CD Transport Experience

[carlosfm]

Re: Re: Re: Re: CD Transport Experience

Never claimed to play SACD data. Go to dcsltd.co.uk to find out about the 972/954 which upsamples and plays CD in 24/192 or DSD format using either twin 110R for PCM or SDIF2 3 75R cable for DSD.

I was stressing the importance of factors in CD transports other than jitter or interface. A8 seems to concur.

I heard the DCS SACD transport, Upsampler and Dac playing, connected to the Halcros (pre and power amps) and B&W 800 Signature speakers.

What confused me is are you using the two SACD players to pass 44.1 data?
Then you transform that 44.1 into 24/192 or DSD.
I'm not surprized that the DSD conversion sounds inferior to you.
It's easier to upsample in PCM, but even then it doesn't make the wonders some people say.
If you have very differend results using the two SACD players as transport, then ok, you're right, there's something there.
But my god, you're not supposed to connect a 670 SACD player to a DCS.
I bet that the digital cable of the DCS costs more than the 670 SACD player.

 

[tiroth]

An ASRC can not remove jitter from the source completely

Certainly true, but let's use AD1896 as an example. The servo loop rejection starts at 2Hz and is 100dB down at 1kHz. That is quite good.

and adds a lot of jitter too.

I don't understand this. Again, a concrete example (AD1896) shows some spurious response close in to the test single that could be jitter sidebands. None are higher than -150dB in level for inputs from 1-20kHz.

It can sound ok in an external DAC, but is certainly not the best available (theoretical) method for jitter reduction. A DAC equipped with ASRC will still be sensitive for different transports, digital out mods and the CD(-R) quality.

I certainly haven't made up my mind on this, but jitter immunity is a worthy goal and I think it is at least possible that ASRC is the answer. Now, ASRC may well cause other problems with the sound, but I doubt they are the result of injecting jitter.

Anyone have a good way to purposefully "inject" (cause) controlled amounts of jitter in a transmission line? If we want to do more than stab in the dark we really need a way to test how much dependence a DAC has on clock jitter. I've thought of bandwidth limiting the tranmission line, but I think the amount of jitter will be very hard to "dial in", not to mention how difficult it is to make absolute jitter measurements.

 

[fmak]

Re: Re: Re: Re: Re: CD Transport Experience

What confused me is are you using the two SACD players to pass 44.1 data?
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Why not, I was comparing 24/192, DSD upsampled from the CD layer with SACD thru the 670 and 777 with matched gain. What I have found is that upsamped CD is much better than 44.1/16 playback and in many ways comparable to SACD on the 777. But, of course, the dCS is a much better dac.

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If you have very differend results using the two SACD players as transport, then ok, you're right, there's something there.
But my god, you're not supposed to connect a 670 SACD player to a DCS.
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What I wanted to highlight was that a tweaked CD output on the 670 with Tent XO3 and careful interfacing was no match from the untweaked (except for connector) 777. There are factors other than the clock or interface jitter as Guido and A8 have pointed out. Note alos that there are some contributors here and elsewhere who assume that the clock on the 777 is rubbish and that it must be replaced.

 

[carlosfm]

Re: Re: Re: Re: Re: Re: CD Transport Experience

What I wanted to highlight was that a tweaked CD output on the 670 with Tent XO3 and careful interfacing was no match from the untweaked (except for connector) 777. There are factors other than the clock or interface jitter as Guido and A8 have pointed out. Note alos that there are some contributors here and elsewhere who assume that the clock on the 777 is rubbish and that it must be replaced.

The transport makes difference.
The stability (less work for the error correction chip), the laser lens (glass in top Sonys and plastic on the cheap and not so cheap ones), components, PSU, sometimes a better circuit layout, etc.
It seams natural to me that you can't get to the performance as a transport of the 777, even tweaking the 670.
There are things you can't change, as the transport.
You might get near, though.
But if you tweak the 777...

 

[Fin]

Hi all

I am trying to get a discussion going on a subjest closely related to this one, but fucussing on the problems caused by servo's.

If anyone is interested, it is located here:-
Jitter induced bt servo's

The jitter (even the pit jitter) at the RF is very important. It all starts there. Depending on concept and implementation and quality of (re)clock circuitry (and rest of driove, induced jitter by servo's is a known one....), a certain jitter will remain at the SPDIF output or DAC chips.

That is what you actually listen to....

 

[Fin]

Servo section power supply

Is it worthwhile providing the +/-10V servo section with a separate transformer/powersupply and regulator?

If so, what would the requirements be for smoothing capacitors and regulators etc?

 

[smithie]

teac p500 transport


hi guys, ive just joined this forum so bare with me till i adjust...and take this chance to say hi to everyone!
after reading alot of stuff on here about the joys of teacs vrds mech,i got buzzing and decided i needed one of those(to excitable),anyway long story short is on e-bay i won a teac p500!
now i need to know,is what i brought any good in the teac world of transports.? cant find any info on this player anywhere,if anyone has some material,reviews,sites etc and anything else i would be grateful,also what teac version transport is inside this unit.
brought it has i would like to build a dac to go with it and all the various mods that people can surgest that will help me get the max out of it.
if it isnt as good as the 10.7.1 transport then please tell me now and ill sell it on and try to locate the teac model surgested
im a empty vessel waiting to be filled,so in advance i say thanks for any help.
all the best
smithie