Topic: Strange beeps on micstasy preamps

Hello,

I have strange problems with micstasy. In certain scenarios, there are strange beeps present on all 8 channels.
There are constant beeps repeating on every second or so.
Here are some observations:
- beeps appear while the microphone with its own power supply is connected to micstasy. Phantom power on micstasy is turned off.
- beeps also appear, while any other condenser mic is connected, but the phantom power is not yet turned on. When I turn the phantom power on,
the beeps go away
- if dynamic microphones are connected, there are no beeps.
- the gain must be set to at least around 40db to hear the beeps.
- If I push the select knob, while the beeps are present, the noise from blinking display appears in signal. It goes away, when display
on channels stops blinking.
- if there is nothing connected to inputs, the beeps are not present.

I have recorded this strange beeps, but I don't have the file on this computer. I can upload it on a server tomorrow.

Micstasy has the latest firmware and is connected via analog outputs. I don't use digital connections.

2

Re: Strange beeps on micstasy preamps

Ground loop or grounding problem. Not only from the inputs, but also from the devices which are connected at the Micstasy's output.

Regards
Matthias Carstens
RME

Re: Strange beeps on micstasy preamps

Wouldn't I hear buzz, hum or noise in micstasy or any other audio equipment in my studio, if there was a grounding problem? Why does this problem dissapear, when I connect dynamic mic?

Today I disconnected all outputs and inputs from micstasy, connected only mic from my control room directly to input, and connected only one output from mistasy directly to my monitor controller (while all other gear was turned off), but the beeps were still present.

I don't have any problems with other gear (including rme octamic II and M32 AD/DA) and I haven't noticed any ground problems.

regards

Re: Strange beeps on micstasy preamps

Could you record them? Does this happen also with no mics connected?

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: Strange beeps on micstasy preamps

I recorded this beeps and I will upload the file on a server, first thing tomorrow.

If nothing is connected to inputs, there are no beeps.
This beeps are only present if condenser mic is connected, while the phantom power is not turned on yet, but the gain is up to 40 or more and also in the case when the mic has it's own power supply and the phantom power on micstasy is turned off. If the phantom is turned on, problem goes away.

regards

Re: Strange beeps on micstasy preamps

Here is the recording of the beeps: Micstasy Beeps
I amplified the level of recording quite a bit. After several seconds, you can also hear the noise, when the select knob is pressed and the display starts to blink.

Regards
Simon

7

Re: Strange beeps on micstasy preamps

There are no beeps in this recording. It's mostly hum from a suspected ground loop, plus a 100 Hz pulse from the display - which should not be there and IMHO is again caused by the ground loop.

Regards
Matthias Carstens
RME

Re: Strange beeps on micstasy preamps

Hi,

I hear beeps, low pulse, static noise and hum here on the mp3 !

regards S-EH

Re: Strange beeps on micstasy preamps

There ARE beeps in the recording. High pitched, present through whole recording.

I also tried disconecting all of the equipment in my studio, pulled power cables out of the sockets, connected only micstasy and monitor controller to the same power socket, but the problem is still there. I am not electrician, but how can this be caused by ground loop? And why does it go away, when I connect dynamic mic?

Regards
Simon

Re: Strange beeps on micstasy preamps

I hear the beeps... What kind of mics are these? And what kind of condensers with their own power supply did you test?

Something may be causing interference inside the mic. Do you have another preamp to test a similar scenario with?


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: Strange beeps on micstasy preamps

I tried all kinds of condensers.... Blueberry, Akg, Earthworks.... The one with it's own power supply was Grove Tubes Gt60.

I tried same scenario with Octamic II, Shadow Hills mono gama preamp, Biz MK preamp and toft preamp. They all work fine and there are no problems.

Regards
Simon

Re: Strange beeps on micstasy preamps

Which display exactly is blinking? Do the blink and beep go together?
Could you test the Micstasy's digital outputs as well?

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: Strange beeps on micstasy preamps

They are all blinking. Blinking noise is not related to beeps, but I just recorded it anyway.
I will test madi outputs and report back.

Re: Strange beeps on micstasy preamps

Simon wrote

And why does it go away, when I connect dynamic mic?

Phantom power broken ?
I mean heard only with condenser microhones engaged !
just trying to help

regards s-EH

Re: Strange beeps on micstasy preamps

S-E Hansson wrote:

Simon wrote

And why does it go away, when I connect dynamic mic?

Phantom power broken ?
regards s-EH

This beeping only occurs with phantom power turned off. If I turn it on, the beeps stop.


Daniel: I tried with madi outputs and the beeps are still present.

Regards
S.

16

Re: Strange beeps on micstasy preamps

Seriously, with that amount of hum I wouldn't care about the much lower leveled 3 kHz sound - but first try to fix the other stuff...then the 'beeps' might be gone too...

Of course you can always send the Micstasy in for a check, but as you noted in a typical test scenario chances are small the error will show up at all at the repair department.

Finally: if the problem goes away with Phantom Power on - then just use it that way...the power supplies in front should be able to handle this.

Regards
Matthias Carstens
RME

Re: Strange beeps on micstasy preamps

MC wrote:

Seriously, with that amount of hum I wouldn't care about the much lower leveled 3 kHz sound - but first try to fix the other stuff...then the 'beeps' might be gone too....

This hum is only present, if the phantom power is switched off, while the condenser mic is connected to input. As soon as I turn the phantom on, the hum and the beeps dissapear. Also, no problems with dynamic microphones. No hum, buzz or anything.

I just wanna make shure, that everything is ok with my micstasy.

MC wrote:

Finally: if the problem goes away with Phantom Power on - then just use it that way...the power supplies in front should be able to handle this.

True.

Regards
Simon

18

Re: Strange beeps on micstasy preamps

Reading all this again I fear you have led me (others too?) on a completely wrong path. In your first post you state:

- beeps appear while the microphone with its own power supply is connected to micstasy. Phantom power on micstasy is turned off.

I assumed that you had turned the external phantom power supply on (but not the one of the Micstasy). But now it seems you did not. In all the problem cases that you describe you connect a dead brick of metal via some cable to the Micstasy input. The effects observed then are fully normal. And with all 'normal' connections the Micstasy works as expected. So there is nothing wrong with your unit at all.

Regards
Matthias Carstens
RME

Re: Strange beeps on micstasy preamps

MC wrote:

Reading all this again I fear you have led me (others too?) on a completely wrong path. In your first post you state:

- beeps appear while the microphone with its own power supply is connected to micstasy. Phantom power on micstasy is turned off.

I assumed that you had turned the external phantom power supply on (but not the one of the Micstasy).

You assumed correctly. That is exactly what I did. I turned external phantom on, and micstasy phantom off.
This is only one observation. All the others that I state are related to normal condenser mics without their own power supply.


MC wrote:

In all the problem cases that you describe you connect a dead brick of metal via some cable to the Micstasy input. The effects observed then are fully normal. And with all 'normal' connections the Micstasy works as expected. So there is nothing wrong with your unit at all.

That is all I needed to know. Thanks.

Regards
Simon

20

Re: Strange beeps on micstasy preamps

So then there is only one problem left - why the external phantom power causes the noise to show up. Now this might still be ground loop related... that one most probably is earthed (and it should be)...maybe you want to try a different brand / ps too...

Regards
Matthias Carstens
RME

Re: Strange beeps on micstasy preamps

It seems that I am not the only one with this strange beeps. I found this topic here on the forum: http://www.rme-audio.de/forum/viewtopic.php?id=6527