live feedback

[jammin jay]

Hey All
Our folk rock band has been playing larger (and louder) venues. I use a sound hole cover (and we use IEMs, not floor monitors), yet still get feedback. My Yamaha's electronics features an anti-feedback control which finds and dampens the culprit frequency; however, this just changes the tone.
Am I missing something obvious here?
How is it that stadium rockers can do acoustic numbers without feedback?
Your suggestions are appreciated!

[YamahaGuy]

Can you give us an idea of your setup, i.e. what kinds of mics you're using, where the FOH speakers are, where you are relative to the drummer, if your drummer is using an electronic kit or an acoustic kit. Is the drummer loud? Are the drums mic'd? The large venues usually have the front of house speakers a really far way away from the performers. If you're close to high "horsepower" front of house speakers, or your drummer is loud, you're close to them and so your mic and guitar need to be pushed hard to overpower the drums, that would be the likely culprit in my book. Amps for bass and guitar are also another factor. Are they standalone or are they mic'd and/or lined into the PA? Lots of factors.

No disrespect to drums, but they're public enemy no. 1 in live sound mixing. You'll notice in large venues they're high above and relatively far away from the acoustic guitar player and singers. In church settings the drummer is put into a fish tank LOL.

Proximity to the front of house speakers and/or gain on your vocal mic and guitar are (in my experience) the main things that will cause feedback issues.

[RussellHawaii]

I think at the stadium rocker level, you’d use a magnetic sound hole pickup, which won’t feedback. Also, you’ll see a lot of smaller bodied stage guitars, which are less prone to feedback.
For regular pickups, feedback buster sound hole insert, notch filter, phase switch, and anti-feedback eq-ing help a lot. Lots of low end EQ reduction, especially in the monitors.
Speaker placement is the most critical thing…not pointed at the face of the acoustic.

[shufflebeat]

A feedback loop is a very simple system and breaking it is theoretically very easy, balancing the outcomes is where it gets complicated.

It would be useful to consider what role the guitar plays in the overall sound and how that relates to what you need/want to hear.

Often in a “full” drum/bass setup the acoustic guitar is a rhythmic element, tuned percussion rather than mainly melodic like fiddles, accordions and singers.

If this is the case then you’re complementing the bass and there’s no real need for the most feedback-prone regions of the spectrum. A simple HPF at 150Hz will remove a world of pain at a stroke. If you actually need to hear a fuller sound then a pre-EQ feed to IEMs will retain what you need.

“Doing” sound is as much about decisions you make before you walk onstage as it is tweaking the knobs when you get there.

[ljguitar]

Originally Posted by jammin jay

Hey All
Our folk rock band has been playing larger (and louder) venues. I use a sound hole cover (and we use IEMs, not floor monitors), yet still get feedback. My Yamaha's electronics features an anti-feedback control which finds and dampens the culprit frequency; however, this just changes the tone.
Am I missing something obvious here?
How is it that stadium rockers can do acoustic numbers without feedback?
Your suggestions are appreciated!

Hi Jay and welcome to the forum
If we know what your gear consists of, and what you are playing it through it will help us know what advice to give.

Also are you playing through and amp, or PA? How experienced are the Sound Techs or are you setting up your own gear and adjusting it yourself?

And the way 'rockers' get results is with proper gear, proper setup, and great sound techs who know how to dial in the sound. Even our moderate digital board at our church has a Behringer X32 mixer which offers 6 points of parametric-EQ which is more than adequate to control this.

I have seen one rock band in the area where the lead singer plays wild-acoustic and his rig is an old Alvarez with a magnetic in-hole pickup through a direct box and straight into the 'snake'. He can match their electric lead player for volume. It's not pretty sounding but he doesn't wrestle with feed back with his monitor 2 feet in front of him. He also runs the band, and gets to choose which guitar is loudest (his).

[conecaster]

Originally Posted by YamahaGuy

Can you give us an idea of your setup, i.e. what kinds of mics you're using, where the FOH speakers are, where you are relative to the drummer, if your drummer is using an electronic kit or an acoustic kit. Is the drummer loud? Are the drums mic'd? The large venues usually have the front of house speakers a really far way away from the performers. If you're close to high "horsepower" front of house speakers, or your drummer is loud, you're close to them and so your mic and guitar need to be pushed hard to overpower the drums, that would be the likely culprit in my book. Amps for bass and guitar are also another factor. Are they standalone or are they mic'd and/or lined into the PA? Lots of factors.

No disrespect to drums, but they're public enemy no. 1 in live sound mixing. You'll notice in large venues they're high above and relatively far away from the acoustic guitar player and singers. In church settings the drummer is put into a fish tank LOL.

Proximity to the front of house speakers and/or gain on your vocal mic and guitar are (in my experience) the main things that will cause feedback issues.

If we keep doing the same things we keep getting the same results.

Contact transducers

Internal or sound hole mounted mics

Coil mounted sound hole pickups

Under saddle transducers.

At high vol all will cycle.




Is this guitarist struggling with feedback?

With a sax right in the face of the guitar, a fully acoustic guitar I made him with our amplification system, a 100 watt JC 120 behind him and drum kit right there. The top of that guitar is no more that .095 thick. A steel string top would be .115 to .125 in most cases

I have spent half of my 48 years making guitars achieving these results. Putting guitars out front as feature instruments on loud stages.

You do not get here with the standard concepts that are all proven feedback devices.

There are better concepts.

[YamahaGuy]

Originally Posted by conecaster

If we keep doing the same things we keep getting the same results.

Contact transducers

Internal or sound hole mounted mics

Coil mounted sound hole pickups

Under saddle transducers.

At high vol all will cycle.




Is this guitarist struggling with feedback?

With a sax right in the face of the guitar, a fully acoustic guitar I made him with our amplification system, a 100 watt JC 120 behind him and drum kit right there. The top of that guitar is no more that .095 thick. A steel string top would be .115 to .125 in most cases

I have spent half of my 48 years making guitars achieving these results. Putting guitars out front as feature instruments on loud stages.

You do not get here with the standard concepts that are all proven feedback devices.

There are better concepts.

I have no clue what you're trying to tell us.
The drummer is not playing loudly as a rock drummer would., the drums are elevated and very well mic'd, and the guitar player is no where near the FOH. I see some side fill speakers 30' away.

Good job making the guitar for the guy.

[Nymuso]

Jammin' Jay are you going DI to the board or are you playing into an on-stage amp?

[conecaster]

Originally Posted by YamahaGuy

I have no clue what you're trying to tell us.
The drummer is not playing loudly as a rock drummer would., the drums are elevated and very well mic'd, and the guitar player is no where near the FOH. I see some side fill speakers 30' away.

Good job making the guitar for the guy.

I could turn that around?

Are you trying to say that I do not understand the stage conditions?

The reason the JC 120 is there is because Peter wants the front row to hear him. He is in the amplitude of that thing and its cranked. The speakers you refer too are so far outside and blasting past the front seats.

This is an artist who could have any product for free. He would rather pay to get his sound. 25 years ago he was playing an ovation stuffed with T shirts. He tours with nothing to run his guitar through.


The sax is blowing right at the guitar. Try that with a top mounted transducer or under saddle.

This drummer is not as loud as his usual drummer, Eric Valentine, whom I have seen behind him many times, Eric is Lukather's drummer, he is a monster.

My point to you is, I can not provide Feedback resistance with standard concepts as defined above. I have 25 years putting high vol. Stage instruments on stages. You either do it in the guitar or deal with it outside the guitar.

I know the economics of what these products are from my interactions with the manufacturers.

Players are evaluating sound, manufacturers are evaluating price points. There are a few exceptions to this rule. Godin broke the price point when they used RMC, that is not a part made in China for $10 or less.

Tell me what the price point is that guitar manufacturers generally are willing to pay for a pickup system?

So if you sound evaluate a price point are you evaluating what is possible?

This thread is about feed back resistance.

Here is a close quarters demonstration between a popular under saddle and the system in that guitar on stage above.

I can assure you if you use an under saddle or top mounted transducer you will have no better results that is demonstrated here. I had nothing to do with this video, this is a sound guy who owns a studio. He wanted to test our claim of feedback resistance.

[SpruceTop]

Paul, does your GO Acoustic pickup sense both string and top/body vibrations?

[conecaster]

Originally Posted by SpruceTop

Paul, does your GO Acoustic pickup sense both string and top/body vibrations?

The pickup does not transmit the top much but the strings are a reflection of the top so it is still able to capture the tonality of the top.

Back on 2019 we were discussing systems with Cordoba. They wanted tap sensitivity for flamenco players. The microphone was added to provide top Signal to be mixed with the pickup.

Initially the mike was mixed to be very low signal. But people wanted more of mike, the pick up signal was reduced so the mike could be louder in the mix.

This runs against the primary purpose of feedback resistance. The mike its phased against 3 strings to help prevent feedback, but a Mike its a vocal character.

So, if you want ultimate feedback resistance turn the mike down as you raise vol.

If you notice on the video, Neale's voice was drawing feedback either by exciting the strings or the mike was on a bit.

If you notice in the Peter White video he takes his hands off the strings and the sax is right there. I do not make guitars that are anything but fully acoustic. That instrument is absorbing a lot of ambient energy.

Peter's guitar is more feedback resistant as it has individual saddles for each string which reduces cross over between string's energy. The GoAA preamp , my amazing partner designed, separates string energy but the physical separation enhances the effect.

Putting a plug in the sound hole suppresses cavity resonance. We do not really find that an issue with our system.

A shout out to Yamaha Guy

Nice to have a good conversation via messaging

Passions runs deep but so does quality, he is a quality guy and I appreciate him very much.

[jammin jay]

Thanks to all who replied; much appreciated. I play a Yamaha A5cM, which is a deep bodied guitar. The electronics will filter for feedback frequencies, and I use the included soundhole cover. I play through a Fractal FM9 and direct out to PA. I avoid floor monitors and use IEMs. Obviously, I am getting the worse feedback when close enough to house mains/subs (whether they are beside, in front, or above me). At this point, I will try to stay farther back on stage. However, I will research magnetic sound hole covers. Thanks again, All.