ESS Sabre Reference DAC (8-channel)

[MrMajestic]

Just got myself a Denon DVD-1920 off of ebay Would it be beneficial to use a TP SPDIF receiver inside it to transfer PCM audio to the outside? I remember this being done on the Oppo. Also, I might be wrong on this, I remember Russ or Brian talking about a board to be designed for use with the Denon to get DSD to the DAC. Is this something that is being done, or was I dreaming

[MrMajestic]

Originally posted by Russ White


I am planning on producing an SDIF3 DSD output board at some point yes.

I would not bother with using the SPIDF board as a transmitter for the DVD-1920. It would just be redundant. The reason it makes sense for the Oppo is that it converts the DSD to PCM. The Denon does not.

Cheers!
Russ

My thinking was to use a SPDIF module for PCM and a separate connector for DSD. That was the need for some kind of switch inside the Denon would be avoided. But I would still need a switch in the DAC for this, but only to activate the DSD signal, the PCM would be regular SPDIF. Another way of doing it might be to run both PCM and DSD inside the same cable, say a cat5 network cable. But I would still have to switch it in the DAC. Did you get anywhere on the automatic switching using the SACD LED?

Looking forward to the SDIF3 module

[krgaunt]

Originally posted by wildmonkeysects


Ross, could you elaborate on the reference system(s) that you heard? Amps, speakers, power conditioners, room treatment, the works. We wanna know what toys the boys at ESS get to play with...and to help frame a reference for us to compare our experiences with.

Straight ESS demo board, or something snazzier? Do you know what filter settings, modulator bits settings, etc?

WMS

Sorry to take so long to reply, vacation schedules and it took a little while to get back in touch with Bob at ESS.

The ESS demo room is 8'x12'x24' with 8" thick walls with internal sound dampening. It's HVAC is isolated from the building. A concrete slab physically separates the building slab from the demo room.

Equipment list:
CD/SACD Player: Denon DVD-1940CI (modified with DSD/Serial out jumper cable)
DAC board: ESS 8-channel Sabre Reference board (with metal film caps and Crystek crystal)
DAC: ES9008 Sabre Reference DAC
Op Amps: AD797 (3 per channel)
Receiver: Denon AVR3808CI
Front speakers: B&W 801 Series 2 with stands
Center speaker: B&W HTM1
Rear speakers: B&W 802
Subwoofer: None
Speaker wire: Std Monster cable
AV connectors: Std RCA cables

The demo board was the same one that ESS has made available on their web site. So there was nothing special that they were doing that wasn't disclosed by them. It's also the same board that was used in the comparisons done the an outside company. I was impressed how open and fair they were regarding the comparison testing. They needed a true comparison of the Saber chip for themselves, and they were happy to hand out copies of the test results.

In the list above, you will notice no subwoofer. Didn't need it, the 801's sounded awesome.

The interesting thing about listening to various CDs, not every CD sounded incredible. A lot of the sound depends on the quality of the recording, of course. For example, my standard CD copy of Dark Side of the Moon was lacking in sound quality...but then again it was recorded in '72. But every piece of music we listened to was noticably improved by the Sabre chip. Well recorded pieces had an openness and depth that the sound straight from the Denon (and into the B channel of the amp) didn't have.

RossG

[rossl]

Originally posted by krgaunt

The interesting thing about listening to various CDs, not every CD sounded incredible. A lot of the sound depends on the quality of the recording, of course. For example, my standard CD copy of Dark Side of the Moon was lacking in sound quality...but then again it was recorded in '72. But every piece of music we listened to was noticably improved by the Sabre chip. Well recorded pieces had an openness and depth that the sound straight from the Denon (and into the B channel of the amp) didn't have.

RossG

I will whole-heartedly agree with that statement. New material that has been mastered well and the newer remasters of old tapes can sound fabulous. Older CDs that were not mastered with care... well, I don't listen to them very much any more because the flaws in them are much more apparent.

Have you guys noticed something. I don't know if it's just me, but... when I listen to a good recording on my system with the Sabre8 DAC, then go away to do something, the good recording will stick in my brain and play over and over in my mind. The badly recorded material I just forget about and it doesn't stick in my brain.

Am I going crazy or what? The good recordings just stick in my head because they sound so real.

Ross L.

[woodturner-fran]

OK - more progress!

The buffalo is assembled and everything powered up exactly as expected. +/- 15V for the IVY seems very stable and the 6V/6.5V for the DAC seems very stable too. I've just connected it to my PC (USB to SPDIF converter) but what I'm hearing is heavily distorted with crackles all the way through the music. It also seems to have a hard time locking on to the SPDIF signal. Crackling is worst on bass notes.

I'm off to try it with a non-PC source next although I've never had problems before.

Will report shortly with photos and more details.


Fran

[woodturner-fran]

If I move the SPDIF input to D1 will it still work OK with other sources do you think? And would there be any impact on the sonics ( I think I might have some wima fkp in that range)





Fran

[OzOnE_2k3]

Hi,

@Russ / anyone...

I've just ordered a Sabre ES9008 chip on it's own and will be starting a board design very soon. I'm looking at using it for both stereo and surround material as part of my first amp build...

I just wondered if anyone had given thought as to how to multiplex the DAC outputs so you can combine the eight outputs into two channels for stereo, then back to eight channels for surround playback? This would give the best sound for stereo music while keeping the costs down for multichannel (should hopefully also sound awesome from what I've read on this DAC).

What about an (8:1) x 2 mux IC from Analog? Would this give resonable crosstalk figures and matching?....

http://www.analog.com/en/switchesmul...cts/index.html

I've thought about using relays, but that would require eight DPDT relays (since the outputs are differential) and would be a tad cumbersome - is there a simpler way of doing it (without using manual switches)? Or, you could use a set of relay contacts 'across' each pair of outputs to be combined so they will tie the outputs together when activated?

Do the digital inputs on the Sabre also need to be combined when in stereo (quad-differential) mode?

Thanks,
OzOnE.

[R-K Rønningstad]

What about separate I/V converters for all current outputs, and then do the summing to stereo with summing amplifiers after the I/V stage? In other words, you do not sum the currents at the DAC outputs, but rather after separate I/V stages. Correctly configured, one can then have both stereo and surround from the same chip, just a matter of switching the digital inputs between 2 channel and surround.

Rolv-Karsten

[OzOnE_2k3]

Hi,

Aaah, I see. So I could just use buffers after the outputs which would permanently give a combined output (alongside the separate outputs), then just switch to that for stereo?

But, how much would that degrade the output compared to joining the DAC outputs directly (from the point of view of the added SNR that the combined outputs would achieve)?

Would using buffer amps even work properly as far as the DAC is concerened - ie. are there strict phase / delay / freq requirements for combining the DAC outputs to achieve the added SNR?

OzOnE.

P.S. btw, does anyone have a working link to the ES9008 datasheet as I seem to have 'misplaced' the copy I had?

[R-K Rønningstad]

Exactly. That was the idea.
Considering opamp I/V converters I would think it would be the same. Thinking about it, it should be the same if one uses resistive I/V converters as well.
RK