[ted_b]

I am very interested Dan.  This low jitter S/PDIF (or AES/EBU) approach is the right one.  Couple that with your great tube analog stage expertise and we have a winner!!

I've been demoing 12+ DACs over the past year, and one thing is quite clear......it's about the implementation!!  Pay attention to the little things and the big things (like version of actaul DAC chip) seem less important.

[modwright]

Thanks for that.  You can buy spare laser mechanisms at Sony Parts and Accessories.  They don't cost much and if you are concerned, not a bad idea to buy one and put it in the closet.  Sony has always been very good about offering parts for service however, for at least five years after the unit is discontinued, which the XA-5400ES has not.

I have not had a single failed laser in a XA-5400ES, but over time, all CDP's will require a new laser.

Thanks!

Dan

[modwright]

Hi Ted and thanks for stating what I have held to be true for quite some time. "version of actual DAC chip seems less important".  Don't get me wrong, you need to use a good chip.  However, there are great chips from Burr Brown, AKM, Wolfsen and ESS SABRE that all sound great.

BUT, if you have excessive jitter and couple to an inferior analog stage, the sound will NOT be good.  I would expect the DAC that has the poorest specs on a list of DACs, with correct clocking implementation and a good analog stage will EASILY outperform the superior DACs.

When we finalize the design for our own DAC, I will choose the DAC chip carefully as well!  But, everything matters and I do believe that too much importance is placed on the actual DAC chip, without an understanding of the REST of the circuitry that is needed to make the end product perform at its best.

Obviously, adding a digital input to the Sony or Oppo players allows the use of their DACs, which are Burr Brown and ESS SABRE, respectively.  Both excellent DACs.  The mofied units have our tube analog stage which is also exceptional, with a very sophisticated tube-rectified and dual-discrete SS voltage regulation circuit.  If we are to add a digital input to the player then, the key is HOW the data is interfaced to the DAC, in such a way that jitter is minimized, all other things being equal.  This is why I REALLY WANT to pursue the option with a proprietary and sophisticated clocking system - beyond that of a simply crystal oscillator with voltage amplifier - that includes buffering and algorithms that produce the absolute lowest jitter I2S digital signal (native data format) to the DAC.

I am about the pull the trigger here, but I need to know that there is sufficient interest, as the standard method of using a simple input receiver with crystal will be good, but not GREAT.  I want this solution to be GREAT.

This digital input and clocking circuit will also be used then, in the DAC that we design for our standalone product in the future.

Sincerely,

Dan W.

[klao]

I had a Cambridge 840C before and its DAC + digital input was a nice touch.  Late next year I'll explore more into digital files playback, so I'm interested with your idea.  (Don't wanna find another rack space and extra power cord for an external DAC.)

I was seriously eyeing the BDP-83SE Tube Mod of yours, but since the BDP-95 is coming along, I'll have to wait for your mod & internal DAC in that newer Oppo.   

[modwright]

As soon as I have the option to evaluate a BDP-95, I will post my findings.  I am not sure if they are available yet.

To be clear, this upgrade does not include ADDING a DAC to the player, but rather, using the players own DAC to feed external digital sources, such as high-rez files.

Thanks,

Dan W.

[woodsyi]

There is interest here.  Dream to be GREAT, Dan.  If you build it, people will buy.  One thing constant through the years has been excellent sound you have achieved.  If you build a GREAT DAC, people will buy -- even in Iowa. 

[modwright]

Thank you for that! I believe I WILL proceed with this.  I appreciate your support!

Sincerely,

Dan

[Phil]

This kind of setup is so versatile and a great way to try computer-based audio. 

I have a similar setup (universal with SPDIF input).  My wife uses the CDP's transport and I use the Logitech Touch.  I'm interested in what you find with your modified units, Dan.  My own experiments surprised me:  the humble stock Touch ($300) is more musical than the universal's own transport.   

Good luck with the new technology!

Phil

[modwright]

Thanks!  I like the touch also, for its extreme versatility.  On its own, it is good, but not 'High-End'.  I have not used it as a transport only yet, but that WAS my intent when purchasing it.

Take care,

Dan

[modwright]

Redirecting this thread to a new post with final design information and a more exact and pointed title:


http://www.audiocircle.com/index.php?topic=89297.msg879210#msg879210

[klao]

Around Feb 2011, they said. 

http://www.oppodigital.com/blu-ray-bdp-95/

As soon as I have the option to evaluate a BDP-95, I will post my findings.  I am not sure if they are available yet.

[modwright]

Oppo says that it will  not be available for another couple of months?

I don't think that we will be pursuing the 93.

Thanks,

Dan