TOPIC:

Hi guys,

Something really strange happened on my system, and I'd like to get your view for an explanation (fortunately it's solved now).
It's driven by a cascade of SHDs, 1 studio as master > 1 regular shd per side (pre Flex time).

Yesterday while I was swapping a bunch of amps to test them, a very strange effect appeared.
I can only describe it as an echo with very short cuts like digital clipping (reminded me of 56k modem).
But it was very faint in the background, had hard time to convince myself it was not normal.
It was easier to spot with dialogs, on the left side only. Not really disturbing with music, except the fatigue appearing quickly.

You bet I first thought it was the amps, so checked them all again in different setups.
Then maybe it was an artefact of my new tuning for the amps, new crossover with maybe something going on the phase etc, so I redid it multiple times...was going crazy.
After a last tune that objectively could not sound bad I decided to also check the full range sweeps through the master, just to make sure the signal was the exact same than per each slave (I never had any issue there before).

Right side was ok, left one not! It could not be a coincidence, I was already thinking the worst.
I started by swapping sides / restoring all devices / checking all cables > nothing changed.
Then for the sake of it I finally replaced the AES interconnect... and yes that was it, back to normal!
I'm relieved, funny the effect it could have, and it was much more dramatic than just the FR variation displayed here, the signal itself was disturbed, but strangely not on the highs.
Attached: the artefact in blue/green, with new cables in blue/red with master/slave offset

So can a digital cable go bad just like that? I swear it was tight fit, I checked multiple times.
If not the cable then the shd, my 4 years old one has already lost its spdif-in, it just doesn't work, maybe something is going on inside on the AES too.