Buffalo DAC (ESS Sabre 9008)

[Russ White]

Originally posted by Vadim
I am looking to get the Buffalo-IVY-Dual-power-supply kit, when it becomes available, and use with my DCX2496. I have a question regarding the implementation of the IVY circuit.

Looking at the schematics of IVY board
http://www.twistedpearaudio.com/imag..._schematic.pdf

I noticed that the Low-Pass filter is a 1st order and has a cut-off frequency of 202 kHz. I also looked at White paper published by ESS Technology
http://www.esstech.com/techsupp/Appl...PCB_Layout.pdf

and there the filter is a passive 2nd order network implemented around the AD797 with a cut-off frequency of about 100 kHz.

The ESS White Paper does not seem to mention the oversampling rate of the Sabre DAC, so it is hard to comment on the appropriate anti-aliasing filter order or its cut-off frequency.

Still, why not use a lower cut-off, - perhaps in the 50-60 kHz range, because the 20kHz pass-band will not be effected by any more then a tiny fraction of a dB in this case anyway while getting a benefit of better noise suppression? Comments?

Vadim

Hello,

That's an older version of the schematic. I have redesigned the circuit slight for a lower Fc. (<100khz).

I found it is actually necessary to filter beyond what I had been at first.

We will update the Schematic soon and publish a manual for the different possible configurations. The IVY is used for more than just the Buffalo, so it hard to capture all possible configuration directly on the schematic.

Cheers!
Russ

[matjans]

another one

[nicoch58]

Spaghetti ? Good spaghetti!!

[avr300]

Originally posted by matjans
Hey guys,

just to let you know I just built my Buffalo after the normal startup-problems: soldering station was missing/lost (i recently moved to a new house), out of solder (on sundays), no room to work, you know how it goes .

Current state: spaghetti! I plan to put it in a nice case sometime, but i'm really waiting (lurking in the dark) for the uber controller.

Soundwise: *very* good. Wide, stable, accurate soundstage. Quite neutral, i think. Lots of detail, especially in the lower (bass) regions.
I'm using it with a sonos as source (the only thing I had with volume-controlled spdif output, for lack of balanced diff. preamp) and a pair of UcD400's as amp.

Looking good. And just to make sure, it the Buffalo, an IVY and a couple of PSU's, right ?

[matjans]

Originally posted by avr300


Looking good. And just to make sure, it the Buffalo, an IVY and a couple of PSU's, right ?

yep, buffalo, ivy, dual supplies as in the kit, with the update pack russ sent (*great* service btw!).

[Russ White]

Originally posted by matjans


yep, buffalo, ivy, dual supplies as in the kit, with the update pack russ sent (*great* service btw!).

Hi matjans.


Just have to say it's Brian who deserves most of the credit there.

Hope you enjoy it!

Cheers!
Russ

[ataylor]

Hi Russ,

Forgive me if this has already been covered -- it's a very long thread...

On the Twisted Pear site the Buffalo DAC appears to be "out of stock" but recent posts seem to indicate that it's available. If it is available, I would like to order one.

Thanks!

-Alex

[Russ White]

Hi Alex,

Brian is out on vacation for a bit. We have boards and parts when he gets back he will be putting together some more modules. For now they are out of stock. We will post news when their availability is eminent.

Cheers!
Russ

[ataylor]

Hi Russ,

Sounds like Brian deserves a vacation. I'll keep checking back often...

Alex

[eclectic2k]

Russ & Brian,

hope you both get a nice vacation sometime :-)
you're a great asset to the community. I just got my OTTO boards a few days ago, now I just need to assemble it and set it up as my new home theater bypass switch ;-)

back to the buffalo:
Will the buffalo be offered as a *full* kit? I'm running low on hobby funds so I'd rather go cheap on this. If so, I'll keep an eye out for pricing & availability once Brian gets some time...

Note: I'm more than familiar with SMT assembly, and my soldering skills are quite decent. (I also have professional help available locally as a plan B) So I'm more than willing to trade more work for cheaper cost.

Thanks!
-Chris