John Curl's Blowtorch preamplifier part III

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Finally, after a certain forum member landed with a splash on this topic, started by debating Nyquist as "improper", then shifted the scope to an illusory ITD problem, then shifted the scope again towards the time response of ADCs (really, a filter time response issue, nothing to do with the ADC itself or its sampling frequency), then re-discovering the wheel of time limited signal spectra, nitpicking about how many cycles doeas it take for a 44.1KHz ADC to settle after a 20KHz burst, and pointing a finger to everybody else of "not being aware of the fundamentals", while the peanut gallery of Golden Ears was cheering and taking the opportunity to claim a victory over the infidels, we got to the true question in all this diversion: is anything ot these well known, well studied, amply described in any relevant literature, behaviors audible?

That is, a cymbal hit, viewed as a time limited signal, recorded through a 16/44.1KHz ADC with the associated anti-aliasing filter, can be distinguished, ears only, of course, from the same signal recorded through a 24/96KHz ADC? And what about the same in the context of music? In general, is any musical content, with whatever cymbals or other rich HF spectra instruments, digitally recorded at a high sampling rate, then decimated (that is, downsampled and filtered) to (say) 44.1KHz and 96KHz distinguishable?

To the extend that I am aware of, nobody had ever proved a positive, I myself certainly cannot, but if anybody has any relevant data to show I am all ears.
 
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I mean this YouTube He used a mic so we can hear, but I wondered if that might be a good idea anyway because it removes a variable?

That one... OK. typical micing issues of close mic'ed instruments... cant get them to sound right balance. A recording on a piano is same issue but more extream as the strings are further aprt and a larger sounding board... a close mic absolutley wont work well to cover the whole range of sounds in proper balance... an over head omni is better with the top sounding board removed . ETC ETC. He said some sounded same and some did not.

BUT, here is the rub on this. It was not a CD being played.

Basically, it was a Master and we dont know what was the recorder... analog (probably not) and if digital was it recorded at 16/44 or 24/96+

So, it does not help us much.


THx-RNMarsh
 
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@elektroj

At last I had the time to listen to your nice recordings, one 88,2/24 and the other a decimated version to 44.1/16 upsampled again to 88.2/24
I played them through JRiver with the R128 volume control switched on to prevent small level differences.
Both files where converted to 192/24 in my D/A.
Same overall setting, same hardware, same everything except these two files.

I have seriously listened to both without any prejudice and played them over and again, at least some 30 times.
To my regret I cannot hear any difference.

Thank you for having taken the trouble of preparing them.

Hans

Do you listen near field or far field? Do you have low distortion speakers? Do you listen to a Lot of live music instruments?


-RNM
 
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That is, a cymbal hit, viewed as a time limited signal, recorded through a 16/44.1KHz ADC with the associated anti-aliasing filter, can be distinguished, ears only, of course, from the same signal recorded through a 24/96KHz ADC? And what about the same in the context of music? In general, is any musical content, with whatever cymbals or other rich HF spectra instruments, digitally recorded at a high sampling rate, then decimated (that is, downsampled and filtered) to (say) 44.1KHz and 96KHz distinguishable?


Thanks for that rant which is same rant as always. Everything is just fine and sounds just like reality.

I dont know if I can or cannot hear a difference between them.... However, compared to a real cymbal next to you to compare is my critierion. Does it sound realistic to what real acoustic sounds are like. You are listening to more than a file of sampled data. I cant hear much change when I do similar tests with high distortion speakers. So, what does that prove?

Do live vs recorded. When the repo sound exactly like the live, tell me about it.


THx-RNMarsh
 
That is, a cymbal hit, viewed as a time limited signal, recorded through a 16/44.1KHz ADC with the associated anti-aliasing filter, can be distinguished, ears only, of course, from the same signal recorded through a 24/96KHz ADC?

No, it cannot. If the DBT test is performed and the digital chain incl. drivers and SW is free of some terrible basic errors.
 
Musical instruments like a piano has many characteristics to the sound depending on how that note is played.
You left out a very important aspect, where it is played.

If you do not want to accept arguments and facts that are not compatible with your hypothesis it is a bit depressing as it means that you will repeat the incorrect assertion(s) ad nauseam.

Otoh, it is always amazing to note how far people (that seem reasonable otherwise) are able to go in their denial of realitiy (means if you are interested in social sciences).
Self biography?
 
Where would you place the mic?
Close.

Some remarks. I don't (as many of my colleagues) don't agree with Ethan Winer advocating Omni-directional mics as a requisite. We all use cardioid mics, for good reasons, and close miking, for good reasons. Just they need an EQ to compensate for the proximity effect.
A the question of "where" the music was playing, the answer is "in your room".
Close miking is the only way I know to get a realistic recording of an instrument. If you want to mimic distance, reverberation has to be added. If you do long distance miking, you'll get, may-be, a correct distance feeling, but you will lose details and sound quality of the recorded instruments that your ears hear in real time. Note that, in any case, to get the right distance feeling, the mic has to be set closer than your listening position of the real event.
 
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Thanks, but I was thinking more of your system accuracy test, a voice recorded in your room and live comparison etc. The difference here being that both live and recording were recorded. Is that any more or less confounding do you think?

YOu have to do that test your self. He heard his instruments and the repo. he can tell you if it sounded the same. But it was not played off a file burned to CD in some CD player electronics. Some sounded same to him and some didnt

But, yes, that is the process, basically that i use to tell how good your system is. I suggest a voice of someone you are very familiar with... mid range. First as the recording will be at its best. then graduate to piano (if you have one) or cymbal.

He did it just as i would... onmi, close miced and you are listening to the instrument played close, too. Near field monitor for play back. yep. Same as T says, too.


THx-RNMarsh
 
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Do you listen near field or far field? Do you have low distortion speakers? Do you listen to a Lot of live music instruments?


-RNM

Just wondering, as Mr Marsh doesn't have his M2's in bangcochttp://kk so am wondering how are you doing in your present music desert in order to keep your auditory pitch in trim, do you at least have a pair of headphones to get your ears some some quality life or is the only source of hifi served at the boomboombar downstairs? Hey I'm concerned... :cool::)

Cheers
 
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