FX Feedback loop

[DanZParticipant]

Hello,
Yesterday I had a very sad experience on stage with the QUPAC.
It was not very clear what every fader is doing when selecting the left FX tab , and navigating through the auxes
I unfortunately moved a fader and BOOOOOOOOOOOOOOOOOOOOOMAAAAAAAAAAAAAAAAAAAHHHHCHHHRR
a fx feedback loop that almost killed speakers and ears of people. I was so chocked that I did not know what to do to stop this.
Fortunately someone unplugged the general power chord after 15 seconds….
it is so dangerous… why not preventing this by a software update, with this fader being disable or colored on the iPad app?
The return fader that sends to the same FX…

By the way, can someone explains me what are the 4 ret / 4 send faders in this FX tab , that can be changed for every aux and LR ?

[GigaParticipant]

Yeah, that’s a bitch….. Luckily that happened to me when I was testing out things at home.

What you did was feeding the output of the fx-unit back into that same fx-unit -> BOOOOOOOOOOOOOOOOOOOOOMAAAAAAAAAAAAAAAAAAAHHHHCHHHRR

The left set of faders (returns) are to be assigned to (usually) FOH only.

But I agree, a better safetynet would be to omit the assign-buttons “to itself” alltogether.

Giga

[[XAP]BobParticipant]

Pah – safety nets are for wimps 😉

There are so many different ways to trip yourself up with routing loops though…

The FX1 return doesn’t necessarily get information from the FX1 mix bus – so there isn’t an ‘easy’ check to put in here.

[MarkPAmanParticipant]

With delay effects you may actually want a loop, much easier to control on a fader than in the edit screen. The default has it turned off & down anyway. As you’ve got to turn it on AND up before you get a loop, I’d say it was pretty safe already…..

[Dick ReesParticipant]

Dan…

The cardinal rule in such situations is to undo the last action. There is no reason why the feedback should have lasted more than a fraction of a second, much less 15 seconds or so. You’ll learn sooner or later.

This does not really belong outside of general discussion. To place it as a request for a feature is frankly ludicrous…almost needless to say. We all know that attempts to “idiot-proof” a system simply breeds a more virulent strain of idiots.

[Anonymous]

I’m pretty much a strain of a virulent strain of idiots.
The forums are quite all over the place however that sometimes works out beneficial to opening the eyes to other prospective users.
Remembering we have gone through a really massive change from analog to digital.

So in this situation an UNDO would be really handy to newbies.
If a feed back scenario occurred like this a quick button push would be so handy! On QU series maybe?

But then as George says “Know what you’re doing”
So that brings to the mind, know exactly what you are turning off and on.
I guess study the manual before going live.

[GigaParticipant]

The pitfall in this particular situation is that sometimes it can rear it’s head long after turning up that return fader. Depending on other settings it can take a while before the total system hits the levels where it starts going south.
Which in return builds a case for “prepare and try before you go live” I guess…..

Giga

[robbocurryParticipant]

Getting very fimiliar with your mute buttons on the iPad and qu-pac will make life a lot easier.
After decades using analog mixers, I found myself looking everywhere for a big shiny tangible fader rather than to the iPad or soft keys when the unexpected happened.😳
Panic can take over.
Only practice/time/training with new equipment will give you a chance of stopping small problems becoming big ones. 😀

[MarkPAmanParticipant]

In “festival” type situations, when unexpected things may happen, I will usually have all of my outputs on one DCA fader. Normally this just sits at 0dB, but it’s there to turn things down a tad (or a lot) quickly if/when something goes wrong. Stop the horrible noise first, then you have time to work out what caused it.

Running Qu-Control on my phone means that I’ve got access to the DCA in my hand (or at least, in my pocket) wherever I am, even if somebody else is running the desk. I duplicate that DCA in the same position on every Qu-Control page, so I can always find it fast.

Most of the time it doesn’t get used, but it’s nice to know it’s there.

[DanZParticipant]

I also want some reverb on the AUX because of the singer like to have the reverb on the monitors too

Also, I like to send the delay into the reverb to get a more natural delay

I am not that idiot and have some experience in digital and analog mixers, but I must say, I still don’t understand 100% of this FX send / return screen

And while moving faders I ve got the feedback loop, and my first instinctive reaction was to move away and turn myself to save my ears

Unfortunately the iPad then said DISCONNECTED probably because the distance (not so far) ;….

So even muting the LR did not react

I don’t think it is hard to add in the QU app or the firmware :

Just disable a FX SEND FADER that return to ITSELF

[FabParticipant]

I think you should first understand the logic of your qu desk..
these things (fx loop etc..)happen on all mixers

[DanZParticipant]

Yes for sure.
In my Yamaha analog mixer, there is no AUX SEND knob on the reverb return track (send to the reverb unit)

Why adding a knob that will for sure create a feedback loop?

[Dick ReesParticipant]

Dan…

Please do not be offended, but the reality is that you simply need more experience and preparation. You cannot blame the hammer when you hit your thumb.

[[XAP]BobParticipant]

Just disable a FX SEND FADER that return to ITSELF

That’s not a simple ask.

I suppose the desk could disable the Mix2 send from the FX4 return if that happened to be the configured input – but what if there are analogue loops in play as well?

The cardinal rule is to “know thy routing” and – if you want a safety net. Put it in wherever you can.
If you start the day be un-assigning all inputs from all mixes and just add in what you want then you’ll never accidentally hit a digital loop – because the default state is ‘no signal’ unless you have asked for it…

[DanZParticipant]

I am not offended. I don’t blame anyone. Just give an idea to disable the MIX2 send from the FX2 return track, if they are linked together internally.

We don’t have to blame the car when someone is driving into the wall. But we are happy to buy a car with the seat belts included

No need of disabling a send, but detecting when you move a fader. just before the fader changes the value of the fx send, it does a simple test. Are we inside a fx return track? if yes. another test. what input is feeding this fx ? if answer is mix2 , Are we actually raising this input ? => Cancel this move

For sure I will try to understand the fx send / return tracks in the FX tab for each aux.
This is the only part of the QUPAD that I still don’t understand 100%, and was fatal

For sure. I am now traumatized and will never move those fader again during a show :p

Dan

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