High frequency noise with PELUSO 2247LE

[astral_car]

Hi everybody,

I am stuck with a problem with my peluso 2247LE.
I get an annoying high frequency noise out of it. It comes and goes and makes
the mic unusable. Here's a clip showing the problem:

******//dl.dropbox.com/u/1716999/pelu...noise-test.mp3

The peluso is the only mic showing the issue, no problem with dynamics
or with an AT4050 that I have.

Let me say that I sent the mic back for repair, waited three months, just to get the mic back with the same problem it had before leaving my little studio (part of the pain is documented in this thread: ******//www.gearslutz.com/board/moan-...rs-beware.html ).

Does anybody experience the same problem? Do you have any suggestion?

Thanks in advance for any help,
Andrea

[noiseflaw]

Originally Posted by astral_car

Hi everybody,

I am stuck with a problem with my peluso 2247LE.
I get an annoying high frequency noise out of it. It comes and goes and makes
the mic unusable. Here's a clip showing the problem:

******//dl.dropbox.com/u/1716999/pelu...noise-test.mp3

The peluso is the only mic showing the issue, no problem with dynamics
or with an AT4050 that I have.

Let me say that I sent the mic back for repair, waited three months, just to get the mic back with the same problem it had before leaving my little studio (part of the pain is documented in this thread: ******//www.gearslutz.com/board/moan-...rs-beware.html ).

Does anybody experience the same problem? Do you have any suggestion?

Thanks in advance for any help,
Andrea

Excuse me but is this a joke?...

Forgive me if it isn't - but it just sounds like you whistled into the mic, high frequency whisltling?...

[astral_car]

Originally Posted by noiseflaw

Excuse me but is this a joke?...

Forgive me if it isn't - but it just sounds like you whistled into the mic, high frequency whisltling?...

, no it's not a joke. and yes it's true that I whistle in the end,
just after I hear the noise it's actually there and stops. If you listen
to the mp3 with headphones you will also hear the noise *before* the
whistle.

Thanks,
A.

[Batchainpuller78]

Oh yeah I hear it, It actually pitches down to silence before the whistle. it's good to hear without headphones as well.
Weird, sure that's only with the Peluso???

[astral_car]

Originally Posted by Batchainpuller78

Oh yeah I hear it, It actually pitches down to silence before the whistle. it's good to hear without headphones as well.
Weird, sure that's only with the Peluso???

only with the peluso. and with any pre I have (stt1, bae 1073, orpheus pres)

I actually kept the peluso on for 24 hours, and yesterday did some recording and didn't notice any noise... really strange.

[Batchainpuller78]

hmm, yeah can't explain it, can't help, just can say I hear it too, well it disappears in this sample as well so it's intermittent.
and the frequency change is also very weird it goes piiiiiiiiiioeeeeew after you say hi-is.
Get some mic guys in this thread and Peluso as well

[Batchainpuller78]

and? did you get rid of the noise?

[LeeYoo]

Hi astral car,
Had a listen to your mp3 clip. Ran it through a spectrum ananalyser. Don't know what to think of it. The first part with your voice contains a low level, narrow 8000herz tone and a broader 15.5khz spectrum. These spikes are usually found in cheaper A/D converters. These digital tones shift with the chosen sample rate. The second part contains only the broad 15.5khz noise. Not sure what to think of the whistle. If this is not a joke, I would first eliminate any external source, like the sound is not coming from anything in the room, or maybe a transmitter like a cell phone. If the noise is made by the microphone itself, I would suspect the valve or the parts directly around it, as this is the only ACTIVE element. Other parts like leads, plugs, caps, resistors etc. cannot MAKE any sound, especially not a constant spike like this. Unless there are also active parts in the supply. Maybe moisture is a factor as you said that after a long time of running, you did not hear it anymore. Maybe other channels in your A/D are doing it. Keep an open mind till you narrow down the source. Try recording on a DAW with a TFT analyser window running. You can then see in real time where the problem in the spectrum is, and maybe gently tap the microphome or the supply, or wrigle the plugs etc.

[astral_car]

Originally Posted by Batchainpuller78

and? did you get rid of the noise?

I noticed that If I warm up the mic for a long time (more than 1 hour)
it is less likely to happen. That partially solved my issue.

[astral_car]

Originally Posted by LeeYoo

Hi astral car,
Had a listen to your mp3 clip. Ran it through a spectrum ananalyser. Don't know what to think of it. The first part with your voice contains a low level, narrow 8000herz tone and a broader 15.5khz spectrum. These spikes are usually found in cheaper A/D converters. These digital tones shift with the chosen sample rate. The second part contains only the broad 15.5khz noise.

Thanks !

I have a Prism Orpheus as converter, and it doesn't show any noise
on any other microphones.

And regarding the whistle in the end, it is actually me softly whistling
but *after* the other noise has gone, and it was a instinctive
reaction after perceiving that the noise was there.
I have other clips of me playing guitar where the noise actually
comes up (where I don't whistle, btw )

As I wrote I found out that the noise is less likely to show up is the mic
is warmed up for a long time.

Thanks for your suggestions!

Cheers,
A

[Matti]

No harm done if you opened the mic and cleaned the tube pins

Matti

[noiseflaw]

Originally Posted by astral_car

, no it's not a joke. and yes it's true that I whistle in the end,
just after I hear the noise it's actually there and stops. If you listen
to the mp3 with headphones you will also hear the noise *before* the
whistle.

Thanks,
A.

Apologies,

I gave it another listen - with headphones on. Yeah I hear a high pitched noise @ about 8247khz - is that it?...

Reminds me of the noise my old 828 MKII made when it had a momentary freak, before I solved it with a factory reset.

[rbreen]

Have you used it in a couple different studios besides your own? If you take it elsewhere and the problem disappears, the problem is most likely not the microphone at all, but something in the studio itself.

[davey boy]

When I got my 2247le I had a noise as well. I called Peluso and they said they knew about it and the fix was to use a ground lift. In America it's a little 2 pronged AC adapter that the AC cord plugs into prior to the wall. Not sure if Europe has such things. They cost about $1 here. Any, that fixed it and I've had the mic for a few years now with no issues.

[tampa]

Excuse me for asking, but might this be a tube problem?

[astral_car]

Originally Posted by tampa

Excuse me for asking, but might this be a tube problem?

The tube has been replaced afaiu when the mic was sent back to the US for repair

[astral_car]

Originally Posted by davey boy

When I got my 2247le I had a noise as well. I called Peluso and they said they knew about it and the fix was to use a ground lift. In America it's a little 2 pronged AC adapter that the AC cord plugs into prior to the wall. Not sure if Europe has such things. They cost about $1 here. Any, that fixed it and I've had the mic for a few years now with no issues.

Actually the peluso is connected to a furman power conditioner (P 1400 AR E) that should shield for ground issues.

[astral_car]

hi,

******//dl.dropbox.com/u/1716999/pelu...elusoNoise.aif

this new audio clip compares the noise floor of an audio technica 4050 with the one of the peluso 2247LE. Same pre, same gain. The first seconds of the clip is the audio technica, the last the peluso.

Note that this just the sound of my room, so to hear the "shape" of the noise you should wear some headphones and turn up the volume a bit.

My question is: is it normal that the peluso is much noisier than the Audio Technica?

The preamp is a BAE 1073, 55 db of gain.

Thanks for any feedback,
A.

[astral_car]

well, yesterday I opened up the mic power supply and regrounded the power plug, i.e. I soldered a wire from the ground tip to the metal chassis of the power supply. Before there was no wire, just some soldering iron on the ground tip.

It now seems that the noise has disappeared, and the mic is usable again!! thumbsup


A.