How Do You Stop a Semi-Hollow or Hollowbody Guitar From Feeding Back?

Short version, because you probably came here mid-rehearsal with a howling ES-335: get off the amp, roll your guitar volume back to seven or eight, and pull a little gain off the amp. That combination fixes the majority of feedback complaints I see on the bench, and all three are free. If you play loud enough or dirty enough that those aren't sufficient, you move on to f-hole plugs and, in a specific case I'll explain, potting the pickups.

But before you touch anything, do the one step almost everybody skips: figure out which kind of feedback you actually have. Chasing the wrong one is the single most common reason people tell me "I tried everything and nothing worked."

First, name the noise

There are two completely different problems that both get called "feedback," and they have different cures.

Body howl is a low, blooming, almost musical tone that swells up when you're near the amp and sustaining a note or chord. That's the guitar's hollow body physically resonating in sympathy with the speaker. It's the classic hollowbody problem.

Microphonic squeal is different: a piercing, high-pitched shriek that can start on its own even when you're not playing, and gets worse with gain. That's usually a pickup whose windings have come loose and turned into a little microphone. It has nothing to do with the body being hollow — a solidbody can do it too — and stuffing the f-holes won't touch it.

If you can tell those two apart, you're already ahead of most players who bring me a "feedback problem." The rest of this article is mostly about body howl, with the pickup fix flagged where it belongs.

Why hollow and semi-hollow guitars howl in the first place

Here's the mechanism, because it tells you exactly what every fix is trying to do. Your speaker pushes air. That moving air hits the guitar's top and makes it vibrate. The pickup hears that vibration, sends it to the amp, and the amp pushes even more air at the top. Round and round it goes until the whole thing runs away into a howl. A solidbody barely participates because its top doesn't move much. A hollow guitar has a big, lightly braced top that moves a lot — so it feeds the loop.

This is also why "semi-hollow" and "fully hollow" behave so differently, and why it matters which one you own. When Gibson introduced the ES-335 in 1958, the fix was a solid maple block running down the center of the body under the pickups and bridge. The wings stay hollow for warmth, but the block anchors the top and hardware, so there's far less to set into motion. A fully hollow guitar — a Gibson ES-330 or its Epiphone cousin the Casino, both with no block and typically hotter P-90s — has no such anchor. Those are wonderful guitars, and among the most feedback-prone that come across the bench. That's not a defect; it's the design.

What actually works, roughly in order

Start free and reversible. Only get to the permanent stuff if you genuinely need it.

1. Get off the amp — distance and angle

This is the biggest lever you have and it costs nothing. Feedback falls off fast with distance, and it's much worse when the guitar's top faces the speaker head-on. Take two steps back and turn slightly so the body isn't square to the cabinet. Half the "my hollowbody is unusable" problems disappear right here. On a small stage where you can't move, at least angle the amp so it isn't blasting into the top.

2. Roll back your volume and tone a hair

Feedback lives at the extremes. Guitars are often set up to feed back the instant everything is dimed. Backing the guitar's volume off to seven or eight and rolling a touch of treble off the tone control tames most howl with very little audible loss — and it's instant. Learn where your particular guitar starts to complain and live just under it.

3. Tame the gain, keep the mids

More gain means more feedback, full stop. If you're getting into trouble with a dirty amp, pull the gain back a notch and lean on your picking for aggression instead. If you don't want to lose heaviness, try cutting a little low end on the amp rather than the mids — the boom is what excites the body, and the mids are where the guitar's character lives anyway.

4. Plug or stuff the f-holes

When the free fixes aren't enough for a loud stage, this is the real one. Fitted foam plugs made for f-holes — several companies sell them — drop in and out and noticeably cut the body's resonance. In a pinch, a rag or a bit of foam pushed inside the body does the same thing. You lose a little of the airy, acoustic bloom that made you want a hollowbody in the first place, so it's a trade, but it's reversible and it works. This is the standard move for players gigging a Casino or an ES-330 at volume.

5. Pot the pickups — but only if it's a squeal

This is the fix for that high, microphonic shriek, not for body howl. Wax-potting soaks the pickup's coils so the windings can't vibrate and act like a microphone. It's a common, affordable job and it's the right answer when a specific pickup starts squealing on its own at gain. It will do nothing for a resonating body, so don't spend the money here if what you actually have is a low bloom. (If squeal is your whole story, we go deeper in why your pickups squeal at high gain.)

6. A noise gate helps — but it is not a cure

People reach for a noise gate expecting it to kill feedback. It doesn't, and it's worth being clear about why: a gate silences the guitar when your signal drops below a threshold, so it cleans up the hum and squeal between notes. Once you're holding a note above that threshold, the gate is wide open and a howl will bloom right through it. Useful tool, wrong job if you're expecting it to save a sustained chord.

The honest part: some feedback is the point

I'd be doing you a disservice if I made it sound like the goal is zero feedback. Controlled feedback is one of the great voices of the hollow and semi-hollow guitar — that singing sustain that blooms when you lean into the amp is a feature players chase, not a bug. Kill it completely and you've killed some of the reason you bought the thing. The skill isn't eliminating feedback; it's moving the point where it happens so it's on tap when you want it and out of the way when you don't. Distance, volume knob, and where you stand are how you play that line in real time.

If you're shopping for a semi-hollow

Feedback behavior is a real buying consideration, and it's easy to check before you commit. If you play loud or with a lot of gain and you want the semi-hollow look and warmth without the fight, a center-block guitar — an ES-335, an ES-339, a PRS or Epiphone with a block — is the safer bet. If you're after that airy, acoustic-tinged jangle and you play at sane volumes, a fully hollow Casino or ES-330 is a joy and the feedback is manageable with the tricks above. Neither is "better." They're different tools.

When we take a semi-hollow or hollowbody in on trade, we note the construction and set it up so it behaves as well as its design allows. You can see what's on the bench right now in our guitars in stock, and if you're still weighing the formats, our take on solid vs. semi-hollow vs. hollow body and the Casino vs. ES-335 comparison both dig into how construction changes the way these guitars play and behave.

FAQ

Will stuffing the f-holes ruin my tone?

It changes it — you lose some of the open, acoustic bloom and the guitar leans a little closer to a solidbody. Most players find that acceptable for the amount of feedback relief they get, and because foam plugs come right back out, it costs you nothing to try and reverse.

Why does my ES-335 feed back way less than my friend's Casino at the same volume?

The ES-335 has a solid maple center block anchoring the top; the Casino is fully hollow with no block, and its P-90s tend to run hotter. Same volume, very different amount of top for the speaker to set in motion. It's the construction, not a fault in either guitar.

Does a thicker set of strings or lower action help with feedback?

Not really — feedback is driven by the body and pickups reacting to the amp, not by string gauge or action. Chase distance, volume, gain, and f-hole plugs first. A good setup makes the guitar easier to play, but it isn't a feedback fix.

Is a noise gate enough to gig a hollowbody with high gain?

On its own, no. It tidies up the noise between notes but won't stop a held note from howling. Pair it with f-hole plugs and some distance from the amp, and rely on your volume knob, if you're playing a hollowbody into real gain.