Mr White's "Opus", designing a simple balanced DAC

[Russ White]

Originally posted by DarrenWadsworth
I have one spdif reciever, 2 dac boards and one LCPS. Eventually I want to add a USB reciever board.

1st. Can I use the LCPS for the first 3 things? If so, is there a wiring diagram that can show me what goes where. I have this, but it is only for single DAC:

Will I need to change any of that if I get the USB module?

Thank you

Darren

You just need the one PS nothing more.

Just run a second set of wires to your second DAC, just like the diagram you posted is fine.

You won't need to change anything power supply wise for the USB module.

Cheers!
Russ

[ichiban]

I have the SPDIF Rcvr>Met>Opus set up into an LM4562 preamp.

It had been playing superbly, then when turned on one day the
system was giving out a low EEEEEE sound? Swapped equipment,
still there. The noise plays thru regardless of which input I have
selected?

I disconnected power to the whole Opus board setup
and the noise is gone.

Any ideas.

[Russ White]

Originally posted by ichiban
a low EEEEEE sound? Any ideas.

That sounds sorta like oscillation/ motorboating...

I would need to know more about how you have it setup.

[ichiban]

Originally posted by Russ White


That sounds sorta like oscillation/ motorboating...

I would need to know more about how you have it setup.

So, I connected the Opus outputs directly to the output rcas
and ran that into the My-Ref. Same thing, EEEEEEEE. Note, when
going thru the Selector>VolCtl>PreampSection it made no difference
whether the dac was selected? and the EEEE amplitude did not
vary with vol setting?

I'm going to change the setup to RCVR>OPUS leaving out the MET
and see/hear what happens.

The power supplies for the preamp and digital boards are separate
and grounds connect at the volctl ground.

This is very odd, as I've said it was playing fine the night before
then no changes between!?

WM8804 RCVR
AIFCONF1 - HI
All Others - LO

OPUS DAC
I2S - HI
DM1 - LO
DM0 - LO
MUTEB HI
MODE LO
IWO - HI
All Others - Not Jumpered

MET ASRC
AUTOMUTE Jumpered
RDY Not Jumped
OWL1&2 LO
OFMT1 LO
OFMT0 HI
MODE0&1 HI
MODE2 LO

IFMT1&2 HI
IFMT0 LO
BYPASS HI
All Others Not Jumped

[OneyedK]

Originally posted by ichiban

MET ASRC

IFMT1&2 HI
IFMT0 LO
BYPASS HI

IFMT2 : LO
IFMT1 : LO
IFMT0 : HI
Bypass : LO

Is the way to go...
--> you selected 20-bit right justified and then put the asrc in bypass mode...

[ichiban]

Originally posted by OneyedK


IFMT2 : LO
IFMT1 : LO
IFMT0 : HI
Bypass : LO

Is the way to go...
--> you selected 20-bit right justified and then put the asrc in bypass mode...

Ooops! I posted those just the opposite of what they are.
I did a quick look to post them and thought those jumpers
(+)(-) were the same as the row on the left side. Now I
see the (+) pins are all toward the center of the board.
Anyway thanks for the response.

[DarrenWadsworth]

Originally posted by DarrenWadsworth
I have one spdif reciever, 2 dac boards and one LCPS. Eventually I want to add a USB reciever board.

1st. Can I use the LCPS for the first 3 things? If so, is there a wiring diagram that can show me what goes where. I have this, but it is only for single DAC:



If not, what will I need to get?

Will I need to change any of that if I get the USB module?

Thank you

Darren

I forgot to ask how the spdif board connects to the 2 dacs in dual configuration.

And how eventually the USB module and spdif module can be connected to a switch.

Please help with this. I am finally going to build this thing the weekend of the 22nd

Thank you

Darren

[Russ White]

Daren, just connect two sets of wires from the "DOUT" terminal block. One set going to each DAC.

[DarrenWadsworth]

Originally posted by Russ White
Daren, just connect two sets of wires from the "DOUT" terminal block. One set going to each DAC.

I feel like such an idiot (ignorant). It seems that no one else is asking these rudimentary questions.

I guess if there were complete instructions for connecting in dual diff mode, I would be ok. I am currently compiling pictures, diagrams and instructions from all of the thread responses. All of your help has been greatly appreciated.

Except that after looking at my "notes" and a pic of a setup from this forum, I see also that the output to the XLR sockets is not what I expected. As all of the terminals are used for each channel. With some of the wires joined. Could you please tell me the proper way to connect the DAC to the channels for dual differencial mode?

Thank you for your help. Hopefully when all is said and done, I might be able to help others on this thread.

Darren

[Russ White]

No worries Darren,

The opus manual covers some of the differential(mono) issues.

The output terminals are switched a bit when you run that mode, so you have to check the polarity from the data sheet which is also in the manual.

I will admit the manual is sparse. I will do what I can to help.

This is a pretty advanced project,with a lot of elements still very much up to the builder.

Cheers!
Russ