Topic: Fireface 400 posibly damaged analog outputs

Hello guys.

This week I realized that it's quite probable that 2 outputs of my  young FF400 are damaged. I say young because the unit was bought less than 1 year (2009/02/13!!) ago. It will turn 1 just in a few days.

For two weeks I experienced what I supposed was another channel failure of my old Mackie 8bus on the studio. But on a live concert this weekend I had the oportunity to connect my FF to a good Allen & Heath and the same problems I saw on the Mackie were repeated on the live mixing desk.

So I decided to check the outputs of the FF using my old MFII.

First I checked the inputs / outputs of my MF using loopback. They're not fully crystal clear, as I detected some small variations on the inputs and a relative strong problem on 2nd output. But they're good.

What I did was to connect the 6 rear outputs of the FF400 using balanced cables (new ones) to the inputs of my MF. I set a test tone of 0dBFS using my Ableton Live @ 440 Hz on all the outputs, and my worst fears were confirmed: outputs 2 and 4 of the FF seem to be damaged.

I took a screenshot of the horrible moment:
http://www.solosade.com/obmun/tmp/imgs/ff400_broken-screenshot_mf_input_levels.jpg

I already knew something was wrong, but not that wrong. FF mixer is telling me that a correct 0dbFS level is comming out, so there must be a problem either with the DAC or with the output analog buffer [op-amp, broken condenser...]

The funny thing is that the output attenuation is frequency dependent.
Same test at almost 14 KHz:
http://www.solosade.com/obmun/tmp/imgs/ff400_broken-input_levels_at_14KHz.jpg

And at 51 Hz:
http://www.solosade.com/obmun/tmp/imgs/ff400_broken-input_levels_at_51Hz.jpg

Certainly, quite a difference!

What I would like to ask you is: have you had any similar problems with your Firefaces? Do you find the output of the units sensitive under "hard" work?

I'm asking because I'm surprised. I've been extensively using my MultiFace II, and the unit has withstood all the work without problems. But lately I've been using much more frequently my FF, essentially for on the field recordings [pres come handy] and on my live performances and I'm worried: much of my work depends on the FF!. I wouldn't like to realize this late that I have to be more careful with the new FF400 than with my old MF2!

The unit is obviously under warranty. I will get in contact with my local store and local distributor. But in the meantime, I'm curious... Daniel, Matthias... is this kind of repair handled locally (on your Spanish distributor site) or are the units sent to you in Germany for repair? I'm asking because I'm interested in getting the unit repaired as soon as possible!. This weekend my group Minim is performing on various Portuguese sites and I'm sure I'll be already missing my FF400.

Thank you all for your time in advance and sorry for the big post.

Regards,
    Jacobo

Re: Fireface 400 posibly damaged analog outputs

usually 1khz tone is better to do some test by the way it's a reference measure. Try also -18dbfs that will show you if they are at the same sensibility.

Re: Fireface 400 posibly damaged analog outputs

Hi,

the  unit does seem to be in need of service. Where are you located?


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: Fireface 400 posibly damaged analog outputs

Good afternoon, Daniel

RME Support wrote:

Hi,

the  unit does seem to be in need of service. Where are you located?

Vigo, Spain. So I suppose I should talk to Microfusa ... Could you confirm Daniel? Unit was bought froma local store here. Thanks.

Re: Fireface 400 posibly damaged analog outputs

cigame wrote:

I've had a similar problem with my FF 800. Some of the condensers in the output stages and the power supply had to get changed because of, maybe, too much heat. They had already a bulge on top. Had to send it in. The symptom was the same. Less output level on some outputs.

But you should check your cables by changing left and right.

Thank you Cigame.

That's what I was looking for when I asked in the forum: for the experience of other fellow users. I would expect the FF400 to fail as components wore out with time, but not just after less than 1 year of usage.

A problem related to passive components (specially capacitors) was what I was expecting after seeing the frequency related behaviour. I don't remember having specially overheated the unit... but I cannot tell for sure. And I'm not going to open myself a card under warranty.

On the cables thing, they were new and were previously cross-tested using the other test soundcard (my Multiface 2). So they were almost in perfect condition.

Grag38, thanks for the recommendations. But as I was not specifically doing fine measurements but coarsely verifying that the outputs were just broken, I just chose to get the max output possible level from the FF to stress it as much as possible. Also, I did freq sweeps to check the behavior of the card on the workable frequencies. All showed problems.

Thanks again,
    Jacobo