1 Topic by michael_pujol (edited by michael_pujol 2023-07-25 05:17:29)

  • Registered: 2022-04-16
  • Posts: 2

Topic: Brand-New Preamps Generate Popping Noises

Hello, fellow RME-People!

I just bought the Babyface Pro FS after having the Babyface Pro for 7 years. Loved the BFP, until I thought it died. Sold it for cheap, as a "dying interface", and upgraded to its newer version. Now I realize it probably wasn't dying at all... sad

The preamps were generating randomly popping noises (≈1/25 minutes, on random preamps), and I troubleshooted it like crazy. One of my tests was my usual setup, but with a cheap (new) Behringer interface. And the popping noise was gone. With an old MOTU interface, the same noise was still there, but much less loud, and much less frequent. So I figured the BFP was simply dying.

Well my brand new BFP FS generates the same pops. This happens when I engage phantom power, and raise the gain a bit (normal use; 20-45Db for ex.). Same results with, or without anything plugged into the preamps. After troubleshooting so much, I've decided to accept that all preamps will make noise, and I'm just being too picky.

But what about the silent Behringer? (louder noise floor, but no pops) Are these kinds of pops normal? I'm always getting the same noise, or something very similar. It's only audible when you start to hear the noise floor (when I boost the volume significantly). Example:

https://imagizer.imageshack.com/img924/4475/2MIrri.jpg
https://imageshack.com/i/po2MIrrij

Audio Sample:
https://drive.google.com/file/d/1tnJIB- … drive_link

IMO, this is reasonable volume boosting; I don't have a concrete number, in Dbs, but it's what you'd do to a quiet source in some contexts; the pop could be audible to the average listener (it starts to be noticeable from 20Dbs of boost). In the example, I raised the gain, so the noise floor is higher than normal. But should that pop really stick out so much like that?

I also compared to an ancient E-MU 1820M interface, and oh boy, that old thing is WAY more noisy...

So I hope people here say it's normal, and I just never noticed how noisy a noise floor can be. But if it's not normal, I'll list all the tests I did (like a million).

Thanx smile

  • Registered: 2016-06-14
  • Posts: 1,142

Re: Brand-New Preamps Generate Popping Noises

Hi
Some (high quality) preamps generate lots of self noise as long there is nothing connected to them. It’s not the same self noise as with a mic or another resistor connected. So to compare the self noise amount of different preamps, you should connect something, for example a mic with an off switch or a XLR plug with a resistor.
Anyway the pops seem a bit strange to me. Do they appear also with a microphone connected?
The weird thing is, I had some comparable pops but with certain mics. In this cases I always was sure it’s the mic, not the preamp.
As far I can tell (I’m really not an expert), it’s related to the phantom power.
Where do you live? Is it in a humid environment?

UCX - FF 400 - Babyface pro - Digiface USB - ADI-2 (original)
Mac mini M1 - Macbook pro - iPad Air2
  • Registered: 2022-04-16
  • Posts: 2

Re: Brand-New Preamps Generate Popping Noises

oli77sch wrote:

Hi
Some (high quality) preamps generate lots of self noise as long there is nothing connected to them. It’s not the same self noise as with a mic or another resistor connected. So to compare the self noise amount of different preamps, you should connect something, for example a mic with an off switch or a XLR plug with a resistor.
Anyway the pops seem a bit strange to me. Do they appear also with a microphone connected?
The weird thing is, I had some comparable pops but with certain mics. In this cases I always was sure it’s the mic, not the preamp.
As far I can tell (I’m really not an expert), it’s related to the phantom power.
Where do you live? Is it in a humid environment?

Thanks for your feedback! I did try with a microphone; I actually first noticed the noise in a vocal recording session. For sure the microphone's self-noise is louder, so it hides a bit more of the pop, but it's still audible...

Yes, it seems to be related to phantom power indeed.
Not an overly humid environment here.