my double PCM1794DAC projet

[skygtr]

system diagram

 

[skygtr]

PCB

 

[skygtr]

the test

mute off noise

ch1(up) test BW 0--20MHZ
ch2(down) test BW 0-95KHZ

 

[skygtr]

UV meter

full=100uv BW 0--95khz

 

[skygtr]

-90db 1khz sine

ch1(up) BW 0--20mhz
ch2(down) BW 0--95khz

 

[skygtr]

-80db

 

[skygtr]

-70db

 

[skygtr]

-60db

 

[bou]

Do you have the schematic of your DAC??

 

[galouche]

I'm building a 2xpcm1794 dac too (perhaps 4 x pcm1794) but directly with the I2S output of my CDPRO2. I like your design and the color of your pcb 🙂 It seems you've done it in single face the front face is for the separate grounds ? Are you coupling the grounds and how ( capacitors, ... )?

what about your I/V opamp choice ? I have 6 opa827 and I'd like to test them in my DAC ...

 

[s_volkovoy]

Two channels of PCM1794 works as differential DACs? if so, how do you generating digits for it, inverting?

 

[shyliang]

skygtr:
I'm trying to build my DAC with DIR9001+PCM1798,
but I found that DIR9001 had no data output on Dout
when used the 24.576MHZ XTI. I want to know how
did you make it work at this point.Thanks.

 

[huyanlou]

good!😉

 

[skygtr]

I used the Samplitude software to generate the test signal and burned on to a CD.
the CD track:

1) mute
2) -90db 1Khz Sine
3) -80db 1Khz Sine
4) -70db 1Khz Sine
5) -60db 1khz sine
6) -50db 1khz sine
7) -40db 1khz sine
8) -30db 1khz sine
9) -20db 1khz sine
10) -10db 1khz sine
11) 0db 1khz sine
12) CH L 100Hz sine
13) CH LR 100Hz sine
14) CH R 100Hz sine
15) CH L 1KHz sine
16) CH LR 1KHz sine
17) CH R 1KHz sine
18) CH L 10KHz sine
19) CH LR 10KHz sine
20) CH R 10KHz sine
21) CH L 20KHz sine
22) CH R 20KHz sine
23) CH LCR sine
24) -6db 100Hz Square
25) -6db 1kHz Square
26) -6db 10kHz Square
27) cannon 18

my double pcm1792DAC I/V use opa604.
schemaic post to later.

 

[shyliang]

THANKS.
Hope to see your SCH.

 

[spencer]

Interesting project!

What is the function of EPM 7032?

How does it sound compare to other DAC like PCM63?

What regulators are you using on the left side?

 

[skygtr]

part1 sch

 

[skygtr]

part2

 

[skygtr]

part3

 

[galouche]

Hi skygtr,

Thanks for the schematic.

Do you have the resistors and condensator values for the I/V and the differential amp ? I'm simulating my circuit and I'm interested to compare 🙂 You put condensators between th in + and the in - of the diff amp ? I've seen them in some datasheets. Could you explain ?

Thanks in advance 😉