What causes grainy sound

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#301
Bill Coltrane said:
Some people just think they can't fool themselves.
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On that, I agree with you completely.

However, I would not agree that everyone reporting effects you have not personally perceived deserves to be thrown in the bin of people who are fooling themselves.

You might be fooling yourself if you think cables, materials, etc., can never have audible effects. Of course, you might think you can't fool yourself, but hopefully you know you can just like I know I can fool myself sometimes too.

In my case, I ask other people to describe what they hear if anything. If they hear differently than I do (not just in terms of preference, but in the details), then I know I have a problem to resolve.

In other words, fooling oneself is a practical problem that requires practical methods to overcome and or compensate for.

Test instruments are nice to use too, but very expensive for what I would need/want to measure. Can't afford $50k just for a scope, not happening.

mountainman bob said:
Are there ways to measure prat vs freq response real time?
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You can measure frequency and phase at the same time, an FFT does that although phase information is often not displayed.

However, you cannot directly measure PRAT since it is a perceptual term, not a physical term. You would first have to figure out what it takes to produce PRAT: how many dimensions are necessary to describe its physical attributes, and how to measure each one.
 
#303
Markw4 said:
Of course, when things are audible, then they are also measurable, not that they necessarily show up in an easy-to-measure fixed level 1kHz FFT, but they might.
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The most important sound perception that i know of, cannot be measured by that method.

Markw4 said:
However, you cannot directly measure PRAT since it is a perceptual term, not a physical term.
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I disagree. 🙂

edit: i didn't see the word 'directly'. actually bob was aware what it is comprised of.
 
#304
johnego,
we mostly see examples of bad circuits. Jean Hiraga did not use voltage followers to drive the output transistors. For instance, genuine VFETs have an even lower transconductance, therefore are more in need of a forceful driver. At the same time, VFETs constitute a heavier load than LFETs so there is a risk of excessive saturation in the driver transistor.

It is not possible to concisely explain the voluminous problems associated with balanced topologies. But I can assure you that it is a depressing reading.
 
#305
johnego said:
There are things (claimed to be) audible that have not been proven. Like the resistor's sound. How are you going to prove that they are indeed audible? You are then pushed to conclude that either (1) those are liars (2) you don't understand. Many prefer option (1).
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What would help your post to be more credible is to back up the claims with evidence.
Markw4 said:
Wait a minute, please.

In light of what is now known about human perceptual testing, I'm not convinced it has ever been done properly in audio (nor in some cases outside of audio).

Maybe DPH will want to chime in with his views, if he happens to be reading along.

One problem is that publications never include enough information to allow accurate replication of the experiment. Standards for human testing have evolved to include a requirement independent replication.

In addition, the number of test subjects required for acceptable statistics keeps going up, and Effect Size also needs to included in study results.

Unless engineers who want to do human perceptual testing recruit experts in such testing as research collaborators, it is unlikely any testing they perform will actually be conducted properly.
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Your posts resemble more and more like those of audio business posters. You've recently stated that you are not in audio business. Perhaps you are about to start one or just started. :scratch2:
Markw4 said:
Unfortunately, sometimes things we don't normally expect to be audible are found to audible in certain circumstances. Of course, when things are audible, then they are also measurable, not that they necessarily show up in an easy-to-measure fixed level 1kHz FFT, but they might.
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No example to cite?
Markw4 said:
I didn't say I can't find publications. I say they are not credible, particularly when it comes to people who spend a lot of time designing amplifiers and listen very carefully for the effects of any change. Practice matters a whole lot in how brains recognize patterns in sound waves.
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What good does subjectively very careful listening do? Nothing when it comes to obtaining objective data.
scottjoplin said:
You might just be fooling yourself, unless you have a fool proof method to test that, but only a fool would consider his method to be fool proof.
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:up:
 
#306
Dc coupled SS outputs are a huge compromise... for anyone who studied circuits seriously.

Now, a scope is cheap, you can have a digital scope for under 1k and some surplus from the government for same price.

I have 192kpbs/24 bit spectrum samplers and they do not snow what the ear can find.

The scope shows that amplifiers cannot track easily an arbitrary waveform. There are also websites where you can set up your own test signals with multiple waveforms at signals and intensity. It is surprising how bad a loudspeaker is...

Even if you had a scope, you could hear differences that are not captured in a intelligible fashion by a machine. On the positive side, I have been able to confirm a reduction in harmonics in THD samples of all my better sounding designs, so the sun is still shinning and you can still confirm audible improvements with very accurate THD spectrum samples.
 
#308
Markw4 said:
I didn't say I can't find publications. I say they are not credible, particularly when it comes to people who spend a lot of time designing amplifiers and listen very carefully for the effects of any change. Practice matters a whole lot in how brains recognize patterns in sound waves.

In any case, most published medical research is false, as it turns out. And researching hearing ability is medical research. The work of John Ioannidis is taken very seriously in that area:
John P.A. Ioannidis' Profile | Stanford Profiles
John Ioannidis - Wikipedia

For example:
Why Most Published Research Findings Are False
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Yes everything in science is wrong...
 
#312
gabdx,
you are not able to explain this, but it does not matter. You are still right.

picowallspeaker,
it's not a question of what exists cognitively but physically. Ecco.

analog_sa,
without awaiting any answer, remove the parts constituting the harmful balanced circuits in the preamplifier and give them to charity. You disappoint me.
 
#313
Markw4 said:
However, you cannot directly measure PRAT since it is a perceptual term, not a physical term. You would first have to figure out what it takes to produce PRAT: how many dimensions are necessary to describe its physical attributes, and how to measure each one.
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Exactly 😎

Y’all keep saying if you can hear it......it can be measured.
I don’t think it’s all psychoacoustics, think some people are just more sensitive in perception than others..........aka 5%’ers 😛
 
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#317
Yes, his research culminated in the design of his speakers, which he considered "good enough", Linkwitz said a similar thing about his speakers. One then has to ask oneself when people on forums poo-poo the notion of "good enough" what is their point, and if they really have one why don't they do something about it like Geddes and Linkwitz have?
 
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