John Curl's Blowtorch preamplifier part II

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I'm no expert but my new DAC is definitely an improvement over my old one.
Oh, there is a lot of way to even improve the same DAC. Low noise digital reference and rail voltages, clean analog rails, better clocks ... all the analog stages....
How to transform a cheap Behringer DCX2496 from a pretty bad sounding device to a very impressive and transparent machine. Day and night.
 
And that is most likely single mode with decent connectors. Toslink is nasty plastic fibre with nasty inaccurate connectors and nasty multimode. It can't possibly sound good. At least that is way some paint it. Like I say need to look for any measured data comparing the 2.

wave division multiplexed fibre setups are impressive beasties when you are plonking 64 high througput frequencies down a 9 micron diameter glass tube. Then half the bandwidth is wasted using MPLS. Sob.

one I worked on had 105 x 10Gb channels down each fibre.
 
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I'll have to test it to see if they do or how good/bad they do in my player before I believe it applies to my unit.

Richard
They do. Every CD player does.
In your Sony DVP-CX985V this functional block is hosted in IC301, an 176 pin DSP processor. The RAM (16Mbit D-RAM) is IC 303.

You can’t check how good/bad they do it but if you are still in doubt that such an operation is taking place, monitor DSP chip’s pin 29 ("Write enable signal output to the D-RAM")


Something more useful. This is the Digital out of your Sony DVP-CX985V

George
 

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As long as you are in the digital domain, there is no "Kind of sound". Just datas, with errors or not. And you can compare it objectively comparing them. No room for poetry. As said Scott, any error, executing a program at GHz in your computer can, most of the time, lead to a blue screen. Is-it so often ?

I don't think bit perfection was ever in question here, the slight frequency response errors due to very slight clock frequency deviations are interesting.
 
Increased jitter seems a common complaint with toslink. Thats what i put down to the more sterile sound i got using it but the usb-spdif converter and the dac i used at the time cost a bit less than $500 in total. Things move fast in this area though and what your currently using is often outdated as soon as you bring it home.
 
The "more sterile sound" is a common complaint, equals digital reproduction misbehaviour - nicely equivalent to vinyl "roar", and pops and crackles ... and "jitter" has become the grab bag term for the cause of this - which may or may not be the case in a particular instant. Putting out money for a shiny new component, or technology, more sparkly than the one you had before, may "solve the problem" - then again, it may not - toss of the dice type of thing.

A more sensible approach is trying some experiments, to try and isolate what the causes of the lesser sound are, and progress from there ...
 
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The "more sterile sound" is a common complaint, equals digital reproduction misbehaviour - nicely equivalent to vinyl "roar", and pops and crackles ... and "jitter" has become the grab bag term for the cause of this - which may or may not be the case in a particular instant. Putting out money for a shiny new component, or technology, more sparkly than the one you had before, may "solve the problem" - then again, it may not - toss of the dice type of thing.

A more sensible approach is trying some experiments, to try and isolate what the causes of the lesser sound are, and progress from there ...

Thats what i did within the limitations of my knowledge of these things, after a couple of weeks using toslink i went back to my old fashioned coax connection, it was definitely better and reading up on it, increased jitter seemed the most lightly culprit. The new DAC i bought is streets ahead though, i've never heard my system sound so good, it still stuns me when playing favorites of old, just how much information was being missed. I can now make out words in some tracks that i have never been able to identify before. Musicality (is that even a word) is far better as is overall enjoyment so i reckon i'm heading in the right direction. My significant other (not an audiophile) :D even lets me play it louder than before.
 
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OK have done some research and does appear that modern equipment has identical jitter performance on either link. I didn't have an external DAC until 3 years ago so had not paid too much attention to the measurements. But on inspection of real test data it would seem I had allowed 1990s hifi press saying 'Toslink is rubbish' to set a bias.

I've stopped reading those magazines now so am getting better :)
 
The new DAC i bought is streets ahead though, i've never heard my system sound so good, it still stuns me when playing favorites of old, just how much information was being missed. I can now make out words in some tracks that i have never been able to identify before. Musicality (is that even a word) is far better as is overall enjoyment so i reckon i'm heading in the right direction. My significant other (not an audiophile) :D even lets me play it louder than before.
All "sounding" good then :) ... people with a hangup about 16 bits not being enough just do ... not ... get ... it - the amount of sound - in all senses of that term - information on even the "crappiest" of recordings is quite staggering, most people would barely be registering, ouhh, 20% of what's there, :D.

A good basic approach is to always look for getting more information from the CD - the right direction - which may be accompanied by edginess, "unpleasantness" - an issue. The latter is a distortion artifact, and can then be resolved by the next step in optimising.

To give an example, mentioned recently, :p - Relax, by Frankie Goes ..., etc. Excellent material to work with - there is a water splashing sound in the mix - and the trick would be able to lift that particular element more and more out of the mix, so it stands completely separate from the rest of the sounds, with complete integrity in itself - it lives in its own acoustic, and can be easily "seen" by your hearing to be a distinct part of the picture - just like tuning into the voice of one person talking, along with others, in a room. Once the separation occurs cleanly, then one needs to be able to play that track at any volume level, right up to a reasonable maximum, with no loss of integrity of that splashing sound.
 
OK have done some research and does appear that modern equipment has identical jitter performance on either link. I didn't have an external DAC until 3 years ago so had not paid too much attention to the measurements. But on inspection of real test data it would seem I had allowed 1990s hifi press saying 'Toslink is rubbish' to set a bias.

I've stopped reading those magazines now so am getting better :)

According to this article :) it depends on buffer size, apparently? toslink has a slower rise time. As with everything audio, opinions vary :D

The Well-Tempered Computer
 
To give an example, mentioned recently, :p - Relax, by Frankie Goes ..., etc. Excellent material to work with - there is a water splashing sound in the mix - and the trick would be able to lift that particular element more and more out of the mix, so it stands completely separate from the rest of the sounds, with complete integrity in itself - it lives in its own acoustic, and can be easily "seen" by your hearing to be a distinct part of the picture - just like tuning into the voice of one person talking, along with others, in a room. Once the separation occurs cleanly, then one needs to be able to play that track at any volume level, right up to a reasonable maximum, with no loss of integrity of that splashing sound.

I get on just fine with 16 bit, done well it can be stunning.

I remember when they banned that Frankie video here and the reason given, splashing was definitely part of it but it's not my area of - well -(expertise) for want of a better term :D
 
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