Soekris Dam Dac

[nige2000]

Problem solved.
The culprit was one of the rails of the regulator. I didn't notice it upfront because there was a battery pack float charging.

I could find only one diode bridge (D2). Where's the other?

By the way, Audio-GD DA-M1 released with 10% discount.

Regards.

Adolfo

there is only one bridge coz you only need one in this case it outputs pos and neg power gnd is the mid point

[nige2000]

Glad you sorted it!
Thanks for the head-up on the Audio-GD DA-M1 - I note the name is a nod to Soekris product names :)
Have you ordered one of these yet, Nige?
I'm interested but again on this board there's a Xilinx CPLD through which the signals are routed

Not enough info on their site.
Looks like it handles a 24bit signal - two lines of 0.1% resistors in parallel to give 0.05% accuracy but don't know the quality of these Rs
€14 less without the resistors
Looks like it's using LVC574a which looks to be a parallel input rather than serial input of the LVC595 shift reg
This parallel input is one of the functions the Xilix CPLD provides

LVC595 has double the output current (+/-50mA) of the LVC574 (+/-24mA)
Both have the same output skew time of 1.5nS - is it too small to worry about?

had assumed you knew about the audio-gd r2r i ordered a few last night
not sure if its a toy or not but its got plenty of options to play with

i assume the guy is getting it difficult to get 1704's for his dacs and this is the back up plan but the 1704 were sign magnitude aswell

the potato 74 374 chip would be a good canditate for flip flop

if you were buying z-foils would cost up on 200€ per channel

i dont think what ever soekris uses is that expensive by some of his comments less than 30 bucks or so
maybe there not as expensive as we think

[jkeny]

had assumed you knew about the audio-gd r2r i ordered a few last night

:) I looked at them a week or so back & these were my thoughts- knew you would probably order some :)

not sure if its a toy or not but its got plenty of options to play with

i assume the guy is getting it difficult to get 1704's for his dacs and this is the back up plan but the 1704 were sign magnitude aswell

the potato 74 374 chip would be a good canditate for flip flop

if you were buying z-foils would cost up on 200€ per channel

i dont think what ever soekris uses is that expensive by some of his comments less than 30 bucks or so
maybe there not as expensive as we think

I would consider using HF melf resistors - don't know if they come in 0.1%?

[nige2000]

had assumed you knew about the audio-gd r2r i ordered a few last night

:) I looked at them a week or so back & these were my thoughts- knew you would probably order some :)

not sure if its a toy or not but its got plenty of options to play with

i assume the guy is getting it difficult to get 1704's for his dacs and this is the back up plan but the 1704 were sign magnitude aswell

the potato 74 374 chip would be a good canditate for flip flop

if you were buying z-foils would cost up on 200€ per channel

i dont think what ever soekris uses is that expensive by some of his comments less than 30 bucks or so
maybe there not as expensive as we think

I would consider using HF melf resistors - don't know if they come in 0.1%?

yea think they do, whats the value?

[jkeny]

yea think they do, whats the value?

Do you mean resistor "value" or benefit?

[nige2000]

value

3k?
Susumu 0.1 % are less than 10c each could be something like that their using

[Val33]

i am just returning to my shelved 1121 project. I put it on hold early last year in the hope that Nigel was going to attack his and give us mere mortals a guide on what to do but alas this has not happened.

Has anyone modified one yet, on the lines of the mods made to the 1021? I'm comfortable with the simple suff, removing the output caps and mute relays. Supplying the shift registers with 3.3v from lifepo4's looks to be simple enough too. Not sure weather to remove, change or leave the banks of capacitors?

The digital end of the board looks a little more complicated, I am pretty sure that U46 is the only 3.3v regulator there, so I think I can remove that and inject 3.3v Lifepo4 there and directly to the clock. I can't work out U47 and U41 but I think they are the 1.2v. I should probably leave them alone for now!

Anybody any thoughts? Anyone tried anything with this board yet?

TIA

Val

[nige2000]

http://chihhanlin.weebly.com/soekris-oe ... 26512.html

only thing i seen

[randytsuch]

So after a LONG hiatus from audio, I'm reviving my system.
Booted my audio pc last night, worked fine once I put RAM in it lol.
Should have music playing in a couple of days, have to remember what I was doing before I stopped. Ohh, and I blew up my sd trans, one of the main reasons I took a break.

Wondering if anybody doing anything new with their DACs?

Randy

[rickmcinnis]

Sorry to hear about the sdtrans.

How bad is it? Just not working or a charred mess?

Glad to see you back.