Guitars phasing out? WTF???

[Fredrik-Ablaze]

So ive tracked guitars with the following mic setup:
SM57 off axis, Sennheiser E609 where dustcap meets cone and a ribbon mic on another speaker.

I've also reamped a DI through the same cab, using the 57 and here's the weird bit:

When playing back the 609 and the 57 everything sounds okey but when adding either the reamp or the ribbon microphone to the mix every now and then the whole mix freaks out and all preassure is lost, leaving only fizziness...

I dont quite know what to make of this? When soloed every channel by itself sounds fine, but summed together they freak out...

Of course I've checked phase on all channels and they align well, even when the sound gets fizzy...

What the hell could be causing this?

Crap speaker on the ribbon mic? There's no audible difference on the track though.

Crap amp?

It doesent happen to L and R simultaneusly, it more alternates from side to side intermettent...

How do get this sorted out??? I had to return the reamp box so reamping the DI's again isnt really possible...

 

[Jordon]

The tracks might look in phase, but aren't. Try nudging the re-amped and ribbon mic tracks around sample by sample.

 

[Fredrik-Ablaze]

But they sound in phase for like 30 seconds and then WHAM, the sound goes weak.

 

[dani]

i'm gonna guess and say your mic stands weren't solidly set.. if one of them is drifting down, even slowly, it's gonna have hugely weird effects on phase. the wave lenths of the freq's involved are small, so even a slight drop is gonna sound odd.

my advice would be to pick a single mic, eq to taste, and just go with that? perhaps blend in an 8505 with impulses?

thanks,

 

[John_C]

+1 for dodgy mic stands.

keep at it though, don't take the easy way out

 

[Fredrik-Ablaze]

I've spent a couple of hours troubleshooting it and I've isolated the problem.
It's either one of my speakers going south, my ribbon mic giving up or the rental preamp we've used for tracking that has a bad solderjoint somewhere.

I'm gonna reamp just the ribbontrack again this weekend, I'm just glad I dont have to replay the whole shit once again.