Jump to content

Pedal to Reduce Feedback?


Recommended Posts

  • Members

Hi guys, my brother just ought an Orange guitar amp half stack. It sounds amazing! But we are getting quite a bit of feedback with it on the distortion channel. What is the best and most effective way to reduce the feedback, without compromising tone? I'm open to pedal recommendation, or any other solution you think could work. Thanks in advance!

Link to comment
Share on other sites

  • Members

Short of turning down, the next option would be to move farther from the amp. Experiment with EQ. The tone controls on your amp might be enough or you might need to invest in an EQ pedal. What kind of guitar do you have? Solid body guitars like Les Pauls are less prone to feedback than semi hollowbodies like Casinos. Here's some reading for you: https://www.seymourduncan.com/blog/the-tone-garage/creative-solutions-to-control-feedback.

Link to comment
Share on other sites

  • Moderators

Feedback is happening to tell you something is wrong with how you are doing things...heed the feedback!

 

Easy answers....don't face the amp when playing, turn the guitar volume pots to about 7, turn the guitar tone knobs to about 7, ...there are so many variables...this is not a 'fix it with a box' thing, this is a 'learn your amp and your instrument' thing...also, half stacks are not good in small rooms with low ceilings....try it outdoors and see if it feeds back....when the cops come, be apologetic....:wave:

Link to comment
Share on other sites

  • Members

Thanks guys. So not a pedal solution if I’m understanding correctly. More of tweaking settings on amp and guitar then. We are in a small rehearsal room so I’m sure that plays a role. Will do some experimenting and see if that helps.

 

Also my friend with similar issue said he bought a limiter pedal and it seemed to help, not sure which limiter and open to opinions on this as a solution. Much appreciated.

Link to comment
Share on other sites

  • Members

Describe the kind of feedback. There are two main types. One is good and the other is typically good once its understood and controlled.

 

If its a whistling sound like you get from a microphone facing a speaker, and occurs even when you have the strings muted, then that's called Microphonic feedback. Pickups with metal covers usually do this. The steel cover acts like a microphone diaphragm and vibrates when in front of a speaker and sets up a feedback loop.

 

The fix for that is to have the pickups potted or have them replaced with better pickups. Some vintage pickups were designed back when people didn't crank amps up and get their unique sound from running on the edge of feeding back but those are the rare exception. You can use an EQ to minimize some of it like they do with a PA. You create narrow EQ cuts that match the feedback frequencies but it can wind up making a pickup sound awful when overused.

 

 

 

If the feedback is caused by allowing the strings to "Self Sustain" (the speakers make the guitar body vibrate, which makes the strings vibrate) this is called Syncopated Feedback/Vibration or self resonance. Its like yelling into the sound hole on an acoustic guitar then listening to the strings sustain afterwards.

 

This effects is Not a malfunction. Its in fact an effect most skilled guitarists learn to use quite effectively. They in fact seek out amps and guitars that produce these tones fluently. This kind or regenerating vibration can be used to create long string sustains and all kinds of string overtones to mix with the root note. Masters like Hendrix and Santana learned to control these sustains and turn them into an artform.

 

My guess is your brother hasn't used a loud amp before and hasn't developed a sense of "Magnetic Radar" yet.

 

That's what I used to envision it as being because it is kind of like using a radio antenna to tune in certain frequencies once the strings begin to self sustain. Its just acoustics but it does have a spatial aspect to it which you learn to manipulate as you around in front of an amp.

 

If you stand with your back to the amp and the guitar body blocked by your body, this is the "Null" point where the sympathetic feedback is minimized. Whenever I dial up my rock amps I make sure I have this "Null point when I'm positioned on stage in front of the mic so when I'm singing, I don't have strings sustaining out of control.

 

Then when I play leads, I should be able to step backwards towards my amp, and begin to generate self sustaining strings as soon as I turn and expose the guitar.

 

Example, Ever see guitarists do a power chord then turn the guitar so the neck points at you and the strings seem to sustain forever? What you thought was simply showmanship has an actual scientific basis which is being used.

 

If you turn left, the neck into the amp you can get different tones compared to the body being exposed.

 

Rarely do you actually face the amp (and turn your back on the audience) with the guitar. You risk causing microphonic feedback from the guitar even if you have potted pickups. Use a 45 degree angle when tweaking the amp. This is another null point because the heel of the guitar or tip of the neck doesn't have allot of surface for the speaker to strike.

 

Once the string sustain begins you can turn your body at different angles to the speaker and you'll hear the different 3rd's, 5th's 9th's and octaves come from the strings as the string nodes are excited and the string vibrations a divided.

 

Along with this sustain, hand and palm muting is essential in controlling the strings. typically you'll lay the right side of the right hand on the bridge where the strings meet up with the bridge saddles then roll it left to dampen the strings and roll it right to expose the strings and allow them to sustain. This is done at the same time as you pick the strings using a flat pick using your thumb and forefinger extended.

 

The result is a chugging chord that can be dampened between notes or allowed to sustain out of control as an effect. No pedal needed.

 

Along with that, playing leads consists of dampening all the strings except for the one you are currently playing.

It can include left and right hand dampening and using what's called pinch tones bounding the string off the thumb.

 

 

Like I said, these skills takes ears of practice to perfect and the only way you learn is but doing it.

 

I still remember the day I got my first decent amp as a kid. I waited till the folks were out and I could crank that thing up and was blown away by the tones I had only previously heard on albums. Within a few weeks I had learned how to control many of the tones and started putting them to good use with my scales playing leads and playing chords. Many professionals will actually mark out the stage using duct tape where they will stand to get specific tones when playing their guitars so they can reproduce the same tones captured on an album.

Link to comment
Share on other sites

  • Members
Thanks guys. So not a pedal solution if I’m understanding correctly. More of tweaking settings on amp and guitar then. We are in a small rehearsal room so I’m sure that plays a role. Will do some experimenting and see if that helps.

 

Also my friend with similar issue said he bought a limiter pedal and it seemed to help, not sure which limiter and open to opinions on this as a solution. Much appreciated.

A limiter would, well, "limit" the volume to a certain maximum so yeah, it would keep feedback in check. You can achieve pretty much the same effect by turning down. It sounds, though, like you're simply playing too loud for the room. Turn it down and the problem should go away.

Link to comment
Share on other sites

  • Members

A limiter would, well, "limit" the volume to a certain maximum so yeah, it would keep feedback in check. You can achieve pretty much the same effect by turning down. It sounds, though, like you're simply playing too loud for the room. Turn it down and the problem should go away.

 

Thank you, we’ll definitely try that. Now that I think of it, it may have been a noise suppressor pedal rather than a limiter that my friend has, not sure if that would make a difference? Either way, now I have some things to try thanks to you guys.

Link to comment
Share on other sites

  • Members

I'm guessing the OP is really having a problem with EMI hum and buzz which is typical and hard to avoid in "high gain" electric guitar amps.

 

Microphonic feedback is a high pitched "squeal" or "whistling" sound.

 

Guitar "string/pickup" acoustic feedback is more of a "howling" sound, lower-pitched than microphonic feedback, like Hendrix' 'Star Spangled Banner;

 

EMI (electro magnetic interference) comes from being surround by all the electric wires that power our modern world (and guitar amplifiers). You'll hear an annoying, steady hum or buzz that's there even with the strings muted, but the guitar's volume turned up. If that's your problem, your brother needs a "noise gate" pedal.

Link to comment
Share on other sites

  • Members

Get one of these into your chain. It may change your guitar sound somewhat but it does kill all the feedback.

 

[video=youtube;uomDSt3HaPA]

 

If your problems are at the same frequency all the time you can use a parametric EQ to notch that particular spot.

Link to comment
Share on other sites

  • Members
Is the feedback a squeal or a howl?

 

It's possible the guitar pickup is acting like a microphone.

I'd like to know too. I asked what kind of guitar the OP has, i.e., solid/semihollow body because the type of feedback will likely depend on the guitar. Unfortunately, we still don't have an answer. :(

Link to comment
Share on other sites

  • Moderators

okay, small room? TURN DOWN!

So now you are aware there are different kinds of 'feedback', as noted, but there are all sort of ways to prevent it, control it, or create it...and a limiter or a noise gate will NOT solve the problem, they will just make the guitar sound...well...worse.

So what;s the guitar, what are the pickups, what are the settings, how far away from the amp is he standing, which way is he facing....:wave:

Link to comment
Share on other sites

  • Members
okay, small room? TURN DOWN!

So now you are aware there are different kinds of 'feedback', as noted, but there are all sort of ways to prevent it, control it, or create it...and a limiter or a noise gate will NOT solve the problem, they will just make the guitar sound...well...worse.

So what;s the guitar, what are the settings, how far away from the amp is he standing, which way is he facing....:wave:

Indeed. So many questions, so few answers.

Link to comment
Share on other sites

  • Members
Get one of these into your chain. It may change your guitar sound somewhat but it does kill all the feedback.

 

[video=youtube;uomDSt3HaPA]

 

If your problems are at the same frequency all the time you can use a parametric EQ to notch that particular spot.

 

I have a Behringer 1124P Feedback Destroyer, but I use it for it's amazing 12 band Parametric Eq. Contrary to what some one posted, Behringer has made some great products over the years

 

The OP, should get a Rocktron Hush unit and put it the effects loop of the amp and that will nipp it the bud .... Just tweek it enough, so it won't cut off the signal too soon.

Link to comment
Share on other sites

  • Members

I use anti feedback in my PA rack but Guitar? Don't think so. It would be pretty useless

An anti Feedback unit creates narrow frequency cuts where the feedback frequencies occur.

 

I use a pair of Sabine 1020 Plus units in my PA rack. They way you use them is to set them for automatic scan mode then gradually turn up the mic to where it begins to feed back and the unit will set an EQ cut for the feedback frequency. It will set up to 15 of these cuts and then you can lock them in place.

 

Say you did that for a guitar holding a chord. The second you move or play a different chord, you'll create a whole different set of frequencies and overtones. The cuts you had set initially will be in the wrong places cutting the wrong frequencies.

 

Feedback suppressors like that Sabine and Behringer are all designed to run in a PA rack a Line level, not instrument level too. You'd have to preamplify the guitar signal up to line level to pass it through the unit loud enough to get it to operate then step it back down to instrument level to feed an amp. Wrong tool for the wrong job.

 

Someone mentioned a Hush pedal which is a triggered gate that might help. Again it depends on the actual problem happening. If the guitarist is getting his drive from drive channel of an amp them using a gate in the effects loop will be the most effective. You need it placed after the drive pedal to have the best string touch response. If they are using a pedal for drive you can place it after the drive before the amp. Some gate pedals like the Boss have a loop connection for placing your drive pedals. They are a little tricky to set up the attack and release times but they do work, especially for single coil pickups which develop allot of noise.

Link to comment
Share on other sites

  • Moderators

 

I have a Behringer 1124P Feedback Destroyer, but I use it for it's amazing 12 band Parametric Eq. Contrary to what some one posted, Behringer has made some great products over the years

 

The OP, should get a Rocktron Hush unit and put it the effects loop of the amp and that will nipp it the bud .... Just tweek it enough, so it won't cut off the signal too soon.

 

I am referring to their pedals, not their 'pro gear'. The pedals and other low end stuff [like their small mixers] work for a month or so, and then, in my experience, start having component and/or mechanical failures. I have been asked to 'repair' more inexpensive Behringer stuff than anything else, and I tell the owners it will cost more to fix than to replace the unit, but I advise them to buy a more reliable brand. I actually like their X32 mixers and some other products, like the 1124P, but they should have kept their brand names separate, like they do with the Bugera guitar amplifiers.

Link to comment
Share on other sites

  • 5 weeks later...
  • Members

I like feedback when it's good.  So in the sense of good feedback and you wanting a pedal to control it I recommend a volume pedal.  Now, you don't have to like Ted Nugent, but he is the master at utilizing and control feedback with a hollow body guitar and he does so with the volume knob.  Check him out for some ideas.  

 

Link to comment
Share on other sites

  • Members

It's early in the morning here in Thailand, so don't get on my case too much puh-leeze...

How about an acoustic processor in the chain? I have a cheap old Zoom A2 and couple features include feedback surpression (a notch filter, can be automatic) and I wonder if phase reversal would have any effect on cutting down feedback. Have used it a few times with electric gits: no distortion settings (duh) but the other features can yield interesting results.....

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...