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Adagietto 22nd August 2020 12:50 AM

Urgent problem with AEA TRP + uln-8
 
1 Attachment(s)
Hi everybody,

I just got an AEA TRP to use with my 2 Coles 4038 and my Metric Halo uln-8.
I made a first test. The sound is beautiful but I get a strong and weird noise that make the takes completely unusable.
I recorded the noise in Pro Tools and put it in attachment here.

Anyone would have an idea about how to solve this?
I have a recording session in a few hours and it is really stressful.

Many thanks,

Jean-Philippe

Mr P 22nd August 2020 01:18 AM

JP,

You will need to systematically go through your setup to determine where the noise is getting into the system.

Is the noise there if you use different (hopefully known good) mic cables into the TRP? if yes then:

Is the noise there if you use different mics into the TRP? If yes then:

Is the noise there if you use different cables between TRP and ULN8? If yes then:

Is the noise there if you connect mics directly to ULN8? If yes then:

Is the noise there with nothing connected to the ULN8?

Answering these questions will get you along the way to identifying the source of your problem.

Regards,

P

David Spearritt 22nd August 2020 04:32 AM

Sounds like it might be mic pre noise. Can you compare AEA with ULN8 pres with Phantom off of course?

brhoward 22nd August 2020 05:21 AM

Sounds a bit like a cell phone, or RF device, too close to an unbalanced connection or near the ribbon mic.

David Spearritt 22nd August 2020 07:23 AM

Quote:

Originally Posted by brhoward (Post 14928124)
Sounds a bit like a cell phone, or RF device, too close to an unbalanced connection or near the ribbon mic.

Yes, it does sound a bit like that.

Adagietto 22nd August 2020 09:04 AM

Thank you.
I forgot to mention that the two Coles are mounted in Blumlein on the dedicated bar.
Strangely, the noise is a bit less powerful when I inverse the polarity of one single channel on the TRP.