Boomy Stages

[Chienmortbb]

Has anyone a solution to boomy stages. I have thought of using some 50 mm foam, but will that solve it? I have another gig there on NYE.

[fretmeister]

High Pass filter and also EQ to suit the room even if it's a bit bass-light.

[Chienmortbb]

19 minutes ago, fretmeister said:

High Pass filter and also EQ to suit the room even if it's a bit bass-light.

A thought occurred to me that there is terra firma at the side of the stage, so I might put my LFSys cab there and use a smaller amp/IEM for on-stage monitoring,

[fretmeister]

Will probably help quite a bit.

 

I do a couple of gigs a year at a place that has an awful folding stage. Sometimes I've pretty much Zero'd the bass knob on my amp to deal with it.

[BigRedX]

No backline, everything through the PA and IEMs for the band.

[Bill Fitzmaurice]

Isolation devices have no effect, because the boom isn't caused by mechanical conduction between the cab and stage, it's caused by the resonance of the space beneath the floor/stage and room modes.

https://www.bassgearmag.com/submit-article-bass-amplifier-isolation/

http://ethanwiner.com/speaker_isolation.htm

One potential fix is to lift the cab a meter or so off the floor, which works as an acoustical notch filter. A full parametric EQ works best, allowing you to dial out the boom frequency. If the cause is the stage it tends to be one frequency, as the space below has only one resonant frequency. High pass filters can tame the boom, but they also tame the frequencies  below the boom frequency, which tends to be in the 100-200Hz octave.

Edited October 12, 2022 by Bill Fitzmaurice

[chris_b]

One stage I play on has bare brick walls and a concrete floor and ceiling.  There is a bad boom in the corner.

 

I fixed that by placing the cab a couple of meters away from the corner. It's still a terrible sound but there's no boom.

[walshy]

I use a Gramma Pad, it’s excellent and not had any issues on boomy wooden stages since. For the money they’re excellent and super well built too. 

[hiram.k.hackenbacker]

1 hour ago, walshy said:

I use a Gramma Pad, it’s excellent and not had any issues on boomy wooden stages since. For the money they’re excellent and super well built too. 

+1 for Gramma Pad. Used it for years on a hundreds of stages = zero issues.

[la bam]

Could you just use IEMs?

[fretmeister]

9 hours ago, la bam said:

Could you just use IEMs?

 

He doesn't say whether the bass is in the PA or not.

[Chienmortbb]

Just now, fretmeister said:

 

He doesn't say whether the bass is in the PA or not.

It was not in the PA, but I was thinking of using IEMs myself at that gig which would entail taking everything through the PA. That can be done. We usually use the singer's Behringer powered mixer, but I have a Soundcraft UI16 with up to 6 AUX buses. As there are 5 of us, we can have a mix each and one for luck.

[Stub Mandrel]

Go a gig at my boomiest venue on Sunday. Stone flag floor, awkward layout, two bare walls facing each other exactly one 110Hz wavelength apart...

[Bill Fitzmaurice]

That's the room modes that I mentioned. Parametric is about the only cure for those, and not without cost. They manifest as a product of the positions of the room boundaries, the cab placement and the listener position. Move any one of those three and the result changes, so using a parametric to kill boom where you're standing can kill useful frequencies in the audience. That's why I always adjust my tone from well out front, and whatever that happens to give me on stage I just live with.

[gjones]

I am playing at a venue, which has a terrible boomy stage, next month.

 

Weirdly, the boom could only be heard onstage. But was so bad it was drowning the guitar out.

 

Last time I played there the solution was to turn all bass frequencies to zero on my amp and for the sound guy to then DI my bass through the PA, where he added the bass frequencies back again.

 

Hopefully I can do the same again.

 

 

Edited October 15, 2022 by gjones

[chris_b]

 

7 hours ago, gjones said:

I am playing at a venue, which has a terrible boomy stage, next month.

 

Weirdly, the boom could only be heard onstage. But was so bad it was drowning the guitar out.

 

I play on several stages where the boom can only be heard by me, not even the rest of the band! I try and pack the corner with cases and bags. Helps a little but only a little. I'm happy to do the gig if I know I'm the only one who can hear it.

[Bill Fitzmaurice]

7 hours ago, gjones said:

I am playing at a venue, which has a terrible boomy stage, next month.

Weirdly, the boom could only be heard onstage. But was so bad it was drowning the guitar out.

That's room modes too, although in the opposite of the usual fashion. The more common result is cancellation of low frequencies on and near the stage when reflections off nearby walls and ceiling meet the original wave front 180 degrees out of phase. When you move away from the stage into the room the relative boundary positions shift, the cancellations cease and the lows return. This phenomenon is what gave rise to the myth of wave propagation, the notion that a wave won't be heard until one is far enough away for the wave to develop. Believers of this myth have no explanation as to how headphones work. 🙄

 

Whether the bass is too much on stage and not enough out front or the other way around the best solution is to adjust the bass amp for the stage tone and volume and the PA for out front. The problem lies when you don't have PA. I don't know about the UK but in the States it's always been the band's responsibility to provide the PA in most venues. We used to say that we played the gig for free, what we were paid for was providing the sound system.