Archtop Feedback

[Bluesboybob]

also check out F Hole Covers | F-its Feedback blockers|Double bass feedback|

[cosmic gumbo]

I fixed my archtop feedback problem quite successfully, it's called telecaster.

[Little Jay]

I don’t have to deal with feedback in my archtops (ES-125, Furch G-100 and a Japanese ES-175) because I put sound posts in them. Bye bye feedback.

[TACKEY]

Hi,

I have a 17 jazz Tanglewood archtop guitar. It's not my high-end guitar, but I love the action.

I play in a 12 by 10 room, use a Vox Valvetronix amp, but get a lot of feedback.

Any ideas on how to fix this?

[Ray175]

Traditional solutions include :

• place your body between the amp and the guitar (if seated)
• stuff foam inside the guitar via the F holes
• use f-hole covers (Doug's Plugs)
• adjust the eq profile of your sound to redce resonance effects, using a decent parametric eq pedal
• cut bass levels on the amp
• ...

[oldane]

Some amps are equipped with a low cut (= high pass) filter for the (main) purpose of removing low frequency boom. Acoustic Image is one, but there are likely others. Such low cut filters also come in pedal incarnations and if it's just boom/low frequency feedback you want to get rid of, they are easier to use than a parametric EQ unit. The idea is to "turn up" the adjustment knob (adjusts the frequency at which the cut off sets in) just about enough to dampen the annoying boom satisfactory. You will have to accept sacrifying the lowest frequencies but IMHO boom and/or feedback is far worse. Of course higher frequency feed back can't be removed with a low cut filter but needs a proper parametric EQ - but then it's the low frequency boom/feedback which is the main problem in small rooms.

Open back cabinets seems more prone to boom and feedback in small rooms than closed back cabinets. The same goes for bigger speakers as compared to smaller speakers. Back in the 1990s I bought an Evans amp with a 12" speaker. It was a very nice amp but it boomed easily when practicing in my living room which I lived with for some years. Eventually, I replaced it with an Acoustic Image head and a Redstone 10" closed back speaker cabinet. Problem solved (though I felt a need to add a Sansamp Paradriver DI for satisfactory tone shaping). Later I added the very small and portable Mambo 8 Wedge which may be even better suited for small rooms than the AI/Redstone combo - though my age related treble hearing loss may contribute to me having that impression. Halfway OT, I may add that the Redstone speaker cabinet also works well and without boom in my living room with a Quilter Tone Block 202 I bought recently, provided the bass is turned down to about 9 o'clock.

The placement of the amp/speaker is also important. Placing it in a corner will increase the risk of boom and feedback. Raising it up from the floor or tilting it will reduce the low frequencies and will thus reduce the risk of boom/feedback.

Naked rooms without carpets, curtains and book shelves is more prone to boom/feedback than furnished room with carpets, curtains etc. OTOH, heavily furnished rooms can dampen the sound so it seems lifeless. A small and well controlled amount of room reverberation adds to the impression of fullness of sound. We guitarists can to a certain degree replace that room reverberation with the artificial reverb on our amps. Wind players sometimes like to practice facing a wall. When I played saxophone many years ago, I often did that and always felt the tone got bigger and fuller to my ears because of the sound reflected back from the wall.

[Thumpalumpacus]

Stand off-axis from the speaker with pickup(s) pointed away, use lower volumes, or get a parametric EQ and see if you can zap it that way.

[christianm77]

- Roll off the bass
- point speaker away from guitar
- lean on the amp less for your tone (i.e. pick more firmly.)

[Hammertone]

...adjust the eq profile of your sound to redce resonance effects, using a decent parametric eq pedal...

Some amps are equipped with a low cut (= high pass) filter for the (main) purpose of removing low frequency boom. Acoustic Image is one, but there are likely others. Such low cut filters also come in pedal incarnations and if it's just boom/low frequency feedback you want to get rid of, they are easier to use than a parametric EQ unit. The idea is to "turn up" the adjustment knob (adjusts the frequency at which the cut off sets in) just about enough to dampen the annoying boom satisfactory. You will have to accept sacrifying the lowest frequencies but IMHO boom and/or feedback is far worse. Of course higher frequency feed back can't be removed with a low cut filter but needs a proper parametric EQ - but then it's the low frequency boom/feedback which is the main problem in small rooms provided the bass is turned down to about 9 o'clock.

This portable EQ box from Carl Martin works well for adjusting sound to minimize feedback between a nice electrified archtop guitar and a decent combo amp. Good for upright bass as well. It can also be used as a straight boost, which is very useful. Also good for dialing the quack out of flattop guitars with piezo pickups, but I don't have experience with that. It's been available for years. Up until @2016, it was AC powered - that's the version I have. More recent versions use a wall wart. I think Carl Martin may have stopped advertising it, but it's around. Not cheap, but high quality. Various other companies, like Fishman, make similar portable pedal-based EQ products. Probably lots of cheapo MIC options available as well these days.

[Little Jay]

If you only play the guitar amplified: put a sound post under the bridge. Acoustic volume will decrease somewhat, but in my ES-125 I did not notice any change in amplified sound. But feedback is almost gone.

Btw, my ES-125 is still susceptible to the height of the polepieces, especially on the bass side of the pickup: when I put them too high I will have feedback when I stand next to the amp on a loud stage (my amp is always elevated to about hip-height). Just one twist down and it’s gone. I don’t know if that’s specific for P90 pickups, I have not experienced that with humbuckers on my other guitars.

Oh and a sound post is completely reversible and non-invasive, so if you don’t like it, just take it out again.