[Folsom]

I thought I read there was a linear technologies opamp in it... Perhaps I was wrong.

Anyways... I did a small experiment on my own... Ground the cases of the capacitors. I just wound wire and connected to where I have everything grounded in my amp. This is probably only important for signal capacitors. However I would especially do it for anything feeding data.

The reason I did it was after trying the grounding the speaker basket I found an improvement. However A-Bing was impossible. The reason became clear it was discharging and not recharging right away. The air, heat, everything is a factor... However I found when playing with the capacitor case and grounding with an analog meter I got minor discharge (so small I was not sure I did see it). I think the skin crawl effect directly has a large effect with the case of the capacitor creating a charge. The reason I speculate this is bad is because it is robbing the current of the subtle information in the capacitor, hence making it less smooth. The subtle information removal becomes pretty pronounced the more and more it is removed, kind of like compression, no attack and decay left.

I am thinking this might help you a lot, like say with not finding OSCON surface mounts. It might also allow us to have success with things like Rubycon's Z stuff that some think is a little to harsh.

[*Scotty*]

DOS, are you talking about grounding the case of a through hole electrolytic capacitor. I am unclear on this point.
Scotty

[randytsuch]

Hi DOS
If you look at the buffalo schematic, there are four ic's on it.
There is no opamp on the dac's output.
The IC's are the DAC, the SPDIF receiver, a PIC that initialized the DAC at power up, and what is either a comparator or opamp (IC3).

I am not sure yet what IC3 is for, but it is not on the output.

For the cap thing in your last post, what caps have you grounded, type, application and what kind of unit? 
More information would be appreciated, because it is the first time I have heard of this "tweak", and it is interesting

Thanks
Randy

[sts9fan]

DOS
Russ is and has been offering some pretty cool kits to the DIY commuity.  To knock them for their cap choice is pretty lame.  When was the last time you designed a DAC using a cutting edge chip?

I mean surface mount caps? Gag.... the only ones I can think of are some FC's maybe FM's, but so few out there. Plus they seem compromised, I bet they build a charge quicker in the case and cause the sound to be harsh. That is what I would guess, because I think they sound harsh.

[Folsom]

I am doing my tweak on BlackGate N type 100uf.

I guess in all situations you should check pin to can to make sure they are isolated as it is not always the case. Peter Daniels mentioned sometimes cans have higher voltage on them, but I am not sure why unless they are unisolated. If they are isolated and running high voltage on them you would need a better connection. I guess this is a case by case basis. I however think when possible for signal capacitors this could be a very nice thing to do. It really smoothed out my music, added more imaging in particular with things like high frequencies (the shorter ones that otherwise are more affected first, short lower power frequencies would probably be most subject to cap can draw).

Another fellow mentioned "However there is some leakage from the -ve terminal to the can that may raise the can voltage towards the -ve potential."

The next question was anti-corrosion connection. However if the voltage on the can is very minimal I doubt this is a big concern. If it is higher and you are going to use whatever, a pipe clamp or something, it might be a problem. (not that I know grounding high voltage cans would be a good idea.

I do think Twisted Pear is cool, but again at the same time the level of care that is expressed by some DIY creators, that play with stuff until it sounds good, and confirm it with other trained ears, is a whole new level. Designs are good but the listening experience can vary. Specs on paper do not always equal pleasant to the ear. The only things that make me question how good some things actually would sound is the taint of sonic signiture from sometimes too cheap of components. I have made kits from different places, and sometimes they have a real cheap kit but through in some Nichicon Muse capacitors or something just to make the output better etc.

[Folsom]

I guess someone on my particular amp found -35v on the can of the capacitor. However I have to wonder what the amperage is, .001 micoamps or? Again I guess it requires testing.

One thing for sure though is that there is no need for it to be on the can. Even more sure is there is no need for it to draw electrons (information) from the inside of the capcaitor...

[multibit16]

The Buffalo's op-amp is used as a buffer for the 3.3v supplying the Sabres VREF left and right pin.
Its important the voltage here is the cleanest possible

[randytsuch]

My buffalo is in the mail, got notice today  .
I think I was pretty early in the line, for this batch of buffao's, and they said they would start shipping this batch this week.

I was going to mate it with an SB2, but I ended up buying a Duet last Monday, during the ebay/live "sale", so I decided to build a Duet/Buffalo box.

The Duet puts out normal I2S, from what I read, so I will probably put them right next to each other, and run the Buf off if I2S.

Randy

[TomS]

My buffalo is in the mail, got notice today  .
I think I was pretty early in the line, for this batch of buffao's, and they said they would start shipping this batch this week.

I was going to mate it with an SB2, but I ended up buying a Duet last Monday, during the ebay/live "sale", so I decided to build a Duet/Buffalo box.

The Duet puts out normal I2S, from what I read, so I will probably put them right next to each other, and run the Buf off if I2S.

Randy

Wasn't aware of that for the Duet receiver, so no reclocker needed there to run straight in?  Cool!

[BillB]

Would a tube I/V be heracy for a DAC like this?

-OR-

Better yet, does anyone know how an Aikido would handle current output? (probably not well)

[Folsom]

Would a tube I/V be heracy for a DAC like this?

-OR-

Better yet, does anyone know how an Aikido would handle current output? (probably not well)

No but class A tubing would be what I think would be best due to the nature of the DAC and the kind of resolution it should be capable of... screw slurring.

I actually think tube might good to counter the sterile sound that you may encounter with such high resolution plus make the power issues more acute with their presence. (Doing the mods talked about by the link I have in this by some guy on the DIY audio forum with R core transformers and a few other things would probably make this world class high end with a couple of other implementations, capacitor banks, Vishay S102's, Teflon caps if need be, regulated and CMC'ed power after R core and before, etc...  However no matter how much of that stuff you do to make the dynamic range, resolution, imaging, etc, magnificant, you still may not get the same feeling from listening to it unless you do something almost silly like throw in some Riken resistors, or a tube stage, maybe Mundorf Silver/oil caps etc, cheaper stuff that can make things sound fun. 

How does it sound Randy?

[lord dubious]

My buffalo is in the mail, got notice today  .

I know you probably only just got the kit but it would be great if you kept us updated.  I struggle with the hundred page threads at diyaudio.
Cheers

[mgalusha]

Mine is in the mail as well, this should prove an interesting project.

[multibit16]

Buffalo sounds very good as standard but feed it some  supplies using Paul Hynes regulation and it sounds excellent

[randytsuch]

I will post when I get a chance to put it together.

I am busy with Christmas stuff right now, and we are going on a short road trip right before Christmas, so it will be a  little while before I have anything to report.

Randy

[BillB]

Mine came yesterday...it is in the closet to be delivered by Santa.

Not sure why the bastard couldn't build it out first before gifting it. 

[poseidonsvoice]

Buffalo sounds very good as standard but feed it some  supplies using Paul Hynes regulation and it sounds excellent

I agree. I was thinking of the Buffalo but using only Paul Hynes shunt regulators for the power supplies, that's a lot of shunt regulators and the costs add up, especially if you are going to use the IVY output stage as well...

Anand.

[multibit16]

Buffalo sounds very good as standard but feed it some  supplies using Paul Hynes regulation and it sounds excellent

I agree. I was thinking of the Buffalo but using only Paul Hynes shunt regulators for the power supplies, that's a lot of shunt regulators and the costs add up, especially if you are going to use the IVY output stage as well...

Anand.

Yes, I agree these cost more than standard off the shelf regs, but for the increase in performance they have make them worth it, I've tried lots of regs including PFM Flea, ALW super regs, Teddy regs etc and  Pauls are by far the best IMHO.

Using Z1A-15, Z1N-15  shunts for the IVY and Z1A-3v3 shunt for the main 3.3v on the Sabre brings a big improvement, the other regs for the 1v2 and separate VREF left and right increase performance further, I wanted to get as much as I could out of this dac.

The cost for a commercial dac to offer this sound would cost a hell of a lot

[HT cOz]

So how did this come out for the people who were building it?

[S Clark]

Well, like the man said, how did they turn out?

Scott