John Curl's Blowtorch preamplifier part III

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How is it possible for me to use 26 letters to reproduce 44 phonemes?

They are discrete characters in theory, but as anyone trying scanning can relate there is close to infinite variations, yet they are used to reproduce a semi time discrete tonal combination?

Which is more important, discrete time or discrete level?
 
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Badly is the usual answer
Bough/Cough
Cow/Bow
I live in Reading but if I am reading a book I pronounce it differently


And if a boat of rowers have a row over which way to row!



And Romanising Hindi words is a nightmare all of its own!


The fact that English works in any form as communication is amazing!
 
Finding it hard to believe reverb trails are being audibly truncated in a 24/196 system and you don’t have the same issue on a 16 bit systems and not be able to put it down to bad engineering.

It doesn't seem to be a problem with bit-depth. It is jitter related in the following way: if I feed ultra low jitter digital audio into the dac, I can set ASRC DPLL bandwidth arbitrarily, because it remains stable in all cases. What I find is that with minimum DPLL bandwidth the reverb tails are mostly there, but if I increase DPLL bandwidth the least amount I can, I start really losing the tails. What happens when DPLL bandwidth is low is that the VCO creates the least of its own jitter, and as bandwidth increases so does the internally created jitter.
 
Not clear that bits are being trucated exactly. Bit-depth related resolution of other sounds is still very good. I am still thinking about what could be going on. In a very speculative way I wonder if something in the S-D modulator is losing them because they are more stationary than other musical sounds. Maybe it sees them as something like drift offsets in the audio spectrum. To make that more clear, imagine a spectrogram view of music with reverb tails, where the tails can be visualized. They remain relatively stationary in the spectrum view with time according to the nature of how they sound, so knowing that maybe one could HP filter the spectrum to remove them as viewed in spectral domain. Just to be clear, I really am doing a lot of speculating at this point and probably need to do some reading to see if any of this could hold water.

Anyway, continuing with the story for now, it could be that jitter creates artifacts that causes the modulator to HP filter in the spectral domain. It does't necessarily have to be trying to go after the reverb tails directly.
 
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If you want to not get reverb tails truncated . . . Raise the noise floor.

Finding it hard to believe reverb trails are being audibly truncated in a 24/196 system and you don’t have the same issue on a 16 bit systems and not be able to put it down to bad engineering.

Which in any recorded 24 bit depth recording you have at best approximately 3 bits of noise. (under the glaring assumption that the levels are set to use most of the dynamic range) You may well have greater noise floor from Brownian motion of gas molecules impinging on the microphone.

This whole thing, in general, isn't adding up to what I remember learning along the way. As I said though this isn't my domain of expertise, so I fully reserve the right to be wrong.

Bill, unless there's something hideously wrong, the filter curves I've seen from ti/akm/cirrus(Wolfson) all are benign, and would leave me doubting anyone could hear the difference. Exception being perhaps different folks's slow roll off implementation on 44.1 or 48 where both hf rolloff and aliasing are potential concerns. There's a simple solution to that one, though: don't use those filters!
 
There are three low cost tweaks that will improve almost any sound system.

First is the application every full moon of DeOxit contact cleaner.
Amazon.com: DeoxIT Contact Cleaner and Rejuvenator Bottle with Brush Applicator, 7.4 ml: Industrial & Scientific Both measures and sounds better. However it does not work instantly so if you want to do a test just apply it to all the connectors for one channel.

The second item that has been one of my secrets for large scale installations is foam tape that to remove you pull it from the side and it comes off cleanly. This is placed everywhere! The bottom of any furniture feet, loudspeakers, equipment feet etc. On any large panel that vibrates (think top of CD player etc.) an X will do and you leave on the non-stick film where it is open air. That way you don't use it as fly paper. The idea is anyplace two surfaces contact place the tape. Any large panels that can vibrate including windows if you can. This eliminates vibration absorption of specific frequencies, extended resonances of other frequencies and most importantly buzzes.

The third one is free. Every season change, take your loudspeaker cables and swap the loudspeaker and amplifier end. Treat it with DeOxit if you have it. (This really works and not for the silly reason some folks come up with.)

SNAP! (well, to #1&2) the oxidization inherent to all contact systems especially those with nickel needs to be burnished and the "preservative" oil in DeOxit seals oxygen from the burnished contact pair. I also agree with the DeOxit for #3. Can you do more than tease us regarding the end-to-end suggestion?

Cheers,
Howie
 
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Howie: I have my bottle of deoxit, but every full moon is too much. It did fix up a tv remote once where one of the buttons had stopped working.



Daniel: I was meaning more the time domain response of the digital reconstruction filter. Take for example Chord Electronics Qutest D/A processor Measurements | Stereophile.com where chord offer you 'Incisive Neutral' or 'Warm' Filters with different time domain responses. In their case roll off is extremely sharp so no aliasing. But they will not produce exactly the same output. I see this as as likely to be audible has hash 120dB down.
 
Daniel: I was meaning more the time domain response of the digital reconstruction filter. Take for example Chord Electronics Qutest D/A processor Measurements | Stereophile.com where chord offer you 'Incisive Neutral' or 'Warm' Filters with different time domain responses. In their case roll off is extremely sharp so no aliasing. But they will not produce exactly the same output. I see this as as likely to be audible has hash 120dB down.

Okay, yes we're talking the same thing in different mindsets. And I agree with the assessment, but that will not stop people from casually mentioning a huge difference. ;)
 
Howie: I have my bottle of deoxit, but every full moon is too much...

Hey Bill,
I agree; I thought Ed said once per blue moon, once again I am guilty of not reading carefully. I typically burnish/preserver patch cables once per year or two which works well for me. If one lives in a humid and corrosive atmosphere like a seaside home, more frequent may be warranted.

Howie
 
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