Creating dead zone for hearing protection

[dnathan]

It sounds like centering the subs between the high end cabs would be the best option - and perhaps extend the stage. I could make a sub and have the exhaust exit the sides instead of the back??

But yes, Nicolai, the drummer is taking all the hits. IEMs, pads, no sub nearby... I'm thinking a hybrid kit would work. An electric snare and cymbals with acoustic toms. I don't know if an acoustic kick can be tamed a bit, or if I would even need that. It's really the lead guitar, cymbals and HF crowd cheers that hurt the most.

 

[gafftaper]

The advice in this thread has been rock solid. I don't know any pro audio people who would recommend Bose. Buy gear from someone like: QSC, Electro Voice, or JBL and take the money saved to go buy some high quality custom molded IEM's you'll be just fine.

 

[TimMc]

It sounds like centering the subs between the high end cabs would be the best option - and perhaps extend the stage. I could make a sub and have the exhaust exit the sides instead of the back??

But yes, Nicolai, the drummer is taking all the hits. IEMs, pads, no sub nearby... I'm thinking a hybrid kit would work. An electric snare and cymbals with acoustic toms. I don't know if an acoustic kick can be tamed a bit, or if I would even need that. It's really the lead guitar, cymbals and HF crowd cheers that hurt the most.

Go back and re-read my comment. Center clustering the subs will put 50% of their energy right onto the stage.

 

[dnathan]

Thanks Tim. I re-read it. It sounds like something like this would work best:

But the red indicated seems like only a partial reality. Wouldn't the stage be red too? Do I have it right that the exhaust is what comes out of the port, and isn't that usually in the back of the sub?

 

[TimMc]

Without getting into what's wrong with this design from a top-box perspective...

No, the port (it's not an "exhaust", it's part of an acoustic filter) is where the bottom octave comes from in a bass reflex cabinet (and not all subs are bass reflex) and typically the port is on the front where the loudspeaker is but it isn't absolutely necessary for it to be there. Moving it to sides or back creates other issues beyond this discussion, however.

Subwoofers tend to be nearly omnidirectional in their radiation as the wavelengths are sooooo looooonggggggggg. Omni as in 360 degrees (spherical) or when on the ground, hemispherical with the ground providing a boundary effect that effectively boosts perceived output by a couple dB - in all directions.

Making directional sub arrays involved multiple subs, delay on some of those subs (requires granularity of DSP), and usually 1 amp channel per sub (more granularity). Not cheap but it works, working best at the center frequency of cancellation and gradually becoming less directional as you get further than 1/2 octave from the center freq.

In the model you show there is unlikely to be a ground-based sub array what will be accepted by the Aesthetics Committee (or worship committee or altar society, etc) as they tend to be physically large and can't be hidden under the stage and remain effective. There must be free air clearance around the subs that are at least 1/4 wavelength from any obstructions or architectural or furnishing reflections. If you do a "reversed & delayed cardioid" deployment you can't have the subs up against a wall, the front of the stage, etc. There must be clearance all the way around the array. End fire arrays take up more room on the sides of the stage and, like the cardioid, can't be against anything or withing 1/4 wavelength of reflective objects/walls etc.

 

[dnathan]

>In the model you show there is unlikely to be a ground-based sub array what will be accepted by the Aesthetics Committee (or worship committee or altar society, etc) as they tend to be physically large and can't be hidden under the stage and remain effective.

You're all so kind and wise.
So it shouldn't be under the stage. That makes sense. It's not for a church, so I can put them in front without aesthetic issues - just not next to each other. Are you saying that getting them off the ground would help? I could put them on the stage, hang them from a truss or even under the drummer riser (but that would diminish free-air clearance, so no). I like the idea of the guitarist being able to walk out onto it, increasing the stage real estate.

If I picked up a couple QSC K12.2s, as Mike suggested with a QSC KS212C for a sub, where would you put it on the image above? Would I need two, or would one suffice with a pair of K12.2s?

 

[TimMc]

Keeping subs on the ground gives more SPL regardless of other deployment techniques.

Grouping subs together in one location reduces or mostly eliminates power alley (comb filter) but creates other considerations - if centered in front of the stage, the stage will also be uniformly washed with Subbagge®; if set to one side, alignment with the top boxes further away can be an issue.

Setting subs left and right will create a comb filter based on the distance between the subs, or power alley. Where between the subs the lobes and nulls occur will vary with frequency (it's that distance/speed of sound thing) and accordingly the audition will change based on an audience members physical proximity between the subs. For more info (with visuals!) I suggest https://www.prosoundweb.com/topics/sound_reinforcement/in_search_of_the_power_alley/

Note that in the setup in your illustration, left/right subs will put the same power alley on stage as will be in the house. One of the reasons we use the "reversed, delayed sub cardioid array" deployment is to reduce the the power alley on stage. The SPL reduction isn't as dramatic as directly behind the sub array but it helps with performers who are sensitive to either the inconsistency of power alley/null valley across the stage or who don't like that much deck rumble.

Another In General thing - getting speakers up in the air is a Very Good Thing for several reasons. If you can do that I suggest you also fly the subs (or 2/3 of them, and put the others on the ground to keep a bit more Subbagge® near the audience), centered and at least 16' above the stage. Flying subs gives the most even coverage to the majority of the room and you get the benefit of a cluster without having it in front of the stage. By not being tied to ground supported top boxes you can deploy a flown "exploded cluster" of top boxes or look at other speakers with different nominal coverage angles... and remember that the nominal HxV pattern is only valid at a rather narrow range of frequency (often above 2kHz and narrowing by 5kHz or so). To the extent possible you want only 1 to box covering a given spot in the room; if you want "stereo" then each "side" has to cover 100% of the room or the folks not in the middle lose out.

So all of the above boils down to this: It Depends. -Ivan Beaver, Danley Sound Labs

 

[dnathan]

Wow, interesting. It sounds like hanging it from a truss would be the most important consideration. We would have a truss behind the drummer. That would give him his groove as well. It would be our only sub for most gigs.

If I put a plexiglass drum shield on the drummer's right side and the sub hanging to his left, I could (mostly) stand there and reduce the dB of both the kit and the sub! People might think a single shield is strange, but that's fine. I could move around, but mostly hang out there. The sub wouldn't be exactly centered, but pry close enough. Thoughts?

 

[dnathan]

Here is a stage plot of what I'm thinking. The orange box is the sub on a stand. The black line is a plexiglass sheet. The light blue boxes are the QSCs. The dark blue are trusses. The green lines are perimeters of the stage and the green box is a mini riser so that I can sing from the back of the stage as still be visible. This is a tiny stage for wedding purposes where there is no room for anything. The question is how much the black plexiglass would help with LF.

 

[MNicolai]

A plexiglas sheet will not block low frequencies. The gymnastics you’re going through to justify these strange stage/PA layouts and systems leads me to believe you’re not appropriately as concerned about making good music or putting on a good show as you are about making yourself comfortable on stage.

Nobody wants to see a show with the lead singer in the back. It’s like going on a first date and getting to the restaurant only to discover your date can’t hold up their end of a conversation so you have to bail after the appetizer or subject yourself to another 90 minutes of awkward "Why am I still here?". The lead singer is the conduit through which the band communicates to the audience, and burying yourself in the back row will directly impede that, regardless of a small riser you may be standing on.

It’s time to stop designing a gig in a vacuum and start making platinum records.

 

[cdiamondz]

I'm starting a rock band and I have tinnitus. As singer/founder I can design it to protect my hearing. I'm planning in-ear monitors, electric drums, and a PA speaker(s) (probably Bose L1) in the front corner of the stage. I need advice on ways to create a dead zone for myself that especially cancels out the high lead guitar frequencies. I'm assuming the Bose would be the best because of its clean sound, but I'm open. I'm also concerned about crowd noise. Thoughts?

If IEMs weren't a requirement, I'd recommend Earasers. I used them in marching band and even their basic model cut a lot of the volume and kept the sound even. (Not sponsored by the company, just a user of their product.)