John Curl's Blowtorch preamplifier part II

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Sorry for repeating my query, as I have already asked the same question in different thread. I am looking for 'old' reviews on sound quality compared to Cassettes/Vinyls when CDs came out (Probably in 80s I think) As the medium was new I am trying to compare reviews than and now and find some similarities; both positive and negative.
Thanks and Regards

Bad idea, it took several years for engineers to fully adopt dither and it is not hard to find early CD's with bad MSB transitions to boot. This was all discussed in several AES papers.

I have an original CD test disk from SONY/Dennon (1984?) that was not dithered. Another amusing thing is the current preferred low cost "premium" DAC solution will clip on several test tracks that hit digital full scale.

Re: 440/442 etc., I posted a while back that at least one expensive external DAC was .6% fast at 44100 due to an error in the clock generation, could find no reference anywhere that anyone ever noticed.
 
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I have an original CD test disk from SONY/Dennon (1984?) that was not dithered. Another amusing thing is the current preferred low cost "premium" DAC solution will clip on several test tracks that hit digital full scale.
What does that mean....that the DAC hits max output some LSB's below digital full scale ?.
Which particular DAC are you talking about ?.

Re: 440/442 etc., I posted a while back that at least one expensive external DAC was .6% fast at 44100 due to an error in the clock generation, could find no reference anywhere that anyone ever noticed.
How did that happen ?.

Dan.
 
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What does that mean....that the DAC hits max output some LSB's below digital full scale ?.
Which particular DAC are you talking about ?.


How did that happen ?.

Dan.

Yes the "SOTA" DAC clips somewhere around 32000 rather than 32767. To be fair it could be the implementation, I can't find the product now, it was a optical/coax multisource switch with DAC.

In the end I took an Aglient frequency standard and counter and confirmed that they matched to 7 or 8 digits, recorded 1000.000kHz at 44.1 and 96k when played back the first was 1006.xxx and the second was 1000.000kHz.
 
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Jan how is that, yes to one and then ditch it the sentence after, are you schizophrenic..??

Natural is what you are used to, what you have accepted as 'as it should be' for many years.
Anything else sounds 'unnatural', even if it is objectively more accurate to a source.

That is one factor that played a role when CD was introduced. Vinyl was considered 'natural' because that's what had been come to be considered as 'natural'.
CD was thought to be 'unnatural clean, clinical, cold, etc' because that's what it was perceived with respect to the 'standard' vinyl.
But CD was/is clearly more accurate in reproducing the original source.

Jan
 
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Wow, I've never seen a player do that, not even the odd portable I've tried.

Never looked at that really, but I did look at the signal on CDs. Same thing, hard clipped more often than not, right there on the shiny disc. And then we expect out super-duper DAC to save us ;)

BTW The 2nd pic is interesting as it shows the original on the CD clipped, and that carried over to the vinyl version!
Quizz: why does the clipped portion on the vinyl droop upwards?

Jan
 

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Acurate as a source and looked at isolated, but you can't look at a system isolated, the system needs an interface between the recording and the listener, if vinyl fits the system better then it's the better source, who wants something that sounds unnatural...?
I admit that the weak point here is the dynamic speaker driver, but that is what we have for now and in the foreseeable future. This is clearly part of what is lost, how to claw that naturalness back in the music reproduction I don't know.
But I see thes as key to the decline HiFi has seen. The decline of joy and goosebumps to something those who fail to listen claim is better. Music is about emotion, nobody will love it if it does not excite an give you joy. Tremendous work ahead of us all.
 
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The decline of joy and goosebumps to something those who fail to listen claim is better.

An anecdote take it or leave it. I was in Walt Jung's basement listening to his prototype of the AD815/AD823 line stage IIRC. He put on Mahler, and I can't remember exactly the piece/movement, he stopped the music and asked me if my lower back just involuntarily tightened up. I said, well yes, and he laughed telling me that that emotional reaction at that point meant "everything is right" or words to that effect. I joked that we did share very similar cultural genes after all (shades of Dr. Strangelove). :) (Please take this in a spirit of amusement).
 
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