Great Job Michael, thanks for sharing. Being a bass singer and an audio engineer it’s always awesome when the subs are just right. Subs are always the foundation. Great job on this foundation.
That is an amazing implementation, you took the opportunity to set up those “weird” configurations. I like the idea of subs on the ceiling, it looks very clean.
I’m not one to comment, but your videos are amazing. I have a huge passion for Live Audio, and I am so lucky to come across your channel to learn more and more! Thank you for your hard work!!
Hey Michael, I discovered your channel a few days ago. I just subscribed! This video was probably the 3rd video I watched. But I work as a Tech Director at local church. We have a PA system that’s 10 years old and is on its last leg. I started a design in Ease Focus 3 deploying a QSC LA112 rig. I would love to hire you look over my design. This not rush project, realistically we would probably do the upgrade in July or August.
This was another gem, Mr. Curtis! Probably way beyond anything that I'll ever be involved in, but a total geek-out for a live audio fanboy. On related note, perchance do you have any content in which you discuss your background? I watch these vids and I find myself wondering, "how DOES he know so much at the ripe age of... I'm guessing 23??" (I jest of course, but seriously, you do look young!)
Great video! Loving all your content! I see all your hard work you drive into your clients. Might have to hire you here soon also! I would love to have a system designed by you! Keep up the great work!
Hey Michael, first of all, thanks for another great video! It is one that raises a question I've had in my mind for quite some time regarding flown vs. ground positioned subs. There seems to be an opinion amongst many audio engineers (as well as system engineers for that matter) that flown subs should in best practice always be accompanied by at least some ground placed subs as a sort of fill, or else there will be a loss in impact and/or focus of the low end. It is a statement that I personally can't really see the logic in and on the few occasions that I have been mixing on a rig with nothing but flown subs I haven't really found an issue with it either, but rather enjoyed it since the low end I perceive at FoH is a closer representation of that perceived close to stage, in comparison to that of a classic approach with subs positioned only on the ground. In terms of SPL the low end will obviously have a lesser impact in front in relation to further back in the audience with nothing but flown subs (not in comparison to itself, but in comparison to ground placed subs), but this is the whole point of flying the subs in the first place - a more even coverage. As long as there's enough power in the subs to, by increasing their output, have them compensate for that loss in the front this should theoretically not be an issue. The only argument I myself can come to think of that supports this opinion is that one gets more direct sound from the ground placed subs before any room reflection blends in with it in comparison to the flown subs. This, however, would again only benefit a selected few first rows in the audience and not contribute to a more coherent over all soundscape in the room. Maybe I answered my own question here but if you have additional thoughts or opinions on the subject I would be glad to hear them. Cheers
Hey, Jack. Great question and yes I do think you ended up answering much of it. Just like we might design a down fill or front fill system for the first few rows if our line array is optimized for the 3rd row and back, having a small sub array down front can be helpful and restore some of the "front row" experience. If the geometry of the rig works out so that both the mains and flown subs have great coverage in the first row, then no need to add the additional subs. Sometimes you see at larger concerts a HUGE main sub hang, but then a wide sub arc of additional subs on the ground. That's usually an infra sub rig on the ground (15-30Hz), then the main sub hangs handling 30-80Hz (or wherever the ideal crossover is for that system).
1. Keeping all the subs together is the most efficient use of energy. 2. The wide audience called for a wide pattern, which can be done in a center sub setup. 3. Flying the subs kept the stage clean AND made the sub energy more even from front to back. 4. The cardioid pattern kept LF energy from bouncing off the back wall behind the stage.
Unfortunately cardioid arrays start to fall apart and not work effectively when many hard boundaries around them, so I would advise against placing them under the stage.
Great stuff Michael! I'm in a similar situation with subs on each side of our stage which runs the width of the room (about 100ft). We're currently running the entire system in mono and I'm getting some major power valleys near the front center of the room (just by ear). I'm working on rewiring to run stereo and thinking about running different low end sources to each side (kick-in to the left and kick-out to the right, etc.) to try and minimize these valleys without getting new gear. Thoughts on this? I think Dave Rat said he does this for some shows he's done, figured I'd give it a try.
I'm not totally sold on Dave Rat's method because even though the two mics (kick in and out) have slightly different timings and frequency response they will still largely be correlated at the fundamental. So, even if they're panned out, there's still so much that's similar between the two that you may get "some" difference, but I think you'll end up back at square one. I haven't tried Dave Rat's technique live, but if I compare the IR of two different mics and sum them I still get a ton of cancellation.
Kick in and kick out are both to me the essential parts of the kick sound. If they are hard panned, people who are not directly in the middle will not get the full kick sound, it doesn't sound like a good idea to me at all.
@@Zamsky39Yeah, I gotcha. Right now we have major comb filtering, so I’m thinking maybe it’s a slight improvement to try and minimize that if we can’t fully replace the wide left right setup anytime soon.
Great stuff Michael! Quick question on the dual 18s facing each other. What is the math behind the spacing between the two facing each other being 6 inches apart?
At 10:30 I started to think in terms of flipping the room over so the ceiling is the floor, the subs are on the ground and the audience is on the ceiling. Usually we don't think about the fact that a ton of low frequency energy bounces off the floor and goes straight up. Did any additional calculation go into taking advantage of the ceiling reflections to focus more downwards? I can see the ceiling is pretty close, looks like 12" max from the top of the cabinet, let's say the cabinets are 26" tall, that gives a 25" distance from the center of the drivers to the ceiling. Correct me if I'm wrong but that means the reflection straight down would be delayed 1/4 wavelength at 67hz, but that difference would increase as the angle changes as you walk towards the back. I'm not sure if any of this was part of your strategy but this is where my brain went. Did any additional thought go into projecting downwards or accounting for the ceiling height?
Great point! To be honest I didn't worry about the ceiling reflection too much since the room was so large and reflective to begin with. So many other wall reflections come into the equation as well that that single reflection point isn't as problematic as it might seem,
I would be scared to sit in there with those massive subs placed over my head! Weren’t you getting rattling noises? From the pictures, to me it looks like the subs will make everything shake and rattle around them.
LOVE learning so much about sub arrangement from your videos. I run small local shows, and I run the KS212C's, which are incredible for easy cardioid setup and mitigating stage noise. I'm curious if it would be worthwhile in smaller rooms that are longer than they are wide, if it would be beneficial to split those subs that 5.5 feet to narrow the overall pattern to minimize wall bounce? Is it worth it? Also, if I were to split them, would they need to be centered? Or can I just aim them towards center? Thanks for everything you do on here!
Hey, Ben. Great questions here! With a pair of KS212C's in a long, narrow room I would do exactly what you mentioned: put them 5 1/2 feet apart in the center in front of your stage. The caveat here is that an active cardioid setup needs space from boundaries besides the floor to work properly. So this would only work if your stage does not have a hard front. If you've got an open stage front I'd still put your subs at least 3ft downstage of your stage to help get even more cancellation at the rear.
@@MichaelCurtisAudio Thanks a bunch! If I am stuck to a hard stage front, I feel like the next best thing is stacking them together on stage to one side? If I had the horizontal space I could still do the split setup, but I'm curious if it would just make an odd pattern if they're off center?
Thanks, Chris! EASE Focus 3 is what I used for putting the whole design together, which supports many different manufacturer's products. I used MAPP 3D from Meyer Sound to show the illustrations.
I’ve always been told, and certainly felt like, subs on the floor, coupled to that surface, made the low end more…felt, for lack of a better word. Based on this design, do you believe there is any loss in “thump”, especially that 60hz-ish kick?
No loss at all! The church I worked with on this sub setup made it very clear that they alllll about the low end. It had to hit hard, especially in the 40-80Hz octave. And this system definitely delivered! If anything flying subs makes sure that more of the audience is able to "feel" the subs, not just the front row.
@@MichaelCurtisAudio very interesting. Can’t believe I’ve just now found your channel. I lead the production team at a church in Bentonville so I’ll likely be giving you a holler!
The ceiling deck is also a boundary. In new construction I have requested a concrete pad on the roof deck to improve the response of ceiling mounted subs.
Rigging was approved by the integrator. I set up my engagements where I give them where I'd LIKE to have speakers, then they run the necessary calculations to approve that. You're right that those subs aren't rated to be flown with any conventional hardware from JBL, but it doesn't mean that they can't be secured in the air by other means. The unistrut cage and lag bolts solution used was a very sturdy solution. I've never heard that subs facing each other would damage drivers. I've seen several setups from seasoned experts at Meyer Sound with similar setups. Do you have a specific resource or article you can point me to that says otherwise? I'm very curious.
@@MichaelCurtisAudio I'm trying to find the article in question in regards to the driver damage statement. I could likely be mistaken. Since that's the case, I'm going to remove that part of my comment as to not spread misinformation.
It depends on the situation. In this video the VRX hangs in the tunnel are relays - they're covering a completely separate zone which the main PA "hands off" coverage to.
Newbie here trying to understand sub arrays. Watched a few of your videos including the ones on the inline gradient array and the inverted gradient array. The delay stack looks like an inline gradient array, but what is configuration of the main stack with the boxes facing each other?
Great question, Terry. The main stack is the same thing as inline gradient, but the boxes are facing each other so that their acoustic centers are close together. This makes the pattern wide. If the boxes are farther apart the coverage pattern starts to narrow, which is what I don't want with a wide audience to cover.
Thanks Michael. So is the way to think of the two boxes facing each other is they act as one box in an inline gradient array? So the front two boxes are the front and the rear two boxes are the rear box in the simplified two box inline array in your other video?
It's starting to make sense now. Thank you! On a slightly different topic, I recently saw on the Billie Eilish tour, the subs were hung in a vertical array directly behind the main array (L-R configuration). Big L-Accoustics setup. Could you perhaps do a video on this sort of setup? It didn't make a lot of sense to me, but obviously I'm missing something. PS Love your videos - learning so much.
If it's a wide room, i would stack them up vertically. The top facing forward, the middle facing backward, and the bottom facing forward. If it's narrow, I would place them in a horizontal line to narrow the coverage.
@@MichaelCurtisAudio unfortunately we don’t have the height to stack them the stage is not tall enough but it is a wide room. The space in front of the stage is 100’x60’. Flying up high could be an option as we have high ceilings but they don’t have the money at the moment to do that so we are stuck with them on the ground. We also don’t have to use all 3 if it’s not the best fit.
@@michaelyoung7911 Best scenario would be to fly them over the center of the stage once you get budget. If not, I would do a two-element inverted gradient stack. Just like the three-box array I mentioned, but the bottom one facing forward and top facing back. If that's too high, then I would just put them facing each other on the ground with a 4-6" space in between them.
@@MichaelCurtisAudio yeah our stage isn’t high enough to stack any :( so we will look into your last option. One of our pastors did ask if it would be easier to add a 4th box. I’m gonna have to download these prediction programs and start figuring this out! Thank you!
Great Job Michael, thanks for sharing. Being a bass singer and an audio engineer it’s always awesome when the subs are just right. Subs are always the foundation. Great job on this foundation.
Thank you very much! Keep the bottom : )
That is an amazing implementation, you took the opportunity to set up those “weird” configurations. I like the idea of subs on the ceiling, it looks very clean.
Thank you so much!
I’m not one to comment, but your videos are amazing. I have a huge passion for Live Audio, and I am so lucky to come across your channel to learn more and more! Thank you for your hard work!!
Well I appreciate you coming out from the woodworks and saying hey! Keep learning and developing your craft. Happy my channel has been helpful to you.
Hey Michael, I discovered your channel a few days ago. I just subscribed! This video was probably the 3rd video I watched. But I work as a Tech Director at local church. We have a PA system that’s 10 years old and is on its last leg. I started a design in Ease Focus 3 deploying a QSC LA112 rig. I would love to hire you look over my design. This not rush project, realistically we would probably do the upgrade in July or August.
This is incredible, thanks so much for sharing your experience!
Glad you dig it! Was a ton of fun to put together.
This was another gem, Mr. Curtis! Probably way beyond anything that I'll ever be involved in, but a total geek-out for a live audio fanboy. On related note, perchance do you have any content in which you discuss your background? I watch these vids and I find myself wondering, "how DOES he know so much at the ripe age of... I'm guessing 23??" (I jest of course, but seriously, you do look young!)
Thank you for the kind words! That would be a fun video to put together : ) Not quite 23, but 31!
Your work are amazing…thank you for sharing your knowledge.
Thank you very much!
Great video! Loving all your content! I see all your hard work you drive into your clients. Might have to hire you here soon also! I would love to have a system designed by you! Keep up the great work!
Thank you so very much, Dave! Yes, I'd love to work on a project together.
Hey Michael, first of all, thanks for another great video!
It is one that raises a question I've had in my mind for quite some time regarding flown vs. ground positioned subs.
There seems to be an opinion amongst many audio engineers (as well as system engineers for that matter) that flown subs should in best practice always be accompanied by at least some ground placed subs as a sort of fill, or else there will be a loss in impact and/or focus of the low end. It is a statement that I personally can't really see the logic in and on the few occasions that I have been mixing on a rig with nothing but flown subs I haven't really found an issue with it either, but rather enjoyed it since the low end I perceive at FoH is a closer representation of that perceived close to stage, in comparison to that of a classic approach with subs positioned only on the ground.
In terms of SPL the low end will obviously have a lesser impact in front in relation to further back in the audience with nothing but flown subs (not in comparison to itself, but in comparison to ground placed subs), but this is the whole point of flying the subs in the first place - a more even coverage. As long as there's enough power in the subs to, by increasing their output, have them compensate for that loss in the front this should theoretically not be an issue.
The only argument I myself can come to think of that supports this opinion is that one gets more direct sound from the ground placed subs before any room reflection blends in with it in comparison to the flown subs. This, however, would again only benefit a selected few first rows in the audience and not contribute to a more coherent over all soundscape in the room.
Maybe I answered my own question here but if you have additional thoughts or opinions on the subject I would be glad to hear them.
Cheers
Hey, Jack. Great question and yes I do think you ended up answering much of it. Just like we might design a down fill or front fill system for the first few rows if our line array is optimized for the 3rd row and back, having a small sub array down front can be helpful and restore some of the "front row" experience.
If the geometry of the rig works out so that both the mains and flown subs have great coverage in the first row, then no need to add the additional subs.
Sometimes you see at larger concerts a HUGE main sub hang, but then a wide sub arc of additional subs on the ground. That's usually an infra sub rig on the ground (15-30Hz), then the main sub hangs handling 30-80Hz (or wherever the ideal crossover is for that system).
Wow, very impressive! Awesome job!
Thank you so much!
I would like to hear your live performance sounds. Not only theory 😢
So your reason for doing the subs like that was to keep the low end in one palace for a deeper low end and it doesn’t travel all over that room.
1. Keeping all the subs together is the most efficient use of energy.
2. The wide audience called for a wide pattern, which can be done in a center sub setup.
3. Flying the subs kept the stage clean AND made the sub energy more even from front to back.
4. The cardioid pattern kept LF energy from bouncing off the back wall behind the stage.
Here to confirm Michael Curtis identifies as a Pioneer 👏🏾
Ha! Just trying to remix some knowledge from the 50's into new contexts : )
Is it possible and Curtis approved to use this front sub-array design and instead of flying them put the subs under the stage?
Unfortunately cardioid arrays start to fall apart and not work effectively when many hard boundaries around them, so I would advise against placing them under the stage.
Great video, as usual
Much gratitude : ). Glad it was helpful.
Great stuff Michael! I'm in a similar situation with subs on each side of our stage which runs the width of the room (about 100ft). We're currently running the entire system in mono and I'm getting some major power valleys near the front center of the room (just by ear). I'm working on rewiring to run stereo and thinking about running different low end sources to each side (kick-in to the left and kick-out to the right, etc.) to try and minimize these valleys without getting new gear. Thoughts on this?
I think Dave Rat said he does this for some shows he's done, figured I'd give it a try.
I'm not totally sold on Dave Rat's method because even though the two mics (kick in and out) have slightly different timings and frequency response they will still largely be correlated at the fundamental. So, even if they're panned out, there's still so much that's similar between the two that you may get "some" difference, but I think you'll end up back at square one.
I haven't tried Dave Rat's technique live, but if I compare the IR of two different mics and sum them I still get a ton of cancellation.
@@MichaelCurtisAudio That makes sense. Thanks for the helpful response!
Kick in and kick out are both to me the essential parts of the kick sound. If they are hard panned, people who are not directly in the middle will not get the full kick sound, it doesn't sound like a good idea to me at all.
@@Zamsky39Yeah, I gotcha. Right now we have major comb filtering, so I’m thinking maybe it’s a slight improvement to try and minimize that if we can’t fully replace the wide left right setup anytime soon.
@@Zamsky39 Agreed. Dave Rat knows his stuff and is a fantastic FOH engineer, but I don't jive with him on that specific workflow he uses.
Great stuff Michael! Quick question on the dual 18s facing each other. What is the math behind the spacing between the two facing each other being 6 inches apart?
Thank you! It's so that the sound emanating from the front of the woofer has space to move around the cabinets and out into the audience.
At 10:30 I started to think in terms of flipping the room over so the ceiling is the floor, the subs are on the ground and the audience is on the ceiling. Usually we don't think about the fact that a ton of low frequency energy bounces off the floor and goes straight up. Did any additional calculation go into taking advantage of the ceiling reflections to focus more downwards? I can see the ceiling is pretty close, looks like 12" max from the top of the cabinet, let's say the cabinets are 26" tall, that gives a 25" distance from the center of the drivers to the ceiling. Correct me if I'm wrong but that means the reflection straight down would be delayed 1/4 wavelength at 67hz, but that difference would increase as the angle changes as you walk towards the back. I'm not sure if any of this was part of your strategy but this is where my brain went. Did any additional thought go into projecting downwards or accounting for the ceiling height?
Great point! To be honest I didn't worry about the ceiling reflection too much since the room was so large and reflective to begin with. So many other wall reflections come into the equation as well that that single reflection point isn't as problematic as it might seem,
This church is in Carrollton, TX right? Which church is it? I'd love to go visit and take a listen to the system since I'm in that area.
Yup! It's Bethania USA - www.bethaniausa.com/english-home-page
I would be scared to sit in there with those massive subs placed over my head! Weren’t you getting rattling noises? From the pictures, to me it looks like the subs will make everything shake and rattle around them.
No rattling at all, even at super high SPL. They're bolted onto unistrut, which is then fastened to the steel beams in the ceiling. Solid as a rock.
LOVE learning so much about sub arrangement from your videos. I run small local shows, and I run the KS212C's, which are incredible for easy cardioid setup and mitigating stage noise. I'm curious if it would be worthwhile in smaller rooms that are longer than they are wide, if it would be beneficial to split those subs that 5.5 feet to narrow the overall pattern to minimize wall bounce? Is it worth it? Also, if I were to split them, would they need to be centered? Or can I just aim them towards center? Thanks for everything you do on here!
Hey, Ben. Great questions here!
With a pair of KS212C's in a long, narrow room I would do exactly what you mentioned: put them 5 1/2 feet apart in the center in front of your stage. The caveat here is that an active cardioid setup needs space from boundaries besides the floor to work properly. So this would only work if your stage does not have a hard front. If you've got an open stage front I'd still put your subs at least 3ft downstage of your stage to help get even more cancellation at the rear.
@@MichaelCurtisAudio Thanks a bunch! If I am stuck to a hard stage front, I feel like the next best thing is stacking them together on stage to one side? If I had the horizontal space I could still do the split setup, but I'm curious if it would just make an odd pattern if they're off center?
Love this. What modeling software do you use for initial proof of concept? Is it manufacturer specific?
Thanks, Chris! EASE Focus 3 is what I used for putting the whole design together, which supports many different manufacturer's products. I used MAPP 3D from Meyer Sound to show the illustrations.
I’ve always been told, and certainly felt like, subs on the floor, coupled to that surface, made the low end more…felt, for lack of a better word. Based on this design, do you believe there is any loss in “thump”, especially that 60hz-ish kick?
No loss at all! The church I worked with on this sub setup made it very clear that they alllll about the low end. It had to hit hard, especially in the 40-80Hz octave. And this system definitely delivered! If anything flying subs makes sure that more of the audience is able to "feel" the subs, not just the front row.
@@MichaelCurtisAudio very interesting. Can’t believe I’ve just now found your channel. I lead the production team at a church in Bentonville so I’ll likely be giving you a holler!
The ceiling deck is also a boundary. In new construction I have requested a concrete pad on the roof deck to improve the response of ceiling mounted subs.
Fire!!! 🤌🏾
I'll take it!
Hey, thanks for this info but i cant download the spreadsheet
Shoot me an email and I can get you a different link.
Very unconventional and interesting
Thank you very much!
👏👏👏
wow awesome
Thank you!
How was rigging approved? Afaik SRX728 is not rated to be flown.
Rigging was approved by the integrator. I set up my engagements where I give them where I'd LIKE to have speakers, then they run the necessary calculations to approve that. You're right that those subs aren't rated to be flown with any conventional hardware from JBL, but it doesn't mean that they can't be secured in the air by other means. The unistrut cage and lag bolts solution used was a very sturdy solution.
I've never heard that subs facing each other would damage drivers. I've seen several setups from seasoned experts at Meyer Sound with similar setups. Do you have a specific resource or article you can point me to that says otherwise? I'm very curious.
@@MichaelCurtisAudio I'm trying to find the article in question in regards to the driver damage statement. I could likely be mistaken. Since that's the case, I'm going to remove that part of my comment as to not spread misinformation.
@@baileylukens No worries at all! thanks for the update.
How did you deal with the rattling noise of the roof?
The roof never rattled.
RELAY? or delays
It depends on the situation. In this video the VRX hangs in the tunnel are relays - they're covering a completely separate zone which the main PA "hands off" coverage to.
Is there gonna be an issue with the subs close to the roof and rattling of the roof...?
We tested it at a crazy volume and it's totally fine.
Newbie here trying to understand sub arrays. Watched a few of your videos including the ones on the inline gradient array and the inverted gradient array. The delay stack looks like an inline gradient array, but what is configuration of the main stack with the boxes facing each other?
Great question, Terry. The main stack is the same thing as inline gradient, but the boxes are facing each other so that their acoustic centers are close together. This makes the pattern wide. If the boxes are farther apart the coverage pattern starts to narrow, which is what I don't want with a wide audience to cover.
Thanks Michael. So is the way to think of the two boxes facing each other is they act as one box in an inline gradient array? So the front two boxes are the front and the rear two boxes are the rear box in the simplified two box inline array in your other video?
@@terryshaw2162 Yes, that's exactly it!
It's starting to make sense now. Thank you! On a slightly different topic, I recently saw on the Billie Eilish tour, the subs were hung in a vertical array directly behind the main array (L-R configuration). Big L-Accoustics setup. Could you perhaps do a video on this sort of setup? It didn't make a lot of sense to me, but obviously I'm missing something.
PS Love your videos - learning so much.
@@terryshaw2162 Having a longer line for the subs to be in actually helps narrow their coverage and make it more even front to back!
How would I array 3 jbl dual 18’s to get a cardiod pattern or can you?
If it's a wide room, i would stack them up vertically. The top facing forward, the middle facing backward, and the bottom facing forward. If it's narrow, I would place them in a horizontal line to narrow the coverage.
@@MichaelCurtisAudio unfortunately we don’t have the height to stack them the stage is not tall enough but it is a wide room. The space in front of the stage is 100’x60’. Flying up high could be an option as we have high ceilings but they don’t have the money at the moment to do that so we are stuck with them on the ground. We also don’t have to use all 3 if it’s not the best fit.
@@michaelyoung7911 Best scenario would be to fly them over the center of the stage once you get budget. If not, I would do a two-element inverted gradient stack. Just like the three-box array I mentioned, but the bottom one facing forward and top facing back. If that's too high, then I would just put them facing each other on the ground with a 4-6" space in between them.
@@MichaelCurtisAudio yeah our stage isn’t high enough to stack any :( so we will look into your last option. One of our pastors did ask if it would be easier to add a 4th box. I’m gonna have to download these prediction programs and start figuring this out! Thank you!
subs on the roof increase gravity? lol
Did I say that :D?!?