise to borrow the Colorado Audio Societies spectrum analyser and doing some detail spectal analysis comparisons at the speakers.


Actually, a spectrum analyzer is not the right tool for this for several reasons. One reason is it displays the instantaneous spectrum at that moment, so using it to compare two separate passes is very difficult. How would you play the exact same 1/4 millisecond of audio both times with each power cord? Another possible limitation may be the analyzer itself. If it's a typical third-octave type, that is way too coarse to see fine detail. Yet another limitation is you may not be able to identify subtle content 80 dB below the music. Again, this depends on the specific analyzer.

The best way to do this is with a null test as I described. Do you have a computer and sound card with stereo line level inputs? Or a good quality DAT recorder? If so, let me know your address (email me from the RealTraps site) and I'll build and mail you the adapter cable I described earlier. This way there is no chance that we're looking for one thing (frequency response) when something else (who knows what) is responsible for the change you hear with different power cords. Another advantage of actually recording the signal with each power cord is the spectrum can be analyzed via sophisticated software after the fact. We could even use the recordings as a blind test here in the forum, and let people try to identify which cord is which, or if they hear a difference at all.

--Ethan

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Re: DBT testing


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When did jitter become a non-issue???


About 20 years ago.

Actually, I'm not convinced jitter was ever an issue. But I don't have any digital recording gear that old to audition or measure. Some say jitter was a problem with very early converters, though personally I'm skeptical jitter was ever audible. It's like dither - you can measure it, we all know what it does and can explain it fully, but in practice it makes no audible difference.


Quote:
This is another Ethanism, he can't explain it so it doesn't exist. He's trying to make the whole world of distortion fit into his simplistic FR model. It doesn't work.


Dave, I have $100 that says you have no idea what jitter sounds like, have never heard it, and could not distinguish severe jitter from no jitter. Heck, when did I ever say I can't explain jitter? I know exactly what jitter is, and I know exactly what causes it! Do you?

Further, I never said jitter manifests as a frequency response error. In fact, jitter creates noise side bands typically 110 to 130 dB below the signal. Think about that! This is 10 to 40 dB below the noise floor of a CD, which in turn is typically 10 to 30 dB below the noise floor of the recording itself.

Dave, I try hard to be polite and respectful, even when I know people are talking out their butt as happens often in all audio forums. If you disagree, then the burden is on you not just to say I'm wrong, but to explain why I'm wrong and also explain what is right. You haven't done that once. If you can explain what jitter sounds like, and tell me why you're certain that what you heard was actually jitter and not something else, that $100 is yours. No kidding.

In the mean time, you may find these articles interesting:

Artifact Audibility Report
Dither Report

--Ethan

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Re: DBT testing

Nonetheless, I'm going to try spectrum analysis. I can use my 5.6mHz DSD recorder to record the same recorded musical passages at the speaker and then overlay them in a computer, hopefully. Since the signal will start at the same point, it should be relatively easy to line them up against each other. Hopefully I can figure out how to overlay them.

Dave

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Re: DBT testing

This sounds perfect.

I would take Ethan up on his offer for a pad to connect the speaker terminals to the Korg. This makes the test completely repeatable and includes the entire system in the test.

Since spectrum analysis is an analysis of the entire input but presented as single picture, be sure that the files are precisely the same length, and begin and end at the same point in the music. Even just a bit more on either end of the file will skew the results.

Audacity has a spectrum analyzer built in, although I have not played with it to know how well it works or how versatile: Free Download Audacity itself is a great free package.

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Re: DBT testing


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be sure that the files are precisely the same length, and begin and end at the same point in the music.


That's not really needed. In Sound Forge you can select any section of a file and run the spectrum analysis. If I were analyzing two files I'd simply highlight the same part in both files, then call up the analyzer. Likewise for doing a null test. I'd import both files into Sonar on separate tracks, then align them at the sample level. If one starts sooner or goes longer, it's easy to "slip edit" the excess. Or just start Play (or render) over a region common to both files.

--Ethan

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Re: DBT testing

I was trying to indicate to Dave that he needs to do exactly as you describe before overlaying the spectra for comparison.

We are on the same page.

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Re: DBT testing


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We are on the same page.


Okay, gotcha!

--Ethan

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Re: DBT testing


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FR will not tell you whether they're smeared together or not. Why do you stick to your simplistic model, of trying to explain everything with FR and comb filtering.


The last two issues of AudioXpress magazine contain an excellent two-part article on speaker parameters by famed speaker designer Joseph D'Appolito. I assume most people here have heard of him? In the conclusion he states what I've been saying all along. I won't type the entire conlusion into this post, but this part is relevant:


Quote:
... the single best predictor of loudspeaker listener preference is frequency response ... resonances are the principle causes of objectionable sound ... Unless distortion levels are very high, harmonic and IM distortions are not strong predictors of listener preference, but they are useful in assessing driver quality and can explain why speakers sound bad when played at high volume levels.


In this case he's talking about speaker resonance, but the same applies to room resonance.

It would be really fun to discover some new, previously unknown, parameter that affects sound quality and clarity. But that's not likely to happen since the four parameters we already know can predict with certainty what sounds good and what does not sound good. I found his comment about distortion not being hugely important interesting, because I've always felt that small amounts of distortion can enhance the sound of some types of music. Hence the popularity of gear like tube amps that have more distortion than solid state amps yet are preferred by some people.

--Ethan

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Re: DBT testing


Quote:

Quote:

I support you Dave,

Frequency response can change the resolution of the sound, but then the sound will not be the same because the harmonic structure is different, as I believe you indicate. So if the sound is the same, except better inner detail/delineation, as you indicate, then something other than frequency response is the cause.

For instance, dielectric absorption and equivalent series resistance in a capacitor causes it not to charge nor discharge instantaneously, but causes the energy to "dissipate" over time, thus smearing the inner detail. It will not change the timbre or frequency response.

Thanks for reading with an open mind.

Jeff Rowland agrees with you about the impact of dielectrics and how we perceive it. He also thinks that he hears these things we're discussing but hasn't successfully measure it. (Based on my past discussions with Jeff).

Dave

Jeff won't be able to because the resolution of existing equipment is not sufficient.

Even different tubes can display a smearing of the sound/harmonics. Compare an amperex bugleboy 6dj8 and JJ E88cc (european number of 6dj8). The amperex will have more concise placement of a singer even though both measure the same frequency response, 20-20khz, when using a sine wave. Harmonic distortion of both tubes is at least -60db 2nd harmonic as well. Many if not most manufacturers take into account what brand tube is being used when designing.

As you know, but for newbies, textbooks only teach the basics and not all there is to know about any discipline, electronics included. A text book is not the totality of all information but basics to get started.

Hope this helps.

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Re: DBT testing


Quote:
I suggest that it is as much fantasy to expect that measurements can predict sound quality as it would be to think that they could predict the quality of music. All that the reductionism inherent in scientific method can do is to look after the fact for possible explanations for what is heard. And if amplifiers can sound different, it isn't necessary to invoke black magic, mysticism, or as-yet-unknown performance parameters as explanations. Architect Mies van der Rohe once said of his craft: "God is in the details." (footnote 5) When it comes to amplifier sound quality, the subjective differences are in the measured details. And the way in which to perceive how all those details interact and thus affect the sound of the music is simply to listen. Listening enables the whole of a component's performance to be examined simultaneously.

Pulled from JA's article- I could not agree with John more. High end audio is the reproduction of music (an art form) at home. And just as music, and the instruments that create the art in the first place can not be proven better through measurement, neither can the whole of an audio system be quantified by mere measurement.

It's as simple as that.

Yours in music,
Ted Denney III Lead Designer Synergistic Research Inc.

ethanwiner
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Re: DBT testing


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High end audio is the reproduction of music (an art form) at home. And just as music, and the instruments that create the art in the first place can not be proven better through measurement, neither can the whole of an audio system be quantified by mere measurement.


The fundamental flaw in that thinking is confusing music production with audio reproduction. The first is an art, the second a science. Musical instruments have intentional sound qualities and character. For example, violins and cellos have numerous high-Q resonances that are different for every instrument. These resonances are what distinguish a Strad from a cheap plywood imitation.

An audio amplifier, on the other hand, has one job and one job only - to reproduce at its output as closely as possible what you present to its input. And that is easily assessed using test gear.

--Ethan

Ted_D
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Re: DBT testing


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Musical instruments have intentional sound qualities and character. For example, violins and cellos have numerous high-Q resonances that are different for every instrument. These resonances are what distinguish a Strad from a cheap plywood imitation.

As well as unintentional sound qualities- there is no conclusive way to prove (or disprove) one musical instrument of seeming excellent quality better then the next (also of seeming excellent quality) without subjective listening. This is why we cannot reproduce many of the coveted instruments of the past. That we can distinguish a Strad from a cheap plywood imitation as a basis for your argument serves only to illustrate your understanding of, and approach to, audio.


Quote:
An audio amplifier, on the other hand, has one job and one job only - to reproduce at its output as closely as possible what you present to its input. And that is easily assessed using test gear.


And just as with musical instruments, amplifiers (and all other components) have intended sound qualities, as well as unintended qualities. And just as with musical instruments, any final assessment pertaining to sound quality is based on subjective criteria. This is simply a result of the different sonic characteristics of the internal components (capacitors, resistors of different compositions but of equal value, transformers, circuit layout, etc) that go into making amplifiers, pre-amplifiers, digital components, turntables, and so on. Perhaps in your view there is "perfect sound forever," but this does not ring true to my ears.

http://forum.stereophile.com/forum/showf...art=35&vc=1


Quote:
I am quite certain that a 6-foot $5 RCA wire from Radio Shack is as good as is needed, and any wire that sounds different is only making things worse.

And I'm totally certain that all replacement AC power wires are bullshit. When people believe they hear a difference they are wrong.

--Ethan

http://forum.stereophile.com/forum/showf...art=34&vc=1

Quote:

Quote:
How about it, Ethan, when did audio reach stasis?


For everything except loudspeakers (and rooms), at least 20 years ago.

--Ethan

Ethan I am proud to say you and I could not differ more in our understanding of, and approach to, audio.

Yours in music,
Ted Denney Lead Designer Synergistic Research Inc.

Jan Vigne
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Re: DBT testing


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The fundamental flaw in that thinking is confusing music production with audio reproduction. The first is an art, the second a science. Musical instruments have intentional sound qualities and character. For example, violins and cellos have numerous high-Q resonances that are different for every instrument. These resonances are what distinguish a Strad from a cheap plywood imitation.

The flaw that fundamentally runs through all of your posts, Winer, is you strive to be the ultimate reductionst just as you prefer to be seen as the ubber-cynic. In this case you reduce the art form to the resonances within the instrument itself and have no accord for the musician.

Place a $300 Epiphone Dot in the hands of B.B. King and you still have B.B. King. Place a $3000 Gibson Lucille in the hands of a beginning guitar student and you still have a beginning student. You cannot remove the human being from the art form whether live or reproduced.

The experience is in the person not in the instrument and cannot be described by test instruments. I was reading a book on Delta Blues musicians and one professorial type studied with exacting instruments the micro-deviations in timing produced by Muddy Waters each time he played the same song. The professor thought he had discovered the secret to Water's performance style, recalling the African poly-rhythms from which Blues came to the guiding spirit of Water's performance. He never once stopped to realize what Waters played was meant to be entertaiment. Anyone who just listened to Muddy Waters could have told him what he spent months trying to decode with his test gear.

It's not what you measure with equipment, it's what you hear and feel that matters.

rvance
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Re: DBT testing

IMO,the truly developed, scientific mind would recognize the inadequacy of applying these reductionist methods to areas of such complexity as music, audio and perception.

So what kind of person NEEDS this illusion of control?

What kind of person NEEDS to believe they can quantify, fragment, reduce, compartmentalize, measure and mechanize these elements of experience that only exist in their truest form as a whole?

What kind of person NEEDS to simplify, subordinate and dominate the objects of their experience and then insist they better understand their world in all its disconnected pieces and parts?

doctormax
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Re: DBT testing


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IMO,the truly developed, scientific mind would recognize the inadequacy of applying these reductionist methods to areas of such complexity as music, audio and perception.

So what kind of person NEEDS this illusion of control?

What kind of person NEEDS to believe they can quantify, fragment, reduce, compartmentalize, measure and mechanize these elements of experience that only exist in their truest form as a whole?

What kind of person NEEDS to simplify, subordinate and dominate the objects of their experience and then insist they better understand their world in all its disconnected pieces and parts?

--Ethan Wiener ?

Jan Vigne
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Re: DBT testing


Quote:
IMO,the truly developed, scientific mind would recognize the inadequacy of applying these reductionist methods to areas of such complexity as music, audio and perception.

So what kind of person NEEDS this illusion of control?

What kind of person NEEDS to believe they can quantify, fragment, reduce, compartmentalize, measure and mechanize these elements of experience that only exist in their truest form as a whole?

What kind of person NEEDS to simplify, subordinate and dominate the objects of their experience and then insist they better understand their world in all its disconnected pieces and parts?

Winer?

How'bout that! I didn't see your reply until mine posted.

ethanwiner
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Re: DBT testing


Quote:
there is no conclusive way to prove (or disprove) one musical instrument of seeming excellent quality better then the next


Yes, exactly.


Quote:
amplifiers (and all other components) have intended sound qualities, as well as unintended qualities.


The only intended "quality" should be total transparency. Anything else is not high fidelity in any way one could define "fidelity." I'm pretty sure "fidelity" is even defined that way in the dictionary.

Ah, HERE it is:


Quote:
accuracy with which an electronic system reproduces the sound or image of its input signal


Quote:
just as with musical instruments, any final assessment pertaining to sound quality is based on subjective criteria.


Sorry, no.


Quote:
I am proud to say you and I could not differ more in our understanding of, and approach to, audio.


Equally proud, right back atcha.

--Ethan

Ted_D
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Re: DBT testing


Quote:

Quote:
Musical instruments have intentional sound qualities and character. For example, violins and cellos have numerous high-Q resonances that are different for every instrument. These resonances are what distinguish a Strad from a cheap plywood imitation.

As well as unintentional sound qualities- there is no conclusive way to prove (or disprove) one musical instrument of seeming excellent quality better then the next (also of seeming excellent quality) without subjective listening. This is why we cannot reproduce many of the coveted instruments of the past. That we can distinguish a Strad from a cheap plywood imitation as a basis for your argument serves only to illustrate your understanding of, and approach to, audio.


Quote:
An audio amplifier, on the other hand, has one job and one job only - to reproduce at its output as closely as possible what you present to its input. And that is easily assessed using test gear.


And just as with musical instruments, amplifiers (and all other components) have intended sound qualities, as well as unintended qualities. And just as with musical instruments, any final assessment pertaining to sound quality is based on subjective criteria. This is simply a result of the different sonic characteristics of the internal components (capacitors, resistors of different compositions but of equal value, transformers, circuit layout, etc) that go into making amplifiers, pre-amplifiers, digital components, turntables, and so on. Perhaps in your view there is "perfect sound forever," but this does not ring true to my ears.

http://forum.stereophile.com/forum/showf...art=35&vc=1


Quote:
I am quite certain that a 6-foot $5 RCA wire from Radio Shack is as good as is needed, and any wire that sounds different is only making things worse.

And I'm totally certain that all replacement AC power wires are bullshit. When people believe they hear a difference they are wrong.

--Ethan

http://forum.stereophile.com/forum/showf...art=34&vc=1

Quote:

Quote:
How about it, Ethan, when did audio reach stasis?


For everything except loudspeakers (and rooms), at least 20 years ago.

--Ethan

Ethan I am proud to say you and I could not differ more in our understanding of, and approach to, audio.

Yours in music,
Ted Denney Lead Designer Synergistic Research Inc.

ethanwiner
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Re: DBT testing

Keep at it Ted, you'll get the hang of this complicated quote procedure eventually.

Buddha
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Re: DBT testing

SAS, I tend to land in your camp, but want to ax some questions...

When you are designing a piece of gear and hear the differences you hear, do you need to know the brand of, say, capacitor that you are working with in order to consistently have the same impression of its sonic attributes?

I actually do think that I have heard different capacitors have different impacts on my gear when I have tried switching them around, and I am in the 'cables can sound different group,' so I do not mean this as a 'gotcha' question.

The thing that perplexes me is that some people need to know what's on the label before they can hear differences.

Very curious!

I'd also be interested in how you think the quality of components has progressed. Tolerances seem to be much closer these days, but in Ethan's world, the last 20 years of improvements have been for naught, sonically.

Just how far off do tolerances have to be for you to notice them?

Cheers.

Frank S
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Re: DBT testing


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Keep at it Ted, you'll get the hang of this complicated quote procedure eventually.

It appears Ted likes to post in this fashion to mock his competitor. I posed a question to him on another thread that went unanswered, yet he has time to post meaningless posts elsewhere. The lack of maturity and respect displayed by some members here is completely childish. Does anyone monitor this forum?

ethanwiner
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Re: DBT testing


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Tolerances seem to be much closer these days, but in Ethan's world, the last 20 years of improvements have been for naught, sonically. Just how far off do tolerances have to be for you to notice them?


Now hold on a moment there partner! We've always had high-tolerance parts, and it's important to use them in some situations. Such as the capacitors in the left and right channels of a stereo EQ. Likewise, balanced input microphone preamps use precision resistors to reject hum and noise better. And so forth. Even 30 years ago, most 5 percent carbon film resistors measured closer to 2 percent or even tighter.

But the notion of being able to "hear" a competent (and appropriately chosen) capacitor is lunacy IMO. As you suggested, it's a helluva lot easier to identify which cap you're hearing when you can read the label.

When someone show me they can reliably identify caps blind, I'll be glad to be put out to pasture. Hell, Jan and the Frog can drive the truck!

--Ethan

ethanwiner
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Re: DBT testing


Quote:
It appears Ted likes to post in this fashion to mock his competitor.


Really? How lame. According to some here, the only mocking of competitors is done by yours truly.


Quote:
Does anyone monitor this forum?


Yes, but Stephen allows a fair amount of latitude when it comes to insults and personal attacks. As you can see!

--Ethan

Buddha
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Re: DBT testing

How about a new year's "bygones" and start from scratch?

All around?

I'm in!

ethanwiner
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Re: DBT testing


Quote:
How about a new year's "bygones" and start from scratch? All around? I'm in!


I'm in too, but I was already in a few weeks ago when Stephen told SAS and me to both cut it out. So I cut it out, but he kept at it. As you know, I never insult others first, only in defense.

--Ethan

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