Sound hole cover designs - vented, modified or otherwise

[000M]

Has anyone experimented with different sound hole cover designs/mods to find your sweet spot between tone and feedback suppression?

My Feedback Buster was a super tight fit and made my guitar sound like it was singing through its nose, so I cut a very small piece of pie out of it with an exacto-knife. It seems to have helped the tone as well as the fit.

Keen to hear if you've explored different designs, eg. the Dean Markley/Dunlop vented suppressors, Lute Hole, other designs, any diy modifications.

[jseth]

I wouldn't say I have "experimented" with sound hole covers, but I have one of the first Lute-Hole designs, and when I lived in Fort Bragg, Ca., I had the chance to check out the Planet Waves "O-Port", as James Goodall had received one as a "test it out" sample...

Truth is, I wouldn't want either of these things in any of my guitars. There's a reason that soundhole is there, and blocking it, in any shape or form, is going to diminish tone and volume...

I think the best defense with on-stage feedback is positioning monitors/performer and some seriously good EQ, coupled with an EXCELLENT pickup system. I don't care what you use to dampen feedback tendencies, if the pickup isn't a really good one (or you're attempting to use it in an "extreme" situation, i.e. a loud band on a smallish stage), you ARE going to get feedback...

Curious that cheaper instruments made with laminate wood can sound really good fairly easily, when amplified. That sort of "dead" quality to a less-expensive instrument turns out to be quite a bonus when you're amplifying it.

Sorry I couldn't help more...

[Eric_M]

Originally Posted by jseth

here's a reason that soundhole is there, and blocking it, in any shape or form, is going to diminish tone and volume...

It undoubtedly does; when I put in my old-school black-rubber feedback buster, the guitar does get nasal, as 000M put it, and muffled.

Do you hear a difference when amplifying, though? Can't say I do. And in situations like open mics where there's not much time to attend to sound issues, I have found that plugging the soundhole pretty much always works. And as you say, that "deadening" can be an asset when amplifying. To my ears at least it doesn't hurt things.

And of course I don't leave it in when I'm playing acoustically.

[Stratcat77]

I use the old standard rubber hole blocker - always have. I therefore dialed in my tone using my Baggs Venue preamp with the hole cover in and I get lots of compliments from other players on my live sound. Oh, and I never ever get feedback.

When I'm at home unplugged, I see no need for a hole cover and don't.

[ljguitar]

Originally Posted by 000M

Has anyone experimented with different sound hole cover designs/mods to find your sweet spot between tone and feedback suppression?

My Feedback Buster was a super tight fit and made my guitar sound like it was singing through its nose, so I cut a very small piece of pie out of it with an exacto-knife. It seems to have helped the tone as well as the fit.

Keen to hear if you've explored different designs, eg. the Dean Markley/Dunlop vented suppressors, Lute Hole, other designs, any diy modifications.

Hi ooom

Having started amplifying acoustic guitars in the 1970s on aggressive stages, I have a lot of experience with feedback suppression and blocking the sound hole of instruments.

These days (and for the past 15 years) I own two Lute Hole Covers and a Big-Black-Plug for my three main acoustic guitars, and they are equal in feedback prevention on loud stages where the sub-woofers or floor monitors are being pushed very hard.

Interesting side-note - all my systems are dual source with a pickup and an internal mic, and I have to reverse phase on the mic when the feedback-suppressor is in. It's the only side-effect of using one with my dual-source systems. Only the mic is affected, and when phase is reversed the sound/tone/everything is restored to the same sound I get with no suppressor in.

Too much volume from, or too close of proximity to, sub-woofers will trigger feedback in any of my acoustics. If I had time and if the sound tech had the know-how, it could be tuned out. But if you have ever played in a busy venue with short sound checks, and semi-engaged sound techs, you know it's going to be an issue that a feed-back-buster of any type will fix in three seconds.

I was pleasantly surprised with both the medium and light versions of my Lute Hole covers (which I've had for over 15 years now), since they do allow a bit more acoustic sound into the room, and they block feedback EQUALLY with the Black-Plug (not a brand name - just the big-black-rubber-stopper which fits a sound hole).

I have the Lute Hole covers because they are classier looking at weddings and funerals than the Black-Plug, and they work equally well.

Blond for Spruce Top…mine has the edge sanded out to accomodate the end of the fingerboard which extends into the sound-hole…


Darker for dark tops…


The Big-Black-Plug is just that. It's big, it's thick, it blocks feedback. I had a Baggs Dual Source with sound hole controls at one point in my main guitar, so I took metal-shears and chopped a section out just big enough for me to operate the volume controls, and it did not increase the feedback at all. Interestingly, my mini-Jumbo has a side port which doesn't affect feedback at all.

Soundholes don't have to be hermetically sealed, nor water-tight, to block feedback. James Taylor (back in the 1970s) used to tape a Shure SM-11 lavaliere mic inside his guitar, and then tape 4X6 Note cards over the sound hole to cut feedback and it worked well.

Hope this adds to the discussion…

[000M]

Helpful stuff all round! Thanks everyone for taking the question seriously and giving useful answers - I was expecting a bit of backlash if I'm honest.

@ljguitar Really interesting that the Lute Holes and big black bung get the same result. How do you think the Lute Hole works? Does it dampen the top a bit?

[Guitarplayer_PR]

Originally Posted by 000M

Helpful stuff all round! Thanks everyone for taking the question seriously and giving useful answers - I was expecting a bit of backlash if I'm honest.

@ljguitar Really interesting that the Lute Holes and big black bung get the same result. How do you think the Lute Hole works? Does it dampen the top a bit?

It certainly dampens it much less than the Feedback Buster. To my ears, it compresses the tone just a bit.

[varmonter]

When i first got my Kand K martin d28s.
I had a heck of a time getting it to not howl
when the volume was turned up a bit.
I bought the rubber plug and sure acoustically
it was approaching the sound of a strat unplugged.
I tried the lute hole and it looked nicer and acoustically
was a bit better. Both sounded the same plugged
in. ( guitar sounds the same plugged in with or without)
Both stopped the howling.I have since purchased better outboard gear
and have no need to use either in years.
Like said above judicious eq and monitor positioning
can do wonders ..Also look at why you need to
be that loud. Drummer and electric instruments
can not be competed with. If they won't tone it down
you might consider buying a tele. or an emerald
or crowdster type of acoustic. I have a lute hole
i sell you cheap ., pm me.

as far as how they work .. I think they prevent
external sound from entering the body of the guitar. thru the soundhole.
Which is what starts the feedback loop to begin with.