M7CL Word Clock Error

All week long the sound crew guys in the church-house have been troubleshooting an issue with our Yamaha M7CL-48 digital mixing board.

I’ve only got rudimentary skills for working the board, but has a super-neat digital touch-sensitive display, lots of sliders, more that a few knobs and lots and lots of blinky-lights.

Yamaha also offers a M7CL StageMix app for iOS that lets me adjust the computer sound output from my iPad without having to get up and walk over to the board itself. Handy the few times I have to perform double/triple duty running the projectionist PC, the video camera mixing board, and the sound board all at once.

Anyway, the mixing board was displaying a banner error message at the bottom of the digital display along the lines of there being a “word clock error”.  The different sound board operators fiddled with it off-and-on during the week but weren’t able to clear the message. It didn’t seem to stop the board from otherwise working normally but was a nuisance when it rhythmically popped up.

So last night they were talking about it again and I just did a quick visual inspection “chasing the wires” and the various components.

I quickly noticed that our media input deck (CD track player unit, dual cassette deck player, and PreSonus Light Pipe unit) was powered off. Hmmm.  I flicked the main rack on-switch and everything sprung to life.

And the error went away.

Turns out the digital sound mixing board was connected into the PreSonus FireStudio 32x32 ADAT Lightpipe unit so we can output into a different PC (oft forgotten) to do 32-track audio recordings directly to the PC for super-important audio captures. It eats up a LOT of HDD space with the files but is really cool if you want to do some serious audio-editing. Of course it is almost always forgotten as a capture source so recordings on it are few-and-far between.

I digress.

The board has been set up in such as way as it looks for the Lightpipe unit for the word-clock signal. No Lightpipe then you get the word clock error on  the mixing board display.

Case solved and black electrical tape has now been placed over the rack master power button to prevent accidental power shutdowns.

Cheers,

--Claus V.