• MFS90
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Topic: Strange recording glitches Fireface 800

Hi.
Recently i notice a strange audio glitches printed to my audio.

https://i.ibb.co/6vpWpGz/1.jpg
https://i.ibb.co/xjb4SZn/2.jpg

Reaper 7 (same with older versions) 64 FP double precision mixing engine
192 kHz 2048 samples latency in RME driver

https://i.ibb.co/dgBVRZR/image.png
https://i.ibb.co/60BFDgV/image.png

NO plugins at all in the session, i'v print my analog console mixbus to ADC.

That spots of the waveforms, that i mark on screenshots, sounds like crackles.

I'v start to get them when i change my analog gain stage and start to print very dense mixes to ADC.
-7.0 LUFS-I is the case (We don't discuss here why and for what. Please.)

I'm not sure, but if i print a little bit lower gain output of my mixing console mixbus to FF800,
seems to this problem not appear in my audio.
I don't understand why.

For example - i drive same hard my previous audio worse audio interfaces (Presonus Firepod 10) and have zero problems like i describe.

Now i test lower gain level and report here.
I want to double check.

Please, help me figure it out!

2 Reply by MC

  • MC
  • MC
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  • From: Germany/Thailand
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Re: Strange recording glitches Fireface 800

Check the inputs with a simple sine wave, up to 0 dBFS. That makes it easier to see if input level influences the effect.

Was the power supply of this unit ever renewed?

Regards
Matthias Carstens
RME

MC's Website

  • MFS90
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Re: Strange recording glitches Fireface 800

Hi. Thanks for reply.
I will try sine wave but i will be changed by console circuit (it colors a lot).
I don't know about PS i'm second owner and can't find out this now.

I heard yesterday strange noises in headphones, like crackle static.
This happened yesterday for the first time and was unpredictable. I turned off the device and turned it back on after a while and the problem disappeared.

I also tried yesterday to make the print one decibel quieter and the audio turned out normal, without the above problem.

I don't understand what is causing these problems. Could electrolytic capacitors lose their capacitive rating?

  • waedi
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  • From: Swiss Zürich
  • Registered: 2020-12-08
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Re: Strange recording glitches Fireface 800

Yes the capacitors can lose over time their power but then the unit will no longer work.
This looks more like a damaged converter or simply a dying power supply.
Time for sending in to service.

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue
  • MFS90
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Re: Strange recording glitches Fireface 800

Strange. I don't have any loose electrolytic caps in any audio interfaces (Presonus, Motu) that same age as FF800.
I doubt that RME use worse caps then thees vendors.

Impossible to ship. Please don't ask why.

What should i check in the PS?
I have a little electronics fixing background.
Changing non SMD caps, diodes etc i can do by my own.

Plus, i have a thought: maybe it's not inputs. Maybe it's high gain outputs?
When i turn down my DAW tracks that i send to DAC outs of FF800 -->Console-->Back to FF800 ADC
problem goes away.

6 Reply by MFS90 (edited by MFS90 2023-10-20 16:13:22)

  • MFS90
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Re: Strange recording glitches Fireface 800

MC wrote:

Check the inputs with a simple sine wave, up to 0 dBFS. That makes it easier to see if input level influences the effect.

Was the power supply of this unit ever renewed?

I try sine wave. Dumb loud. -1.4 LUFS-I

https://i.ibb.co/vc2Zktf/image.png

Record those sine like a 30 minutes take.
Only bugg i have that always on start of recording something goes wrong.
You can see this on screenshot.

https://i.ibb.co/G5N2zv6/image.png
https://i.ibb.co/tBTnqgh/image.png

7 Reply by MC

  • MC
  • MC
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Re: Strange recording glitches Fireface 800

I asked for dBFS. What you mention is useless in determining real input and output levels. That sine wave is not loud but already heavily clipped, equalling higher than 0 dBFS input level.

Regards
Matthias Carstens
RME

MC's Website

  • MFS90
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Re: Strange recording glitches Fireface 800

Sorry for misleading.
I run signal generator and push tone to 0 dB full scale to outputs.
https://i.ibb.co/cT7xF39/image.png

Clipping is from my analog console path.
We don't speak about clipping here. Only odd sudden glitches that i show in my first post.

9 Reply by S-E Hansson (edited by S-E Hansson 2023-10-22 07:33:34)

  • From: Gothenburg, Sweden
  • Registered: 2007-05-01
  • Posts: 441

Re: Strange recording glitches Fireface 800

Hi!

As Matthias Carstens ask above...

"Was the power supply of this unit ever renewed?"

I did that repair a long time ago for my FF 800 (from 2004)
and have been working fine since so try that repair of the Power Supply

even try and check with earth grounding e.t.c

regards S-EH

  • MFS90
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Re: Strange recording glitches Fireface 800

I doubt this is something with PS.