Experience with this DIY DAC ?

[Bill Fuss]

Well I'm too broke to get any of the pricey transformers, so I'm going Edcor. Three types have been mentioned but no one's really weighed in on which is best (except Bill I think).

PCW 600
XS
XSM

So which one seems best for the DAC?

Hi guys,
I'm still alive, just been working on other stuff lately. I can't comment on the Edcors, are they that inexpensive that they are possibly total crap, don't know. Some have tried them but never reported back so you're pretty much on your own.
Speaking in the minute bit of transformerese that I know, an ideal voltage out DAC trafo would be around 5k imp. so a 10k might actually be a better choice than a 600. BudP has wound some expressly for this but I haven't heard them yet.
They can get terribly expensive and the Law of Diminishing Returns has to kick in somewhere, just don't know when.

Best regards, Bill

 

[McCrackers]

Hey Bill,
Another member(Ciu) has just finished a nice DAC with totally revamped power supply and XSM10K/10Ks and he seems quite impressed(for the price at least) He may want to chime in and elaborate on this. Personally I would definitely give them a try but for now I'm done swapping trafos on the CS4398. Gotta draw the line somewhere.

 

[gabanyayaya]

The output is too low.

Perhaps PCM1794 is the answer like you said....or PCM1798 needs a gain stage like tube....

 

[Netdewt]

Those trafos are ideal for a DAC or preamp, anything over 25va is overkill, but YMMV.
Lots of counterfeit Black Gates on the market now, better off with Panasonics and Oscons.

Best, Bill

Thanks for the heads up. Are there certain caps that should be swapped out or are people doing all of them or...

 

[wushuliu]

Hi guys,
I'm still alive, just been working on other stuff lately. I can't comment on the Edcors, are they that inexpensive that they are possibly total crap, don't know. Some have tried them but never reported back so you're pretty much on your own.
Speaking in the minute bit of transformerese that I know, an ideal voltage out DAC trafo would be around 5k imp. so a 10k might actually be a better choice than a 600. BudP has wound some expressly for this but I haven't heard them yet.
They can get terribly expensive and the Law of Diminishing Returns has to kick in somewhere, just don't know when.

Best regards, Bill

Thanks for the tip Bill. I gotta say though, I just did a little work on the stock board: Took out those first 4 caps after cs4398, replaced the output caps and the 2 2.2ufs before the second opamp with polyprops, and popped in an LM4562 and an OPA2777, and it sounds outstanding. I'm sure the trafos up the game but what I'm hearing sounds so good I'm in no rush to upgrade. Crystal clear and transparent like there's nothing between me and the music. It is miles and miles and miles beyond the stock sound.😀😱

I also swapped out an Alps volume pot in my B1 buffer for one of the cheap ebay smd stepped attenuators, so that may have made a difference, too, but I'm pretty sure it's the dac.

now i'm gonna sit back and

 

[Pano]

The Edcor iron is not bad at all. In fact for the price, it's amazing. I've heard worse for 10x the money.

What a better transformer seems to get you - in subjective terms - is more "life." Better dynamics, better resolution, better soundstage.

But the Edcor are a great place to start. I highly recommend them. If you are happy with the transformer sound, you may wish to upgrade later.

 

[Kooka]

The Edcor iron is not bad at all. In fact for the price, it's amazing. I've heard worse for 10x the money.

But the Edcor are a great place to start. I highly recommend them. If you are happy with the transformer sound, you may wish to upgrade later.

But which model? And, in which configuration (meaning the caps/resistors you used)..?

 

[wushuliu]

But which model? And, in which configuration (meaning the caps/resistors you used)..?

Bill just gave his recommendation for which one in answer to my question up above.

 

[hoverdonkey]

Hey Bill,
Another member(Ciu) has just finished a nice DAC with totally revamped power supply

McCrackers - is Ciu's PS mod posted anywhere? I was thinking of doing something on the PS if it is easy (but like you, am inclined to stopped now!)

 

[gabrielbecheanu]

Hi
It is possible to install in this DAC a new super clock like TentLabs? He will bring any improvements in the sound reproduction. Any one tries a more aggressive tuning? like changing all electrolytic capacitors? or other things?
Thanks

 

[McCrackers]

McCrackers - is Ciu's PS mod posted anywhere? I was thinking of doing something on the PS if it is easy (but like you, am inclined to stopped now!)

Not that I know of. He sent me some pics by email but unfortunately I ran into some computer issues, had to reformat and forgot to backup my emails.
You can try PMing him.

 

[Ryssen]

Those of you that have used Lundahls outputrafos,which model did you use?

 

[Franz Gysi]

Those of you that have used Lundahls outputrafos,which model did you use?

I use LL1690 for the CS4398 DAC.

Great, the absolutely best solution with this DAC imho.

 

[Netdewt]

I use LL1690 for the CS4398 DAC.

Great, the absolutely best solution with this DAC imho.

$125 is a little steep. Any recommendations for something good (maybe not the best) in the Hammond-ish price range?

 

[Netdewt]

Actually I'm probably just confused about the difference between an output transformer and a power transformer?

 

[preiter]

Well I'm too broke to get any of the pricey transformers, so I'm going Edcor. Three types have been mentioned but no one's really weighed in on which is best (except Bill I think).

PCW 600
XS
XSM

So which one seems best for the DAC?

I am using the XSM600 right now. The sound is very nice, but one channel has a hum that I cannot get rid of and I suspect the unshielded transformer is the culprit.

For the price it is definitely worth experimenting with.

 

[tassosk]

Those of you that have used Lundahls outputrafos,which model did you use?

I'm using 1527XL with a TP OPUS (Wolfson 8741) and I'm very pleased with the results.

 

[Ciu]

Hello !

Some mods I've done, with this board, using Edcor XSM 10k/10k

The metalized grey caps are Solid Tantalum glass encapsuled , like Sprague 150D or Kemet (mines are Firca CTS)

On the cs4398 board, 22µf, 16v Vref to Gnd (scratch the black varnish ) pict.#10

replacing black 1000µf, two 140µf // pict #10 on left , mounted on a mini board

Board underside, missing a cap, installed 22µF tantal // adjust voltage resistor

Some white wire, Teflon 0.6mm2

All parts not usefull are discarded, and will be used to build the "filtering" board

About Transfos : Edcor xsm 10k/10k, 12.97$ each !!!
A low pass filter 2 x 270 Ohms // 2nf Silver mica > 150khz

The filtering unit :
9v 10va transfo (not seen)
4 x diodes 11dq10
3 x 3300µF // from board
Transistor Darlington TIP122
1 Pi filter : 1500 Ohms + 1000µF (from board)
2 Pi filter : 300 Ohms + 22µF tantal
Led is optionnal

Just to buy tantal caps, diodes, and TIP122, other parts coming from dismantling board

Filtering Schematic with details to come...

Sorry for by bad English..

Hope this helps ...

Richard

 

[Ciu]

Filtering board schematics added .
You have to control you have ~8-9v at the Tip122 output
TIP120-121-122 are ok, medium power NPN darlington high gain
The filter prevents lm317 to "see" EMI from mains

R.C.

 

[hoverdonkey]

Thank you Ciu (and McCrackers too!).