The value of the cap will depend on several parameters, here's a calculator;
Coupling Capacitor Calculator by V-Cap
Ray
, got my replies re-reading the topic with calm. 
The BOM is correct and works for me, but it's up to you and you don't have to stick to it...
Ray
I've assembled the board and it works I think. Just the mute doesn't seem to mute properly under certain conditions. I have to do more testing on that.
Just to check, if the format is not DSD, do you get distorted sound on one channel? I get distorted sound like some fuzzy sounding version of the music on the left side. No sound on right side. When DSD is playing, it's fine on both channels.
Just to check, if the format is not DSD, do you get distorted sound on one channel? I get distorted sound like some fuzzy sounding version of the music on the left side. No sound on right side. When DSD is playing, it's fine on both channels.
Good stuff.
The mute will not eliminate all the pops, particularly on 'Stop' and you'll need to tune the delay period with the trimmer pot to minimise pops on 'Start' - the pot changes the delay period. I suspect the pops experienced will vary depending on which USB board you use.
It is a DSD-only project so you will not get listenable results with other formats. I just get noise if I mistakenly play non-DSD media but have never listened to it to see which channel etc.
Ray
The mute will not eliminate all the pops, particularly on 'Stop' and you'll need to tune the delay period with the trimmer pot to minimise pops on 'Start' - the pot changes the delay period. I suspect the pops experienced will vary depending on which USB board you use.
It is a DSD-only project so you will not get listenable results with other formats. I just get noise if I mistakenly play non-DSD media but have never listened to it to see which channel etc.
Ray
Isn't this a mistake? Thought you have to set EVERYTHING to DSD output
and not Dsd Over Pcm, or am I wrong?
Sorry, I wasn't specific enough. I'm using DoP rather than native DSD.
I don't really get the pot tuning yet. I tried turning it clockwise and counter clockwise and the delay changes but not ideal yet. I guess I'll experiment with it a bit more.
Thanks Ray for making the boards! It's sounding very nice.
I don't really get the pot tuning yet. I tried turning it clockwise and counter clockwise and the delay changes but not ideal yet. I guess I'll experiment with it a bit more.
Thanks Ray for making the boards! It's sounding very nice.
Another suggestion I have is for the connection from relay to the audio output. Instead of having wires connecting them, why not have them as traces?
Relay Pin 2 & 9 route to JLSound Pin 11 (Analogue Ground)
Relay Pin 3 & 8 route to L and R Output Pads (Output terminals)
Relay Pin 4 & 7 route to the LPF output (ie connection between Rf and Cf)
I'm not sure if that was considered but it'll be less messy to do muting on the PCB. Also, this would be for SE. For FF board, you'll have to figure out what is the ground reference for the differential output.
I'm not sure if the 555 timer is required if using logical AND of Pins 7 and 8. I could try to capture the logic states to see.
Relay Pin 2 & 9 route to JLSound Pin 11 (Analogue Ground)
Relay Pin 3 & 8 route to L and R Output Pads (Output terminals)
Relay Pin 4 & 7 route to the LPF output (ie connection between Rf and Cf)
I'm not sure if that was considered but it'll be less messy to do muting on the PCB. Also, this would be for SE. For FF board, you'll have to figure out what is the ground reference for the differential output.
I'm not sure if the 555 timer is required if using logical AND of Pins 7 and 8. I could try to capture the logic states to see.
Waiting to arrive the FlipFlop boards I was looking for unbalancer circuits & remembered that I own an old Legato 1.0.3 so why not use only the unbalancer circuit? Also remember to extract the four jumpers J1, J2, J3 & J4 to only power the unbalancer section.
Attachments
Ah, I see.
DoP works fine with the no-dac approach as it gets unpacked and it is DSD that is output on the header pins. DoP is just a means of sending DSD data over an Ethernet connection by packing it into PCM packets. However, I understand DoP is limited to DSD128 rate. My own experience with DoP via the JLSounds board is that if you send it DSD256 it will work but only with one channel outputting music (the other channel was quiet as I recall). At DSD128 I couldn't hear any difference between DoP and native DSD, the reason I now use exclusively native DSD is to be able to use DSD256, which moves the potential noise issue further from the audio band.
Ray
Possibly, but isn't is easier to just only send DSD (or DoP) data in the first place?