Squealing/feedback problem..

rednebb

rednebb

Inspired
I have used my AX8 several times for solo gigs where I've connected it directly to various house PA systems and haven't had any problems with feedback or anything, but today I used it with my Matrix Q12A at a band rehearsal for the first time, and it squealed/fed back like crazy on drive/high gain settings (and I'm talking classic rock type drive/high gain, nothing extreme at all..) I had to turn the volume down so I almost couldn't hear myself and/or I had to move far away from the Matrix. I was playing at normal rock band rehearsal volume, not extremely loud, and I haven't had feedback problems at this volume earlier with other gear (including my old Axe-Fx) What can be the reason for this, and how can it be fixed..?
 
was your q12a closer to your guitar than with the other setups? facing your guitar pickups directly?

gain is gain and feedback is feedback. it's a physics issue usually.
 
Chris@AxeFxTutorials said:
was your q12a closer to your guitar than with the other setups? facing your guitar pickups directly?

gain is gain and feedback is feedback. it's a physics issue usually.
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No, the Q12A was placed behind me on an upward angle maybe 6 feet away, like I normally would place a regular combo amp, and I haven't had feedback problems before at same volumes and with same type of drive/high gain sounds, neither with regular combos nor the Axe-Fx. And I wouldn't actually call it a normal feedback either; the moment I turned up the volume on one of the drive/high gain patches, there was an instant high pitch squeal..
 
I've occasionally, well, rarely, had incidence of squeals with an up angled monitor. Seemed to just be one particular venue. Lots of diamond plate panels on the ceiling around the stage... aCk!
 
This is known as "tweeter squeal" and occurs because the electromagnetic field from the speaker's tweeter couples into the pickups. As you noted the solution is to turn down or move away from the speaker. Lowering the gain will also help.
 
FractalAudio said:
This is known as "tweeter squeal" and occurs because the electromagnetic field from the speaker's tweeter couples into the pickups. As you noted the solution is to turn down or move away from the speaker. Lowering the gain will also help.
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Ok, but the Q12A contains a coaxial speaker with no tweeter, AFAIK..? Plus I can't recall having this problem earlier with the Axe-Fx/Q12A setup.
 
rednebb said:
Ok, but the Q12A contains a coaxial speaker with no tweeter, AFAIK..? Plus I can't recall having this problem earlier with the Axe-Fx/Q12A setup.
Click to expand...
on coaxial speakers the tweeter ( high frequency driver ) in located in the center of the 12" speakers, a coaxial speakers is the same as a traditional box but with the highs in the center.
 
I had some chance to do some experimenting on my own today, in the same room I rehearsed with the band yesterday, and found that the placement/angling of the Q12A could affect the squealing/feedback a little. And to my surprise, placing the Q12A right behind me (normal amp placeent) seemed to be the worst spot.. I also noticed that when I just turned up the volume without touching the guitar strings, everything was fine, but just touching one string (especially the G string) resulted in an instant hight pitch squeal.. So it seems to me, this isn't like normal feedback at all.. Furthermore, I tried to plug the AX8 into a Roland Cube that incidentally was in the room (set to ultra clean..), with the same results, so the Q12A is not the problem. And about the guitars I were using; yes, they were both strats with single-coils, and I know they can be prone to feedback of course, but these are trusted guitars that I've used on several loud gigs with other combo amps and also the Axe-Fx before, without any similar problems. For the record, I also plugged the guitars straight into the mentioned Cube with high gain setting and approx. the same volume, and I had no squealing/feedback there. So it seems the problem must come from the AX8 in some way..
 
Some things to keep in mind, some parameters that cause an higher risk to get squealing:
When you can't hear enough details with a real amp you turn it louder until you can hear them. With a modeler you might get tempted to add highs or presence when tweaking at lower volumes. Such sounds don't work right in the rehearse when you play loud.
When you tweak sounds at lower volume you also might turn the gain knob too high compared to what you would set it to when you play loud. That's because when you play loud, the cabs or monitors feed a bit back to the strings and gets them to resonate which adds sustain and makes playing easier. Retweak gain in the rehrarse, there you get away with less gain and a sound that cuts better.
Even that I know about these problems I run into that trap from time to time, it just doesn't feel wrong when you tweak something at lower volumes.
 
Hm, ok, but is it normal that just touching the string lightly will cause an instant squeal..? Like I said, I've had both the Ultra and the II earlier, and I can't recall having this problem with those.. And also, I want to point out that I'm talking about relatively low gain drive sounds here; "classic rock " tones, no hi-gain metal at all, so if even as low gain as this causes squealing/feedback problems, I wonder how all the metal guitarists can cope with this..?
 
Gday Rednebb,
Is it possible you have a gate setup so that touching the g string, opens the gate and starts the feedback?

Thanks
Pauly
 
rednebb said:
Hm, ok, but is it normal that just touching the string lightly will cause an instant squeal..? Like I said, I've had both the Ultra and the II earlier, and I can't recall having this problem with those.. And also, I want to point out that I'm talking about relatively low gain drive sounds here; "classic rock " tones, no hi-gain metal at all, so if even as low gain as this causes squealing/feedback problems, I wonder how all the metal guitarists can cope with this..?
Click to expand...

It shouldn't happen at lower gain unless the highs are boosted a lot.

Just one string starts it? Sometimes the part of the strings behind the nut/ at the tuners starts squealing. Damp the string there one by one to try to avoid it or pick the strings there to force the squealing and listen if it's the right sound...you hear when you hit the right string.
 
The older Atomic tube models with a woofer and a tweeter/horn used to be BAD about that type of squeal. I still have one and
it would squeal when I turned a certain direction, but not the other way. Didn't matter if I had the strings muted or not. That was
a pain in the arse to say the least. Good luck with it!
 
666was999 said:
It shouldn't happen at lower gain unless the highs are boosted a lot.

Just one string starts it? Sometimes the part of the strings behind the nut/ at the tuners starts squealing. Damp the string there one by one to try to avoid it or pick the strings there to force the squealing and listen if it's the right sound...you hear when you hit the right string.
Click to expand...

Any string can start it, but at least on one of my strats the G string is the dominant one.. But as I said, this guitar doesn't cause squealing/feedback with a normal combo set to high (or even higher..) gain at the same (or even louder..) volume in the same room, so again, the problem is apparently not the guitar(s)..
 
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