The ADA8000 problem has been solved! Josh came round and took a look at the studio (and also, I might add, gave me an excellent idiot’s guide to tuning drums). We pondered the reasons that the ADA8000 was chucking out digital crackles and pops on input channels 9-16, and narrowed it down to three possible causes.
- Faulty ADA8000
- Dodgy optical cable
- Something we haven’t thought of yet
The ADA8000 was acting as a digital slave to the Digi002 using the ADAT protocol for digital sync, so the Digi002 was to provide audio input channels 1-8 and the ADA8000 channels 9-16, giving me the option of 16 simultaneous inputs (albeit with only 12 of them through the M1F, it being a 12-channel analogue desk).
After various attempts to fix the clicks & pops problem, including rebooting everything with the ADA8000 acting as master, we decided, as a last resort, to try swapping the optical cables. The Digi002 was firing the sync information down its Optical Out, and the ADA8000 was firing audio signals back into the 002’s Optical In. And swapping the cables over completely cured the problem. It turns out that the clicks and pops were not syncing errors – they were corruptions in the audio data coming back into the 002. So it was option 2 all along. Soon I’ll get another (high-spec) optical cable, because although the master>slave info is being carried accurately by the weaker cable, it’s not desirable to have it in there permanently. This is not an uncommon problem, according to Josh – optical cables are not as reliable as some people assume they are, even though they carry digital information.
So even if you’re not a studio geek (I was actually quite excited writing the two techy paragraphs above), the result of Josh’s intervention is simple – I can now have 16 live mics in the studio during a take instead of 8. To test the studio I’ve tentatively agreed to record one of my grads’ bands in September. They get a free demo, and I get to try out all the inputs properly before I need to use them on a time-sensitive project.