Hi TP crew,

I have built a BIII board with Placid HD v2 regulators and a Legato I/V stage, with an S/PDIF-4 board, Sidecar and a toslink board, and although it all looks good with what I have measured (i.e. DC voltages look great) I cannot get the LOCK LED to light on the BIII board, the MUTE LED stays on and of course I get no output.

I am including a few pics. Well, I'll try, if it only accepts one attachment I'll add additional posts below.

A few things I have tried:
The output from the toslink board is 2.3v peak to peak.

I made the S/PDIF-4 board with resistors for the following inputs: 1=AES/EBU, 2=TTL, 3=consumer, 4=consumer.
I have tried the toslink board into each of the inputs without any luck. In desperation I have also tried with and without the ground wire connected from the Toslink board, and with and without the Sidecar - no difference in any configuration.

How do I go about debugging this?

Thanks,
Paul

Edited by user Sunday, June 29, 2014 6:30:28 AM(UTC)  | Reason: Not specified

I have tested it with an S/PDIF feed from a CD player. I verified that the S/PDIF feed was ok by connecting it to my current DAC and listening to it - it sounded as expected.

Connecting the S/PDIF feed to the S/PDIF-4 board (attached to the Sidecar and then the BIII) had the effect of making the mute LED turn off, but I have no lock LED (it was still dark) and no output.

How do I determine what board has the error and what it might be?

Many thanks Leon. Yes, I tried the Toslink board directly to the BIII board - no lock or sound.

However, I don't hear the relays switching when I operate the switch so I'll check this, the environment may be too noisy to hear them.

Yes, I have set the DIP switches on the BIII, but now this brings me to a question. I have the latest firmware (had to swap it) and p24 of the integration guide mentions that the switches should all be swapped Off for On etc, but I am not sure I have read this correctly. With the latest firmware should the default position for SW1, 1 & 2, be ON (as indicated on p25), or OFF because they should be swapped? I may well have this wrong.

Thanks,
Paul

Ok, some success!

maybe one of the switches to control the input switching was not correct, but I went back through all of the switches and turned 1&2 of SW2 on and off again, and I have S/PDIF input working - sounds pretty damn good.

I did move the S/PDIF input to the other consumer level input I have configured on the S/PDIF-4 board and can confirm that the input switching works as expected.

I still do not have the Toslink input working... When the Toslink board is connected to the TTL level input I have configured on the S/PDIF-4 board, the lock led flashes and I have small snippets of audio coming out of the DAC.

So I wired the Toslink board to the other (now first) consumer input and it works fine. Sounds bloody excellent! However I would like to know if I have messed up something so that it does not work into the TTL level input as it should. Any ideas?

Cheers and thanks,
Paul

Thanks Brian,

I tried that tonight - no change, well, the lock light did not even flicker... So I'm still a bit confused that the Toslink board will not work into a TTL level input. It works fine into a consumer level input though, so I have music.

If there is any way to debug this I would like to know.

Thanks,
Paul