1 (edited by hunsitho 2024-02-05 08:39:53)

Topic: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

Dear forum members,

A first post after 15 years as a RME user - a rather good sign. :-)

I realized that when I have my device (guitar, synth, whatever) connected to the front Input 1 of my FF800, and I change the settings in the panel from "Front" to "Front+Rear", I loose a lot of db (from 17 dB to 30 dB, in my particular test case).

Having the same device connected to the rear, and changing the setting from "Rear" to "Front+Rear", the volume stays constant.

Also when trying the same on Input 7 or 8 (device connected to the front, changing setting from "Front" to "Front+Rear"), the volume stays constant.


Does Input 1 have a different behaviour to the others, or does my unit have an issue?
(as I never realized this before, I expect the latter...)

Could somebody with an FF800 do me a favour and check this for me, please?

Thanks a lot in advance!
Thomas

Music lover with lots of gear, little talent, but loads of enthusiasm!

2

Re: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

From the manual:

Instrument Options
Limiter activates a soft-limiter with a threshold of –10 dBFS. Note: The Limiter can only be switched off with input selection Front.

Does that explain it?

Regards
Matthias Carstens
RME

Re: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

Thanks for your quick reply, Matthias!
Unfortunately not.
I forgot to mention that all optional checkboxes (Drive, Speaker Emulation, Limiter) are OFF.

(I should also mention that I started looking into this as I suddenly got digital noise and hiss on channel 1, and I am pretty sure it wasn‘t there before. Thus there is a fair chance there is some kind of damage to the 13 yo device. It might just be a ground loop, obviously, but that would not explain the loss in dB.)

Music lover with lots of gear, little talent, but loads of enthusiasm!

4

Re: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

Might be. Typical failure is the input OP amp of channel 1. That can be easily fixed by any competent technician, replacing that part.

Regards
Matthias Carstens
RME

Re: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

Ok! Vielen Dank, Matthias.

I might bring it to the „audio ag“ professionals for a check.
Living in Munich, Haimhausen ist just around the corner…

Thanks again for your quick help!
Thomas

Music lover with lots of gear, little talent, but loads of enthusiasm!

6 (edited by hunsitho 2024-02-05 08:38:02)

Re: [Solved] FF800 level decreasing switching to "Front & Rear" on Input 1

Hallo Matthias and everybody,

the story continued:

I realised the following day that I find the same digital hiss also on my SPL Channel 1 Instrument input, even after disconnecting it from everything but power.

Further investigation showed that the hiss came from the devolo Powerline adapter that was plugged into the socket next to my music rack power supply.
The devolo being equipped with an internal filter, connecting the rack through the devolo's built-in socket solved that issue completely, both on the Channel 1 as on the Fireface.

With that knowledge, I looked into the level topic again, and I think that you were actually right, Matthias, and I misinterpreted the line from the manual.
"The 10 dB limiter can only be switched OFF with input selection Front."
Which - how I get it now - means, that it is ON when "Rear" or "Front+Rear" are selected.
Thus you get the same volume if you use the Front Input WITH the Limiter, or "Rear" & "Front+Rear" without.

So: no need to repair, as nothing is broken, and Matthias @MC gave me the right hint (I should have taken) in his first reply! :-)

Thanks again and regards,
Thomas

Music lover with lots of gear, little talent, but loads of enthusiasm!