Splitter woes

[zigmond99]

I have an issue with a splitter and would be grateful for some advice.

In my band we use a Behringer X18 digital mixer to mix FOH and IEMs. We’ve been using it for ages and it works great – we’ve had no issues.

On Friday we were playing a gig (our first since lockdown) at a larger venue that has its own PA and FOH engineer. I acquired a splitter (Behringer MS8000) so that we could continue to use our mixer to mix our IEMs leaving the house with a separate feed for them to to mix.

I gave FOH the link outputs, utilizing the transformer isolated outputs for us. We sound-checked and all was fine but halfway through our first song the FOH engineer called us to a halt saying that he had no signals from our splitter. We hadn’t noticed as our in-ears were ok.

I spent a few frantic minutes trying to diagnose the fault, for example I swapped the cables from the splitter to the FOH snake but without success. So we had no choice but to ditch our IEMs and play the gig with floor monitors.

The next day, back at home, I pulled the rack apart. I checked every lead and connection and all were fine. I connected a source to each input and then the pairs of outputs to our mixer and saw, as you’d expect, duplicated channels.

I accept that the Behringer splitter is a budget item. It’s susceptible to AC hum and the transformers are a little noisy. But we can live with these limitations. If needs be I’ll replace it with something better. But before I do that could there be something else that caused this problem? With my limited knowledge of such things I can understand how a transformer output might be affected but we were running these to our IEMs and they were fine. From what I understand, the link outs are hard-wired so I’m struggling to see how they could fail. Could there be something else going on , some sort of mis-match?

Thanks

[Hugh Robjohns]

If it was fine in the sound check there's no reason it shouldn't work in the gig. I would suspect finger trouble from the FOH team.

But just to be clear, you connected your mics to the ms8000, and the outputs to your mixer and the FOH snake, yes?

Were you using any phantom-powered mics, and if so, where were they being powered from?

Were any ground lift switches used?

[resistorman]

It’s a passive device with 8 independent channels, there’s no way all of them would just stop working at once. FOH engineer screwed up and won’t admit it.

[zigmond99]

But just to be clear, you connected your mics to the ms8000, and the outputs to your mixer and the FOH snake, yes?

Yes

Were you using any phantom-powered mics, and if so, where were they being powered from?

None of the mics required phantom power (all dynamic) although I guess that doesn't preclude FOH from having switched it on at their end. In the heat of the moment it didn't occur to me to check. There was a DI-box that was being given phantom power from our mixer but that wasn't connected to the splitter, only to our mixer.

Were any ground lift switches used?

No. I tried flicking them to 'lift' but it made no difference.

[Hugh Robjohns]

Hmmm... it's impossible to diagnose after the event, but I can't think of any scenario that would leave the transformer-isolated outputs working normally and not the direct outputs.

My best guess would be a plugging error at the stage box or console, or a configuration problem at the foh console.

Was it a digital foh desk? Plenty of scope to screw up a saved snapshot etc...

[zigmond99]

Thanks for the replies and the confirmation that it's unlikely to be the splitter, more likely some sore of setup/config snafu. We were the support band so after the headliner had completed their leisurely sound-check we were under pressure to get on, get set up, and get on with it. Plenty of scope for a mistake. We must have done ok as the venue have invited us back. Next time I'll go in with a plan.

[shufflebeat]

Something still doesn't seem right. When you ditched the IEMs, did you remove your own mixer completely?

[zigmond99]

When you ditched the IEMs, did you remove your own mixer completely?

I unplugged the mics from our splitter and ran cables direct from the mics to the FOH stage snake. Basically, I put it back the way it was when the headline band had sound checked.