Topic: Ceiling Mount Considerations?

[HealthCov Chris]

I am permanently mounting a matched pair of mics to the rafters in one of my local venues.  There is already a pair centered (DIN) about 35' off stage, but due to the low ceilings they get too much chatter.

The venue has low ceilings (approx. 15'), is basic rectangle with capacity of approx. 500, and the rafter to hang the mics is approx. 6' from the speaker.  Recording from the back is not a quality option.  I frequently have onstage pair with sbd, but many bands don't allow sbd, so I want to keep a pair in the rafters directly in front of the speakers to get the cleanest recordings with minimal chatter.  Does anyone have experience and/or specific suggestions regarding the location/position, etc. of the mics before I hang them?  Here is a couple pics of the venue/stage area to hang the mics.  I assume the best area is between the mirror ball and the first light module.

[Gutbucket]

A wide pair with each microphone hanging directly in front of each PA speaker, up at the same height as the PA speakers are above the floor.

Small omnis work great for this for a few reasons: They will be easiest to hang and manage over time as they needn't point directly toward the speakers, they are most likely to sound natural with a flat extended and open response, and from that close but high position they should get a very good balance of clear PA sound dominating over the enthusiastically engaged up-front audience, even with way too much disengaged audience chatter happening pretty much everywhere else.  This will sound very much like a direct SBD feed with a touch of ambiance in it.

The question that remains is which cross-beam to hang them from. The closest one with lights and mirror ball looks to be a bit too close.  The second one back could be perfect but might be a bit far if the room is super chatty even up front.  Ideal is likely halfway between the two, but that's not likely to be practical.  Try both positions if you have the access to do it, which is the only way to really know for sure.

If omnis at the first beam are too close, yet turn out to be too far away at the second beam, subcards (maybe even cardioids) from the second beam could be just right, but then you'd need to keep them oriented correctly, both vertically and horizontally, which is a lot more hassle than simply hanging a pair of omnis from their own cables.  Give the omnis a go first.

[voltronic]

I don't have specific experience doing this, but I have a couple thoughts that may or may not be helpful:

1. Be careful of proximity to the projector, which I imagine gets used during shows. Ones used in large venues often have loud cooling fans. I found that if the hard way once when recording from a balcony.

2. How low can you mount your mics without interfering with said projector, if you're mounting them between there and the stage? Because I'm thinking of avoiding strong early reflections from the ceiling, and you probably don't want your mics behind the projector because of the potential noise. You want that noise source in the mics' rear nulls if possible. Some may recommend using hypers to avoid the ceiling reflections, but the rear null will not be as deep as cardioids so there's a trade-off.

3. Mounting an array this close to the stage means you'll need to aim your mics quite wide to capture the PA properly. Two ideas come to mind for that: a "hybrid" NOS of 30 cm but with a 110° angle, or an array I've had a lot of success with recently (for acoustic recording, mind you) - the Gerzon at 120° with only a 5 cm capsule spacing. This one allows you to easily add more spaciousness in post if you choose.

4. I just saw Gutbucket's reply about omnis. I would not have thought to recommend them because of the aforementioned audience chatter, but they could actually work great here for reasons he details. It would certainly be easier to set up than the near coincident setups I've described.

[Gutbucket]

Yeah, wide omnis in front of each speaker for several of reasons:

It gets the mics closer to the PA speakers.  Each will be directly on-axis and have good close proximity to each speaker.  That makes it like a stack tape, or rather a stereo stack tape of both stacks, and a perfect substitute for a soundboard patch when one is not available.  Depending on the PA speakers, better than a stack tape.  Most of the time I'd take it over a soundboard patch any day.

Excellent balance between direct-PA-and-on-stage-sound versus reverberent-room-and-audience-sound.  Physical location of the microphones on axis and significantly closer to the PA speakers on either side than all other sources of sound are part of this.  But also, as long as each mic is the same distance from the speaker on its side, in addition to being clear and dryish, what is picked up from the PA will retain high phase correlation - much like what one gets from a board feed or on-stage coincident pair, while pickup of room and audience sound will be highly de-corellated.  That means reverberance of the room and any specific audience voices will have significant phase, timing and level  differences between channels.  That makes the room sound better, bigger, more open, even if it doesn't when there in person, and will tend to make the perception of any individual annoying audience members which can still be heard over the music more diffuse, and a lot less direct, clearly understood and in your face.  Projector noise will also be be farther away, and likely to only be significant for quiet performances with a quiet audiences.

Easy to rig.. except for the ladder climbing that needs to be done regardless. Just hang them. no pointing needed, no worries of twisting or changing orientation over time.

Proven to sound great in other similar places.

Will mix well with whatever other mics you may want to use, but you probably don't need those unless you want to include them.  If so this pair should make for an excellent foundation of the mix.

[Chanher]

EDIT: gutbucket posted more while I was writing this, but yes, what he said.

A wide pair with each microphone hanging directly in front of each PA speaker, up at the same height as the PA speakers are above the floor.

Small omnis work great for this for a few reasons

This is something I've always wanted to try, and it's based on numerous recordings I recall that sounded sooo good to me. The closeness to the PA speakers provided an upfront "soundboard" feel and clarity but using the (very widely) spaced omni's simultaneously provided huge soundstage and a wonderful ambience/room feel. It might feel counterintuitive to use omni's since one of your goals is to eliminate chattiness but I think you will be surprised at the results.

I've curiously followed people using spread cardioid's and I will admit I found the results to be better than I expected; I'm sure it's violating numerous stereo recording principles but I personally wouldn't hesitate to at least try cardioid mics mounted directly in front of each PA speaker. Ideally you would mount mics that have interchangeable capsules and you could try both omni's and cards. If anyone wants to provide the reasons spread cardioids are a bad idea I'm certainly open to hearing them.

I don't think you could go wrong with mounting a near-coincident pair in the center BUT as Voltronic states, you could be interfering with the projector and/or picking up the cooling fan of said projector. If you find a way to avoid the projector and it's potential problems, I like Voltronic's suggestion of some kind of NOS. Nice and wide to get the PA speakers but it would still pick up a little of the stage amps/drums which IME is usually (but not always) a good thing. If we're getting greedy then you could do a 3-mic mount with an extra wide set of directional mics aimed at the PA speakers with a center directional mic aimed at the stage and picking up drums and amps directly from the musicians themselves.

If I ever get a chance to permanently mount in a venue, I'm definitely gonna try omni's directly in front of each PA speaker.

[HealthCov Chris]

Ok, so what if I can't get my mics as low as the pa?  The pa is angled slightly downward and inward.  Owner doesn't want anything hanging down that low.  I guess I just angle the mics (if cards) down towards the center of the pa?  Same with omni mics?

[admkrk]

Ok, so what if I can't get my mics as low as the pa? 

Go a little farther back. As long as they are above where anyone can reach, there should not be a problem. Using tiny mics helps also, since they will not even be noticed once the lights are down, and maybe not otherwise.

[Chanher]

Ok, so what if I can't get my mics as low as the pa?  The pa is angled slightly downward and inward.  Owner doesn't want anything hanging down that low.  I guess I just angle the mics (if cards) down towards the center of the pa?  Same with omni mics?

Omni’s can be hanging straight down if you want, I would get them as low as the owner will allow. Some Dpa 4060’s seem like a great low-pro option, Dpa aficionados plz chime in which version is best suited for this as I am personally interested in doing this one day.

If you end up trying cardioids then my instinct would be to keep them pointed straight forward, as you still want to keep the off-axis rejection minimizing crowd noise. Maybe poined SLIGHTLY downward if they ask you to keep them pretty high up and out of the way.

Sounds like you’re planning on using the rafter that is 6’ from the speakers to mount the mics; from my limited stack recording experience that seems like a good distance. Stack recording experts chime in.

[Gutbucket]

Ok, so what if I can't get my mics as low as the pa? 

Determine the radiation angle limits of good coverage from the PA speaker.  If you can see the high frequency horn through the grill of the speaker, the good coverage angle is typically the same angle as the angle of the horn walls.  Confirm by listening even if you can't see the high frequency horn by standing on the floor and listening to the PA as house music plays.  Move forward and back near the PA speaker while listening for the point at which the high frequency clarity and level suddenly drops off when moving forward, toward the stage.  Once you determine where that point is, look up at the speaker to get an idea of how far off axis that is from where the speaker is pointing - you'll now have a good idea of the downward angle that defines the edge of good coverage. The upward angle from the speaker where the same high frequency drop off thing happens should be more or less a mirror image of that.  You'll want the microphone somewhere between those two extremes. With the speaker angled down somewhat the upper angle will be different than the lower one with respect to the room, but should be symmetrical with respect to the speaker.  Safer to be a bit inside that good coverage angle rather than right at the edge of it.

From the photos it looks like a mic suspended from the first beam, between the mirror ball and robot light, hanging down so that it's the same height as the bottom of of both of them, is likely to be well placed withing the good coverage angle.  Mic on the other side arranged symmetrically with respect to this one.

Go a little farther back. As long as they are above where anyone can reach, there should not be a problem. Using tiny mics helps also, since they will not even be noticed once the lights are down, and maybe not otherwise.

All that.  I'd think bottom edge of the mirror ball would be okay, but depends on the owner.  If you have to go higher it may help to move back to the second beam to stay within the good coverage angle, but it really depends on what the good coverage angle is and how far down the speakers are pointed.

[Gutbucket]

I've curiously followed people using spread cardioid's and I will admit I found the results to be better than I expected; I'm sure it's violating numerous stereo recording principles but I personally wouldn't hesitate to at least try cardioid mics mounted directly in front of each PA speaker. Ideally you would mount mics that have interchangeable capsules and you could try both omni's and cards. If anyone wants to provide the reasons spread cardioids are a bad idea I'm certainly open to hearing them.

No reason spread cardioids can't work.  Stereo Zoom doesn't apply in this case of pseudo-close mic'ing the PA, but where it does the trade off relationship between angle and spacing translates to a wide-spaced pair of cardioids having very little if any angle between them, more or less like a pair of omnis.  They then behave like a pair of omnis in terms of stereo recording angle and imaging, only with a forward sensitivity bias.  They won't sound quite the same due to that forward bias, mostly the room and audience contribution will be different and not as natural as a pair of omnis.  But when that forward bias is needed it might be a better choice.  That might make sense from the second beam back.  If so, point them forward directly toward the speakers.

[goodcooker]

I took a long look at a similar situation before the owners finally decided not to allow it.

If it was me I'd put two Line Audio CM3/4 mics split AB in line with the inside of the hanging speakers on the Ibeam back from the lights and mirror ball. That looks to be 12-15 feet from the stage lip. If you use some inexpensive crab clamp/ball heads like the Camvate ones https://www.bhphotovideo.com/c/product/1369252-REG/camvate_c1465_crab_clamp_5_8_27_ball.html you can switch up later if you don't like your spot and could move them up closer if you aren't getting a good balance.

If you go with omnis get them as close as possible like hanging from that closest spot right in front of the speaker.

Directional mics should work just a little farther back but you are going to get some chatter from underneath no matter what you choose with those low ceilings. If you have access to the house sound person ask them what the coverage of the speakers is. I was surprised to learn that I was running my mics too high at a local spot in an effort to get away from chompers and was above the focus of the hanging line arrays. Just by looking at them I thought the focus would have been higher up in the air but talking to the FOH guy who hung them proved me wrong.

Subcards will be more forgiving about placement and will still give rejection from the rear and sides somewhat.

Good luck with this. I wish my local spot had allowed me to do this. It would have made life a lot easier at a place where I record at least a few times per month.

[Gutbucket]

The mics too high thing can happen with any PA, but is most likely to happen with line-array PAs, which typically consist of an array of separate, close-stacked mid & high frequency modules.  Those are most often "flown arrays" hanging from the ceiling, but not always, and tend to be J-shaped with the top-modules pointing straight out into the room and the bottom-most modules pointing more downward providing coverage close to the stage.  Each of those mid & high frequency modules is designed to have a rather wide horizontal coverage pattern, but a very narrow vertical coverage pattern.  The narrow vertical coverage angle helps the stacked modules hand-off to each other seamlessly without too much overlap.  The desired vertical coverage is then mostly achieved by the J-shaped curvature of the array.  That also means that at top of the array, the vertical coverage pattern cuts off very abruptly not far above horizontal, which is also intentional. The array projects sound more evenly where it is needed, sending significantly less energy toward the ceiling, or up into the sky if outdoors.

This means the sound up above the top of the array will tend to have lower SPL and be significantly less-clear sounding, so putting mics up at that level or higher can be a problem, even though its nice to get them up as high as possible to get them farther away from the audience noise below.

I like to fly my mics high when I can to reduce nearby audience chatter, and when I do I'm always careful to take a good look at the PA to try and figure out what might be too high.  Usually to be safe I go no higher than the top of the PA, and in doing that I've fortunately not had a problem with this for a long time.  Last time I did was over a decade ago at an outdoor amphitheater that was using old-school  point-source boxes stacked on either side of the stage, not a line-array PA.  I just put the mics up too high and it was very dull sounding up there, much like being too close when there isn't any fill speakers up front.  Those point-source PA behave more like a smaller PA speaker, and after that I learned to look at the high frequency horns and keep the mics inside the angle defined by the horn walls.  The mics need a direct "line of sight" into the horn's throat.

[Chanher]

Thanks to everyone who posted, lots of good info here. Please keep us updated on your progress with audio samples if you're able to!

[grawk]

if you’re friendly with the manager, have something playing loud through the pa when you’re flying the mics and tune the placement by ear

[HealthCov Chris]

Here’s my first attempt.  Not bad for a $200 matched pair. 
https://archive.org/details/rb2024-01-10.InsideOut_s7