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[Sam Costa]

Hello everyone,
Hoping to see if someone could chime in on whether or not this would be the optimal sub placement for most of the shows I run.

80% of the shows I'll be deploying 2 - Dual 18" sub cabinets per side (passive Carvin TRX218n) Traditionally I've been floor stacking these on carts I've build for ease of in/out transport of venues. Also, traditionally with the mains stacked on top with either 1 or 2 KF650's per side depending on the width of the venue and coverage needed.

I do notice the "power alley" when deployed in this manner, but being that I've got 4 dual 18" sub cabs available, would it be a better solution so that I get more constant sub coverage on a dance floor by placing all the subs directly in front of the stage on the floor or keep them to the side (as shown) as I typically do and get additional subs placed in the middle (between the two stacks) ? a lot of these shows there are people dancing directly in front of the stage and I'm just trying to make it sound as best as possible for the audience dancing.

Running all my networking through EAW UX3600, it sounds great but would like to see if there is a better way of deploying subs for better coverage.

1- QSC PL6.0 on subs
1- QSC PL4.0 on lows
1- QSC 4.0 on mids,
1- QSC 3204 on highs

I also fly the mains on certain events so they are well above everyones head for larger venues and the subs stay stacked directly below the mains.

Here's a pick of a recent show a few months ago..  It sounded good but did notice some area along the front where the sub wasn't as coherent and thumping on your chest. The correct splay was used on the mains for the KF650's and those sounded great in all areas of the dance floor.

[Miguel Dahl]

Hello everyone,
Hoping to see if someone could chime in on whether or not this would be the optimal sub placement for most of the shows I run.

80% of the shows I'll be deploying 2 - Dual 18" sub cabinets per side (passive Carvin TRX218n) Traditionally I've been floor stacking these on carts I've build for ease of in/out transport of venues. Also, traditionally with the mains stacked on top with either 1 or 2 KF650's per side depending on the width of the venue and coverage needed.

I do notice the "power alley" when deployed in this manner, but being that I've got 4 dual 18" sub cabs available, would it be a better solution so that I get more constant sub coverage on a dance floor by placing all the subs directly in front of the stage on the floor or keep them to the side (as shown) as I typically do and get additional subs placed in the middle (between the two stacks) ? a lot of these shows there are people dancing directly in front of the stage and I'm just trying to make it sound as best as possible for the audience dancing.

Running all my networking through EAW UX3600, it sounds great but would like to see if there is a better way of deploying subs for better coverage.

1- QSC PL6.0 on subs
1- QSC PL4.0 on lows
1- QSC 4.0 on mids,
1- QSC 3204 on highs

I also fly the mains on certain events so they are well above everyones head for larger venues and the subs stay stacked directly below the mains.

Here's a pick of a recent show a few months ago..  It sounded good but did notice some area along the front where the sub wasn't as coherent and thumping on your chest. The correct splay was used on the mains for the KF650's and those sounded great in all areas of the dance floor.

You can space them equally along the width of the area to cover to get somewhat rid of the power-alley. If the area is wide you'd maybe want to delay the two outer ones. But, can you place them in front of the stage? Is it room, is it ok to eat up some floor space? You'd also need something to support the tops if you move the subs.

You can also angle the subs slightly outward to get less of a drastic power-alley. It will still be there, but the difference will be a bit smaller between the alley and a negative lobe.

If people are drinking and just dancing I'd go with that setup in the pic. It makes your loadout easier, doesn't eat up floorspace and people at a certain point in the night really don't care, they just want to dance, drink and have fun. They'll dance in and out of lobes.

[Tim McCulloch]

Any time you space multiple radiators of identical signals you will get comb filtering; the smaller the distance the higher the frequency...

Miguel puts it nicely - if the punters don't think it's an issue; if your client isn't birthing live kittens because she hates power alley... you can safely direct your mental energies towards something that creates a new line item on the invoice...

Why do I say that?  Because of my first sentence.  You can space the subs (1/4 wave length of the acoustic crossover freq, from acoustic center to acoustic center of each sub) and get some decent horizontal uniformity at the expense of coverage past the ends of the array and also dumping close to 50% of your sub energy right up on the stage.  For some acts this could be very good but could be very distracting for others.   What you "fix" for part of the audience you may well hose for another part (or worse, the band).  Everything in audio is a compromise and has consequences; experiment and find the counter-intuitive "gotchas!" or leave it be and enjoy the simplicity of your load in and set up.

Too bad that tent is blue and yellow stripes.  Were it plain white you could up-sell atmospheric lighting treatments for the top & sides, sponsor logo gobo projection...

How did you arrive at the splay between the KF650s in the pic?  They seem closer together than the 650s in my memories.

[Sam Costa]

You can space them equally along the width of the area to cover to get somewhat rid of the power-alley. If the area is wide you'd maybe want to delay the two outer ones. But, can you place them in front of the stage? Is it room, is it ok to eat up some floor space? You'd also need something to support the tops if you move the subs.

You can also angle the subs slightly outward to get less of a drastic power-alley. It will still be there, but the difference will be a bit smaller between the alley and a negative lobe.

If people are drinking and just dancing I'd go with that setup in the pic. It makes your loadout easier, doesn't eat up floorspace and people at a certain point in the night really don't care, they just want to dance, drink and have fun. They'll dance in and out of lobes.

Thanks for the info. I do have the means of "flying" the mains via trussing and flyware/slings which I already do on some events/shows.
Typically around 300-500 people shows up for these events (Portuguese festivals) so I want to make the best for the audience in attendance.

Most of these events happen in large halls and a few per year in large tents as shown. I typically do have plenty of room along the front of the stage area, the other problem of course is people jumping up on the sub cabs and dancing once they've had too much of the Portuguese moonshine or wine, but you're right, they do love to drink and at some point anything sounds good. lol

There is the occasional show where we play for audiences where we install a 10'ft catwalk so I always have to be aware of where the audience will be dancing or listening, a lot of times they end up coming right to the stage which isn't exactly the greatest area for listening in which I've deployed front fills so they can atleast sing along and hear properly.

Thank you again for your input, I appreciate it.

[Sam Costa]

Any time you space multiple radiators of identical signals you will get comb filtering; the smaller the distance the higher the frequency...

Miguel puts it nicely - if the punters don't think it's an issue; if your client isn't birthing live kittens because she hates power alley... you can safely direct your mental energies towards something that creates a new line item on the invoice...

Why do I say that?  Because of my first sentence.  You can space the subs (1/4 wave length of the acoustic crossover freq, from acoustic center to acoustic center of each sub) and get some decent horizontal uniformity at the expense of coverage past the ends of the array and also dumping close to 50% of your sub energy right up on the stage.  For some acts this could be very good but could be very distracting for others.   What you "fix" for part of the audience you may well hose for another part (or worse, the band).  Everything in audio is a compromise and has consequences; experiment and find the counter-intuitive "gotchas!" or leave it be and enjoy the simplicity of your load in and set up.

Too bad that tent is blue and yellow stripes.  Were it plain white you could up-sell atmospheric lighting treatments for the top & sides, sponsor logo gobo projection...

How did you arrive at the splay between the KF650s in the pic?  They seem closer together than the 650s in my memories.

Hi Tim, thanks for chiming in, always appreciated.
I think I'm just being too sensitive and overthinking that whole process. For these particular shows, I'm on stage (keyboards) so I don't get to hear what the audience is listening too, I leave that up to our FOH engineer of course, but it's all my gear and want to make sure it's done properly and sounding great for those attending.

The splay was actually with some research, some of which were on these forums somewhere. If and when I have 2 main cabs (KF650's) I use the "fist" method in between them, which I believe translates to 5-7 degrees?.. I could be wrong but I did play with that a few times during sound check and it does sound slightly better with not much overlapping between the two cabs.

Believe me, if it were up to me, It would have had a nice black velvet curtain along the entire back... I'm guessing the committee of the hall got a GREAT deal on that tent because of those colors. lol

[David Sturzenbecher]

It's been 10 years since I last touched a 650 rig, but these were the angles I used at the time.


Sent from my iPhone using Tapatalk Pro

[Tim McCulloch]

It's been 10 years since I last touched a 650 rig, but these were the angles I used at the time.


Sent from my iPhone using Tapatalk Pro

My memory was "3 fists" between the front of the 650s, which for me is about 12".

[Sam Costa]

It's been 10 years since I last touched a 650 rig, but these were the angles I used at the time.


Sent from my iPhone using Tapatalk Pro

I must have big fists cause I had it about 6" apart. LOL
I actually have this drawing on my phone and always good to have on hand.
Thank you!

[ProSoundWeb Community]