Musician Gear & Tech Discussion

Does anyone have a secret for eliminating or reducing the feedback when playing a hollowbody electric??? I have an awesome sounding '66 Hagstrom Viking, very similar to a 335...I play through a Blues DeVille Reissue with the Master usually less than 3. But about the only way I can even remotely control the feedback is by turning down the tone controls on the guitar, which ruins the great sound it has....Moving away from the amp or off to the side helps a little in certain conditions, but then I pick up the bass player,or the other guitarist amps...Any help or ideas???

Try an eq and cutting everything above 3k since an amplified guitar does not put out any frequncy above this. Well technically 3.1k or so.

What I found since I have had the same problem is that because a lower frequency is boosted a higher frequency is as well to make up for it and this causes the feedback. By cutting the lower, you can also cut the higher and thus solve the problem, and not impact the sound. It's tedious, but in desperation may be worth the trouble.

This is a long shot and may or may not work for you. Some guitars just like to feed back because of the pickups, construction etc. but eq-ing has worked for me.

I used to play a hollow-body Mosrite (until the frets wore down to the fretboard).
I've tried several filters, but didn't like the loss of harmonics.
What I finally did was just to pivot my entire body/guitar 90 degrees one way or the other, untill the feed back went away. Keep pointing the neck up and down, lean forward & back - there's almost always a spot where the feedback disappears.
Of course, when performing in front of an audience, that's not always so convenient, is it?
.
I play an acoustic guitar, now, with a built-in pickup. . . . not quite the same as a hollow-body electric, but with similar feedback problems.
I boucht an amp with a built-in 'feedback notch-filter."
You're probably familiar with it; but, if not: it's a dial which attenuates the volume at just one part of the guitar's sound spectrum. You just turn the dial until the feedback goes away.
It usually works great, but sometimes the feedback just appears in another range.
If that happens, what I do is to tune the feedback notch-filter to the same key as the song.
That is, for example, if a song has a real lot of "D' in it, I turn the dial so the feedback appears in 'D'. Then if it feeds back, it sounds like part of the song.
If the feedback gets overpowering, I know I can instantly stop it by gently touching the D string or whichever "D" is appearing in the currently-played chord.
Or 'A,' or "C," - wherever you've tuned it.
.
Someone has to be selling a separate notch filter, somewhere.
Hope this helps

Thanks guys...I'll have to see what I can do about trying some kind of an EQ. But I don't want to ruin the really cool tone of that guitar...I still believe there is some kind of trick out there the "pros" use, because an awful lot of "pros" play hollowbodies without the screaming feedback that I get....But I will surely try your suggestions, THANKS!!!

I know this post is a week or two old, but I missed it for some reason...

BB King used to stuff his 335 with cotton to stop feedback. He plays a solid body now, for that reason.

I've played a 335 through a 120watt Peavey Butcher full stack many times, and with a loud band, no feedback problems at all. None. I wa samazed, but the thing never had any problems. I coul dget feedback if I wanted it, but it never just insisted on feedback the way some of them do. I now play a Cort CL 1500 hollow body through a Fender Super Reverb (45 watts) and Peavey MX (130 watts) dual amp rig and no feedback at all unless I cause it intentionally.

I would try setting up the amp in different positions in relation to your stage position, pointing it slightly to the side or tilting it upward, try an amp stand...

I'm also wondering if the pickups might be microphonic. That will cause uncontrollable feedback in any guitar, solid body included. The bride pickup in one of my telecaster copies was microphonic, instant really loud feedback any time I was not touching the strings. Took a bit of looking, but I found out potting it cures this.

Not difficult to do, you basically dip the pickup in melted wax until it stops bubbling, let it cool and clean it up, being very careful not to touch the windings. I use a small picture wire to hang the pickup, not the connecting wires, to avoid damaging them. A small potpourri pot works great to melt the wax in.

Stewmac has good instructions.

One other thing . . .
If you use an acoustic guitar w/ a built-in pickup (as opposed to what is termed a 'hollow-body electic'), I've heard that you can buy a rubber plug that goes right into the sound hole.
.
Remember, what ultimately causes feedback is the strings vibrating at the same frequency as the speakers. I know this is basic stuff, but bear with me; - often answers are found by thinking about what you already know . . .
Feedback w/ hollow body or acoustic guitars . . .
In this case, an acoustic guitar will work backwards.
Normally the strings vibrate and the whole top of the guitar vibrates (intentionally, by design) along with the strings. That's why acoustic guitars often have more flexible wood on top than on the sides. For example, you could have a guitar with mahogany sides and a pine top.
The top vibrates & emits sound in both directions.
1/2 of the sound bounces off the bottom of the guitar, on the inside, and some of this sound comes out the sound hole. And that can help the strings vibrate more, too.
OK.
If you play your acoustic, and if you don't touch the top of the guitar at all, it will be louder. Put your forearm or edge of your palm against it, and it's a bit softer.
That is: deaden the top and deaden the sound.
Anything that helps stop the top from vibrating might help decrease feedback, in some situations . . .
I'll admit, this hasn't worked for me - most of my feedback was from the sound coming from the speaker to the strings . . .
Anything that cuts down on sound coming out of the sound hole could possibly help to decrease feedback . . . in theory . . .
Or not . . . I just want to get people to visualize what's happening . . . .
.
OK, now here's another thought:
I don't know about your guitar, but I can remove the plastic saddle which sits over the pickups.
For those who are unfamiliar: the saddle is the strings rest on. . .
I originally removed the saddle to shave it down, to lower the strings and improve the action. Works great, by the way.
I had a 2nd, brand new saddle all set, in case I took it down too far.
OK, next I made several 'shims' made out of paper, and cardboard. I've used various combinations of shims to raise and lower the strings. It's not much, but I can feel the difference between 1 and 2 paper thicknesses, if I use the same set of strings again.
With my last set of strings I use 3 shims. The current set: just one; and I can probably remove that without the strings buzzing . . .
.
I'm digressing . . . senility . . .
.
ANYway: the feedback is caused by too much sound getting into this pickup.
I don't know what % of the feedback is from the top, and what percentage (most of it) is from the strings.
But: it sure is food for thought . . .
You migh say 'oh, no; that won't work . . .' or 'hmmmm . . ." But - either way, I've got you thinking about it. And so - you just might come up with something, eh?

Be creative.
One warning. If you can remove the saddle, and if you decide to sand down the bottom of it to lower the action: have a new replacement on hand. If you go too low, you'll be sorry . . .
I've got to say, though: putting cotton inside is a simple and elequent solution to almost everything I mentioned . . .
It's 1/2 way between solid-body to hard body.
Hmmm . . . so BB King used to play a 'cotton-body' guitar, eh?

Yep, the 335 hollowbody style guitars he prefers are notorious for feedback problems at high volumes, so he would stuff them full of cotton to cut down the feedback. He finally got together with Gibson and had a solid body made, identical guitar but solid body.

OK I looked up a link and have to correct myself, it's a semi holow body with no sound holes, I thought it was a solid body, just looking at it when I saw BB King last year at his Indianola, Miss. birthday festival. He's 83 now I think...and still playing over 200 gigs a year. Here's the Gibson write up about it.

And he's always named all his guitars Lucille. There's a story about that too...Bar he was playing in caught fire, BB ran back in to grab his guitar, if I remember correctly a $35 acoustic, and later found out the fire started by way of a fight between two guys over a woman named Lucille. I think they knocked a candle off a table...He named his guitars Lucille after that to remind himself to never do anything that dumb again.

One other thing, I'm wondering if the amp Guitarzan uses is tubes or solid state. It seems solid state tries to feedback more than tubes with this style guitar. I know I use two tube amps, Fender Super Reverb and Peavey MX, and when I used a friend's Oscar Schmidt 335 copy it didn't feedback onstage at all.

Hey Thanks for all the advice!!!! Most of the tricks that are discribed, I've already tried....BTW, I am playing a "Blues DeVille Re-issue" 60W Tubes, 4-10's....on an angled stand (to reduce the over-all volume for the rest of the band)(it's LOUD!!!!) Anyway, a few weeks ago, I replaced the output tubes with "Groove Tube Substi-tubes" which made the amp run in Class A, and effectively lowered the output wattage to 25W...Guess what??? It's STILL loud!!!! I asked tech support at Groove Tubes why and found that even cutting the output by 50% only reduces the output by 3 Db....I should have remembered that from Electronics school....Anyway, as long as I don't use my "Big Muff" for distortion, it's a little easier to control the feedback...Still, I wish I could trust it, It's an AWESOME guitar, but takes off like an f-14 sometimes!!!! ROCK ON!!!!

Did you give serious consideration to the possibility of microphonic pickups? I'm wondering because especially on older guitars it can be a problem once everyhting vibrates for a few years and generally gets loose. The combination of hollow body guitar and microphonic pickups would add up to Ted Nugent on a really bad night...

Does any other guitar feedback on your amp? Can you get a newer hollow body to try briefly and see if it's as bad?

I'm also wondering of the amp might need a bit of a tune up. I never get any feedback at all out of my Super Reverb (45 watt tube 4x10) even if I put the guitar a foot on front of it, except with the hollow body Cort, and then it's not loud, screaming uncontrollable feedback, it's the kind of harmonic feedback I can play with and get it to do what I want it to do. Same for a friend's 335 copy.