Best way to control feedback in live situations?

RamboMadCow

Inspired
So I'm hoping there are some very knowledgeable people here who can help me figure out the solution to this problem. I've been playing guitar for quite a long time, but I've not been in a live situation until recently.

First the setup: My rack is an ESP LTD Snakebyte (with the hot Hetfieldl EMG pickups), into a Shure wireless transmitter. The receiver is the GLXD4 rack unit. The GLXD then goes into the Axe FX 3. From the Axe, I send output 1 to a Matrix GT1600FX. From there, they're fed into 2 Matrix 212 FR cabinets. I also have output 2 being sent to a splitter, which goes to our mixer board for IEMs and out to FOH PA systems.

In my rehearsal space with my band, we have a concrete floor and I'm within 10 feet of my rack setup. I had some feedback at that time, so I added a gate, and at the default settings all feedback went away. My gain on the GLXD is incredibly low, almost at its lowest.

Over the weekend, my Metallica tribute band (so...very high gain) played our first show at a venue. It didn't matter how far away I tried to walk away from my rack and speakers, there was that terrible feedback squeal. I turned my power amp down to almost completely inaudible (so we lost stage sound sadly) but even at low levels the feedback was present. I did my best to try and control it while we were performing, but the old school Metallica riffs have a lot of "pause for 2 seconds then play", so a lot of times I didn't have time to turn the nob down, and you can definitely hear the feedback. The venue had a carpeted stage as well.

Does anyone have experience with this and have any ideas on what I could do in the future to stop this? It was so puzzling for me because normally concrete floors are a culprit to feedback, and the venue had carpeted ones, and my rehearsal space is concrete with 0 feedback. But we also don't have all the stage monitors that this venue had. My band is looking to slowly increase when and where we play, and I'd love to find a solution to this so that we come across as more professional and a proper Metallica tribute.
 
It can be many factor but most likely two:
- a buildup of frequencies which start the feedback
- too much gain

I'd go for too much gain.

Other things to consider are: damping the pickup mounting springs (I don't think they play a big role with active pickups), working on your muting and working on the placement of your equipment.
I am sure other people will have some more suggestion, but it's very likely too much gain.

When I played in a thrash/death band, we did a lot of festivals and I wanted to be able to have my guitar in front of the speaker with the volume full open without any feedback. As long as I muted the strings.
 
I don't do much high gain, but you say you added a Gate block with default settings. Where in the grid did you add it?

Also, have you tried just adjusting the gate in the Input block?

I think the recommendation I've seen is to place the Gate block after the Amp block.

Try just turning the threshold down.
 
Oh interesting @unix-guy. I added my gate block at the very beginning of my chain after the input. I could move that around and see if that helps.

If possible, I'd like to avoid reducing gain. I actually had to increase gain because there wasn't quite enough grit for old thrash Metallica. If I reduce gain, it might be more viable to just change the amp to an amp that's naturally more gain saturated. I believe the current amp I'm running is the USA Lead.
 
Oh interesting @unix-guy. I added my gate block at the very beginning of my chain after the input. I could move that around and see if that helps.

If possible, I'd like to avoid reducing gain. I actually had to increase gain because there wasn't quite enough grit for old thrash Metallica. If I reduce gain, it might be more viable to just change the amp to an amp that's naturally more gain saturated. I believe the current amp I'm running is the USA Lead.
Yeah, I think that unless you've disabled the gate in the Input block, it doesn't make sense to add another gate right after.

I'm sure the high gain guys will chime in soon ;)

Also, I know a lot of people recommend the Mesa IIc+ for Metallica...
 
I picked the Lead because the IIc+ is already very very scooped. And while I want high gain, I'm going for more of their current touring tone, which is a combination of a Diezel and a Recto, from what I've seen, with quite a lot more mid added in than they used to run back in the 80's and 90's. The lead seemed to be the best amp to get that done, without the ability to run 3 amps. I'm running 2 amps with a multiplexer for instantaneous switching between dirty and clean. If we could simulate 3 amps I'd probably do a combination of the MIIc+ along with something that's a good bit more mid heavy.

It's definitely been a challenge to find the tone that I'm looking for, but also making sure that I fit in the mix along with my lead and bassist so that everyone can be heard, and our tones sound good individually and independently.
 
So I'm hoping there are some very knowledgeable people here who can help me figure out the solution to this problem. I've been playing guitar for quite a long time, but I've not been in a live situation until recently.

First the setup: My rack is an ESP LTD Snakebyte (with the hot Hetfieldl EMG pickups), into a Shure wireless transmitter. The receiver is the GLXD4 rack unit. The GLXD then goes into the Axe FX 3. From the Axe, I send output 1 to a Matrix GT1600FX. From there, they're fed into 2 Matrix 212 FR cabinets. I also have output 2 being sent to a splitter, which goes to our mixer board for IEMs and out to FOH PA systems.

In my rehearsal space with my band, we have a concrete floor and I'm within 10 feet of my rack setup. I had some feedback at that time, so I added a gate, and at the default settings all feedback went away. My gain on the GLXD is incredibly low, almost at its lowest.

Over the weekend, my Metallica tribute band (so...very high gain) played our first show at a venue. It didn't matter how far away I tried to walk away from my rack and speakers, there was that terrible feedback squeal. I turned my power amp down to almost completely inaudible (so we lost stage sound sadly) but even at low levels the feedback was present. I did my best to try and control it while we were performing, but the old school Metallica riffs have a lot of "pause for 2 seconds then play", so a lot of times I didn't have time to turn the nob down, and you can definitely hear the feedback. The venue had a carpeted stage as well.

Does anyone have experience with this and have any ideas on what I could do in the future to stop this? It was so puzzling for me because normally concrete floors are a culprit to feedback, and the venue had carpeted ones, and my rehearsal space is concrete with 0 feedback. But we also don't have all the stage monitors that this venue had. My band is looking to slowly increase when and where we play, and I'd love to find a solution to this so that we come across as more professional and a proper Metallica tribute.
If the monitors were facing your strings this could create feedback as you move closer to them...
 
I had a similar issue which after some investigation on the forum all seemed to be described as tweeter squeal which is an issue restricted to FRFR monitors/speakers. Have a search and you will find quite a bit of info but for me I had to tweak my presets, notch a few frequencies, and watch that I wasn't getting too close to my Q12 when playing at volume.

Whilst as yet the problem hasn't been completely resolved for me, it is at least manageable and I am sure a bit more work would see it fully under control.
 
Just a theory but might be worth trying

Turn your preamp gain down, compensate by turning your master vol in amp block up (just a little bit), then add some dynamic presence.

The idea is dynamic presence is more noticeable with higher master settings. If you turn the master up just past the sweet spot it tends to get mushy but the presence may bring it back. This could help keep the feeling of gain despite lower pre gain.
 
I'll try all of these suggestions as I have a few months until our next gig so there's plenty of time to tweak and get things right.

I'm still very new to all of these fancy things as this is my first Axe unit, but I was curious if it would help to have a parametric eq toward the end of my chain and try surgically removing the offending frequencies that way. Has anyone tried this and had success, or found the opposite perhaps?
 
If you are using fractal to model the real world, a guitar cabinet speaker has frequency limitations, so a lot of fractal users start with Low and High cut in the cab block to limit what the virtual speaker produces to be more like the real world speaker before it goes anywhere else. If you create a preset from scratch I think the defaults are 20hz - 20khz for the cab block which is not what a real speaker would be at. I put a low cut at 100-120 hz and a high cut at around 8khz as a starting point. This will stop those high frequency tones getting past the cab block to your FRFR and causing issues with feedback maybe. Your most basic preset is AMP block and CAB block is another reason to put those cuts in the CAB block.
 
Total long-shot but did happen to me so just confirm....I once tried to power my wireless with a different power source for convenience and it turned out to be a mismatch. Unit worked but would feedback uncontrollably at stage volume. Could be worth confirming.
 
It shouldn't be the power source for my wireless. I haven't changed that out at all and it was the default power source that came with the unit. It was installed in my rack and hasn't been touched since. It certainly seems like I haven't done any of the default hi/low cut people are recommending to simulate a real guitar cab. I didn't know FRFR was so different compared to a real guitar cab.

You guys have given me a lot of information and tricks to try!
 
So a quick update: I found out that my digital wireless system has a gain boost and it was nearly +15db. I found that when I took it down to -25db, and set my noise gate to 0db, I removed the squeal. This seems to imply that my feedback is less the FRFR problem, and possibly a gain problem? If that's the case, I have another issue at hand.

Having my wireless receiver at -15db to have 0 squeal has effected the amount of "grit" in my dirty signal. Since I'm playing mostly old school Metallica, I really need that grit. I'm not sure if I should change amp model that has naturally more grit in it, or if there's another solution. Ideally, I'd like the wireless receiver at 0db gain to keep a more natural signal going to the Axe.

Also, does anyone have a good tutorial on how to use the PEQ? I tried using it last night to remove the squeal frequencies, but I think that block is a bit over my head in terms to understanding how to use it to hunt for and remove specific frequencies. The biggest problem is I don't know which frequency needs to be removed, and was hoping I could sorta..."find" it with the PEQ. If there's a way to do that, I couldn't figure it out.
 
So a quick update: I found out that my digital wireless system has a gain boost and it was nearly +15db. I found that when I took it down to -25db, and set my noise gate to 0db, I removed the squeal. This seems to imply that my feedback is less the FRFR problem, and possibly a gain problem? If that's the case, I have another issue at hand.

Having my wireless receiver at -15db to have 0 squeal has effected the amount of "grit" in my dirty signal. Since I'm playing mostly old school Metallica, I really need that grit. I'm not sure if I should change amp model that has naturally more grit in it, or if there's another solution. Ideally, I'd like the wireless receiver at 0db gain to keep a more natural signal going to the Axe.

Also, does anyone have a good tutorial on how to use the PEQ? I tried using it last night to remove the squeal frequencies, but I think that block is a bit over my head in terms to understanding how to use it to hunt for and remove specific frequencies. The biggest problem is I don't know which frequency needs to be removed, and was hoping I could sorta..."find" it with the PEQ. If there's a way to do that, I couldn't figure it out.
You may want to try getting your tone down with an old school cable first. Then bring wireless into the picture. It shouldn’t have an effect if set up properly.
 
You may want to try getting your tone down with an old school cable first. Then bring wireless into the picture. It shouldn’t have an effect if set up properly.

This is actually what I did do. I created the sound before I even had a wireless. Adding the wireless didn't have a major affect when playing in my rehearsal space, just the show. I could go back to the cable and see if there's anything different I guess.
 
Are you using a wireless guitar unit? Probably a long shot but my akg wireless unit gets a horrible squeal when its racked next to my furman. For some reason when the two were touching the squeal was terrible. I separated them by one rack space and the squeal was gone.
Just thought I'd throw that out there.
This is actually what I did do. I created the sound before I even had a wireless. Adding the wireless didn't have a major affect when playing in my rehearsal space, just the show. I could go back to the cable and see if there's anything different I guess.
Here is another interesting post re wireless squeal
 
Woah, I believe that's my exact setup. My Furman power conditioner is on top, followed by the wireless router, then the Axe, then the matrix amplifier at the bottom. I have more things to test now.

I did forget to mention that I did the high and low cut in the speaker block and that didn't help much, but I only did an 8k+ high frequency cut.

My next test is to get the squeal back, then use a Cable to see if the squeal is still there. I'm also going to move my power conditioner and see what happens.
 
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