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Discussion Starter · #1 ·
Okay, so a search through the forums seems to turn up a bunch of confusing stuff concerning digital distortion or something. Here's the general premises of what's going on.


I just got a set of B&W CM8 Speakers powered by the Rotel Stereo Pre-amp and amp (RC-1580 and RB-1552 respectively). The pre-amp only takes analogue inputs (via RCA) so the Rotel solution would be to use their CD player ($999) which contains an internal Wolfson DAC. I personally wasn't too keen on using the Rotel CD player mostly because it's a $999 box that only plays CDs. You can't even use the internal DAC independently because there isn't a digital input. So I figured I would get a DAC (leaning towards the Arcam rDAC, any suggestions there?) and connect an old cheap DVD player via Co-axial cables.


I assume that there shouldn't be any loss in signal quality due to the not-so-great DVD player because it is just reading and outputting digital signals. Since the rDAC is doing the heavy lifting of converting the signal, I should still be able to get the same quality if I had gotten the CD player right?


The other advantage of getting the DAC other than saving $500 is the possibility of expansion. I do plan on ripping my CDs loselessly soon and streaming it off a computer. By having a dedicated DAC, this should be pretty easy via USB or Toslink.


Thanks in advance for the input!


Equipment (Sorry, won't let me post links)


DVD Player : APEX AD-660 (Co-Ax Out)

Also have a Pioneer DV-525 with Co-ax and Optical Toslink (Both aren't being used so either one could work)


DAC : Arcam rDac


Preamp : Rotel RC-1580


Amp: Rotel RB-1552


Speakers : Bower&Wilkins CM8
 

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Digital audio as on a CD is PCM (Pulse Code Modulation).

To play it you have the samples (the bits) and the sample rate.

Perfect PCM audio is feeding the right bits at the right time into a DAC.

The timing is a matter of a clock.

Clocks will always have a small deviation in their cycle to cycle time.

A transport sending bits to a DAC will always generate some kind of input jitter (small fluctuations in timing).

By design PCM audio is bits + timing, both must be right.


The confusion starts the moment practice comes in.

- What is the audible threshold of jitter?

- Is the amount of jitter generated by the transport above this level?

- To what extend can the DAC reduce input jitter?

- Is your gear revealing enough to make this audible?

- Etc.


I think a lot of today's well designed consumer gear already has such a high technical standard that it is hard to get a substantial improvement.

Your DVD player might turn out to be a good performer.

http://thewelltemperedcomputer.com/K...fectJitter.htm


rDac, one of the new generation featuring Asynchronous USB.

This is what many think the right way to eliminate input jitter.
http://thewelltemperedcomputer.com/HW/USB_DAC.htm
 

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Quote:
Originally Posted by Roseval /forum/post/19556527


Digital audio as on a CD is PCM (Pulse Code Modulation).

To play it you have the samples (the bits) and the sample rate.

Perfect PCM audio is feeding the right bits at the right time into a DAC.

The timing is a matter of a clock.

Clocks will always have a small deviation in their cycle to cycle time.

A transport sending bits to a DAC will always generate some kind of input jitter (small fluctuations in timing).

By design PCM audio is bits + timing, both must be right.


The confusion starts the moment practice comes in.

- What is the audible threshold of jitter?

- Is the amount of jitter generated by the transport above this level?

- To what extend can the DAC reduce input jitter?

- Is your gear revealing enough to make this audible?

- Etc.


I think a lot of today's well designed consumer gear already has such a high technical standard that it is hard to get a substantial improvement.

Your DVD player might turn out to be a good performer.

http://thewelltemperedcomputer.com/K...fectJitter.htm


rDac, one of the new generation featuring Asynchronous USB.

This is what many think the right way to eliminate input jitter.
http://thewelltemperedcomputer.com/HW/USB_DAC.htm


+1


Nice refs. Nice site.


Only 21 posts in 2.5 years; you should post more often.


Any chance that you are the main person doing the referenced site?



Cheers
 
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