John Curl's Blowtorch preamplifier part III

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DAC interchannel time shift is easily measurable by a two channel scope. Old soundcards had issues. But you were speaking about sub-microsecond shift audibility when known literature speaks about 2 us threshold limit. What is your source? "Been there" is no answer.
Sub microsecond shift audibility is not a question. As in, I never stated such.
What I did say, was that to measure a delay at the one or two microsecond level, it is important to design a test method which can measure at the 200 to 500 nSec level.

You presented a test of a cable and load which by design would settle in half a microsecond, used a 3 uSec settling drive waveform, and claimed no joy.

It is important you read posts more accurately in this case.

Jn
 
Except for insulting everybody’s intelligence and basic common sense. Happens that “close minded” rely on intelligence and common sense.

Intelligence does not increase the probably of being correct outside of one's area of expertise. People who are intelligent are better than other people at thinking up long lists of all the reasons they are right, even when they are wrong. It means intelligent people can be more stubborn than normal people since they more clever at reinforcing confirmation bias and overconfidence bias.
 
The entire audio chain is comprised of some very complicated stuff. Electronics which many here are excellent at, speakers...same deal, sources, testing, etc.

But there is a disconnect. A virtual soundstage requires more than just low distortion electronics. It is important to understand what compromises the virtual image.
Without understanding what is needed how does one control it?
Over the years I've tested the stability of both lateralization as well as localization on myself only. And in that process I've had to do a lot of research.

We have quite a few here that are very knowledgeable in human hearing capabilities, it is important that all discuss.
Jn
The first thing is to control system noise and LR noise coherence is critical.
My putty accomplishes this with result of much improved localisation and positioning of sound sources within 3D sound field.


Dan.
 
Intelligence does not increase the probably of being correct outside of one's area of expertise. People who are intelligent are better than other people at thinking up long lists of all the reasons they are right, even when they are wrong. It means intelligent people can be more stubborn than normal people since they more clever at reinforcing confirmation bias and overconfidence bias.

What immediately follows from this statement is that idiots are more prone to be “open minded”.
 
That could be. So are intelligent people who are smart enough to know that thinking up reasons they are right can be pretty stupid if they don't know the subject matter well.

What about idiots that don’t even know what they don’t know, but love to consider themselves experts? In the high end audio world I would call these “open minded useful idiots”. Otherwise, for other areas, the last word would suffice.
 
Of course it is obvious that any toxic compound must damage sound.
Now here is an interesting test: find a compound which is toxic to one species but not to another and see how it affects the sound for each species when included in the insulator for a cable. You might not be able to get cats or dogs to do an ABX test, but I'm sure something can be done as their response to sound can sometimes be seen.
I've run the relevant experiments long time ago on myself so no need to study animals, that would be cruel.

Dan.
 
So, a rather technical discussion of localization.....and now your putty suddenly fixes it.
Wow, what a coincidence.
I have said it before, same information about much better LR/depth imaging. It seems to come down to dynamic system noise affecting perceived timing of peaks or something like that and thus affecting localisation precision.

The curious part is our sensitivity to what ought to be next to nothing....or maybe not. -40dB noise riding on top of a sinewave will shift the peaks around in amplitude and time....maths anybody ? Music would be more sensitive to peaks shifting, the nature of noise/errors would be further spectrally sensitive.
Forcing LR coherence of system intrinsic noise improves phantom image LR positioning and width and precision of image depth and image depth positioning is what I find.

Dan
 
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Of course it is obvious that any toxic compound must damage sound.

Now here is an interesting test: find a compound which is toxic to one species but not to another and see how it affects the sound for each species when included in the insulator for a cable. You might not be able to get cats or dogs to do an ABX test, but I'm sure something can be done as their response to sound can sometimes be seen.

Chocolate placed on my speakers gives a coloration to the sound that really agitates dogs.
 
Max,

Quit giving me straight lines.

I can think of many sound systems where a bit of putty will greatly improve things.

In large quantities applied to the driver cones. Of course even a small bit will provide dramatic improvement for some systems when carefully placed in ones own ear canals!

So obviously useless to argue about such when common experience and a bit of sense will yield that putty will have an effect with certain uses.
 
Yes. At first, headphones...I was really having a problem with imaging. Turned out the sound card was sharing a DAC with a pair of S/H. Image was off center, and panning it back to center produced really weird image problems.

This the measured example how the "normal" sound card D/A behaves. DAC (96kHz) is driven by a stereo single impulse in both channels, the signal is a 10s silence with 1 impulse occurring at 4s time simultaneously in both channels. The scope is set to 25MHz sampling (one sample per 40ns). Trigger is one shot. The scope record shows impulse response of 2 DAC channels and no time shift between them. I agree that it is good to check the sound card or the DAC this way, but with the contemporary DACs this is a non-issue. 15 years ago or so it might have been a problem of cheap sound cards, however usually the one sample shift occurred at the A/D side.
 

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