What's up Everyone.
I have recently purchased a new FOH System. I have it up and running, but don't think that I have even scratched the surface on it's capabilities. Here is the gear list...
board - A&H Mixwizard3 16:2
amps - Crown XTI 4002 (2)
mains - JBL SRX 725 (2)
subs - JBL SRX 718S (2)
signal processer - dbx driverack pa+, bbe sonic maximizer 882i
I guess what my question is, how do I set this up to where I can run the signal of my kick drum and bass to just the subs, while having guitars and vocals in the mains?
The DBX Driverack PA+ states that it is a multi-functional tool (crossover, eq, compressor, limiter, synth, etc, but I can't seem to understand how to use any/all of these features.
Anyway, any/all help would be much appreciated.
Thanks,
LW
I have recently purchased a new FOH System. I have it up and running, but don't think that I have even scratched the surface on it's capabilities. Here is the gear list...
board - A&H Mixwizard3 16:2
amps - Crown XTI 4002 (2)
mains - JBL SRX 725 (2)
subs - JBL SRX 718S (2)
signal processer - dbx driverack pa+, bbe sonic maximizer 882i
I guess what my question is, how do I set this up to where I can run the signal of my kick drum and bass to just the subs, while having guitars and vocals in the mains?
The DBX Driverack PA+ states that it is a multi-functional tool (crossover, eq, compressor, limiter, synth, etc, but I can't seem to understand how to use any/all of these features.
Anyway, any/all help would be much appreciated.
Thanks,
LW
Most engineers run the subs off a post fader aux to do exactly what you are wanting to do- keep all the stuff out of the subs that really doesn't need to be there.
Unfortunately the driverack only has two inputs, so you can't use it to process the subs if you are running the tops stereo. You could use the Processing in the Xti, it would just take a little longer to get them dialed in as far as allignment goes. Depending on the types of gigs you do, you may or may not need to tweak the allignment every time.
Try the BBE and see what you think. Personally I'm not a big fan of them. YMMV of course.
Unfortunately the driverack only has two inputs, so you can't use it to process the subs if you are running the tops stereo. You could use the Processing in the Xti, it would just take a little longer to get them dialed in as far as allignment goes. Depending on the types of gigs you do, you may or may not need to tweak the allignment every time.
Try the BBE and see what you think. Personally I'm not a big fan of them. YMMV of course.
Thanks for the reply. Is there another piece of equipment that I can add to my rack to accomplish what I am trying to do? We are a 4 piece band that travels regionally and play venues that hold from 300-800. I really want to hear the thunder from the kick, I know the system is capable of producing it, but I am obviously not running it correctly...
Hi,
Well you could add another DRPA to handle subs and that would also work. What you lack is a way to do the low pass crossover and time allignment for the subs off an aux. The Xti has both built in so the solution could be there, but if you would prefer to have the ability to tweak from FOH you would need a seperate processor.
Well you could add another DRPA to handle subs and that would also work. What you lack is a way to do the low pass crossover and time allignment for the subs off an aux. The Xti has both built in so the solution could be there, but if you would prefer to have the ability to tweak from FOH you would need a seperate processor.
Whats wrong with just setting it up normally?
By that I mean run all your mics into the main board, go from the board to the drive rack, driverack to amps, amps to speakers and subs. Just use the onboard crossover on the driverack to make sure all the bass goes to the sub.
Sure you will have a bit of the guitars in the subs and a tiny bit of kickdrum in the mains but as long as it's set up right that shouldn't risk any damage.
Of course if your intent is to have absolutely no bleed through between the subs and mains then that set up wouldn't do it.
As imix said the easiest way to do it setup wise would be to just run the mic on the kick bass directly to the sub amp. The only problem with that is you couldn't control those levels from the board...
Another way you could do it which would give you levels control is... (i like this one)
Go from all of of your instruments to the board, including the kick drum. Configure the drum onto one of the aux outputs, or use its direct output (whichever way allows you to not have that channel in the master mix) to go to the subwoofer amplifer. Then you go from the main outs to the driverack, main amps, etc. Then you can control the levels of everything at the board and have no crosstalk between the subs and mains. As long as the board allows you to use the direct or aux out while not mixing that channel in with the mains this should work, the board I've used at church (a beauty) let you do this if I remember right. That is the way I would try to set it up first, plus you don't need anymore hardware, just set it up now and see what you can do
What do you think?
By that I mean run all your mics into the main board, go from the board to the drive rack, driverack to amps, amps to speakers and subs. Just use the onboard crossover on the driverack to make sure all the bass goes to the sub.
Sure you will have a bit of the guitars in the subs and a tiny bit of kickdrum in the mains but as long as it's set up right that shouldn't risk any damage.
Of course if your intent is to have absolutely no bleed through between the subs and mains then that set up wouldn't do it.
As imix said the easiest way to do it setup wise would be to just run the mic on the kick bass directly to the sub amp. The only problem with that is you couldn't control those levels from the board...
Another way you could do it which would give you levels control is... (i like this one)
Go from all of of your instruments to the board, including the kick drum. Configure the drum onto one of the aux outputs, or use its direct output (whichever way allows you to not have that channel in the master mix) to go to the subwoofer amplifer. Then you go from the main outs to the driverack, main amps, etc. Then you can control the levels of everything at the board and have no crosstalk between the subs and mains. As long as the board allows you to use the direct or aux out while not mixing that channel in with the mains this should work, the board I've used at church (a beauty) let you do this if I remember right. That is the way I would try to set it up first, plus you don't need anymore hardware, just set it up now and see what you can do
What do you think?
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I have a hard time seeing why you would ever isolate bassguitar and kick-drum from the top. It will not sound very good. I have tried lot's of FOH's in my career, and have never seen anyone sending the kick drum or any other intrument just to the subs, or just to the top system.
If you don't know how to use compressor and limiter, then first try to disable them. If not used correctly they will mess up totally. Normally I would have seperate comps/gates/limiters on sub groups, and if sub groups are not available then on inserts. If the comp/gate/limiter works heavily on main out, then you will have a hard time to have good sound.
If you don't know how to use compressor and limiter, then first try to disable them. If not used correctly they will mess up totally. Normally I would have seperate comps/gates/limiters on sub groups, and if sub groups are not available then on inserts. If the comp/gate/limiter works heavily on main out, then you will have a hard time to have good sound.
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Just for clarification- most engineers that run aux fed subs do not usually isolate those instruments from a passband. Nor are the instrument run directly to the amps.
It's all about control. You can use the tops for the attack and the subs for the thump and have control over how much of each. Same goes for any channel that may be feeding the sub aux.
The key to it sounding as good as it can is setting the crossover point and slope for both correctly. High pass for the tops and low pass for the subs. You also want the two elements time aligned so both sources arrive at the same time. (of course it's an average as it can really only be aligned at one single point at a time)
It's all about control. You can use the tops for the attack and the subs for the thump and have control over how much of each. Same goes for any channel that may be feeding the sub aux.
The key to it sounding as good as it can is setting the crossover point and slope for both correctly. High pass for the tops and low pass for the subs. You also want the two elements time aligned so both sources arrive at the same time. (of course it's an average as it can really only be aligned at one single point at a time)
Ok, but I still don't see the benefit. I just use the low cut or shelving eq, I don't want vocals or guitar in the sub. I'd rather use the sub groups for other purposes, since most of the times I have 4 sub groups and if I'm lucky I have 8
Sorry, it's the slack terminology that gets confusing. I am only talking about running the signal to the subwoofers off of an aux send. Not having subgroups anywhere in this equation.
You could use a subgroup of course, but a better solution for that need would be to use a matrix off the console if available. That's how large theater rigs are often run. It's not unusual for the stereo fader to go unused in that case.
But, for the OP needs an aux is a good way to do it.
You could use a subgroup of course, but a better solution for that need would be to use a matrix off the console if available. That's how large theater rigs are often run. It's not unusual for the stereo fader to go unused in that case.
But, for the OP needs an aux is a good way to do it.
Still waiting to hear from lwilliams28.
It would be nice to hear excactly what you are after, and how you have done it so far. And maybe two 18" suba is a little underrated for 300-800 people. It depends on the musicstyle and how loud you are playing (and a lot of other factors).
imix500: Off course an aux send could be used, but again - very often you have very limited numbers of sends to use. They will often be divided in pre and post sends (if you are lucky you will be able to switch between those). You will use some for stage monitor and the rest for effects. I think you are used to very large set-ups with unlimited possibilities, and I bet you also have gate and comps build into the console on every channel
I still don't see why sending to subs instead of using low cut is better sonically.
It would be nice to hear excactly what you are after, and how you have done it so far. And maybe two 18" suba is a little underrated for 300-800 people. It depends on the musicstyle and how loud you are playing (and a lot of other factors).
imix500: Off course an aux send could be used, but again - very often you have very limited numbers of sends to use. They will often be divided in pre and post sends (if you are lucky you will be able to switch between those). You will use some for stage monitor and the rest for effects. I think you are used to very large set-ups with unlimited possibilities, and I bet you also have gate and comps build into the console on every channel
I still don't see why sending to subs instead of using low cut is better sonically.
OP is MIA so it's hard to know if he has some extenuating circumstances. But barring anything unusual, I would argue that it's not better sonically, if anything worse.
If the OP's idea is to run both the subs and the mains full range but only have bass guitar and drums to the sub, and everything else to the mains, then I would strongly advise against it. A guitarist slapping the strings can create signal in the single digit frequency range that without an adequate high pass could destroy drivers easy with relatively low power.
It seems that this whole thing may be as simple as the OP not understanding that the crossover in the driverack does exactly what he wants, but I have no idea of his experience level. Considering that he just bought the system it could be low but I don't want to jump to conclusions.
I would agree with this. I am building a system for a high school football stadium starting in just over a week. I am going to do 4 18" horns (TH-18s) that will just be cutting it, looking at the numbers. And there's no way you get more output from those bass reflex cabs then the horns, with very efficient, high excursion B&C drivers...
For the mains I'm building 4 DR250s, a bit under rated theoretically but at the levels they use at the stadium they should do fine. I can't recall the exact numbers, they're written with my notes, but the system output max was around 138dB @1 m. That could be off by a few dB
Kjeldsen
I appreciate all of the feedback on here. For the last 3 months that I have had this system, I have just set up all of the presets on the DRPA+, selected the speakers that I am using, into the BBE 882i, into the board. (i may have said that incorrectly, but you know what i mean). everything is loud, but it is just a bit muddy. I believe what I am trying to do is to run an aux fed sub system so I can send the channels that i want directly to the subs, while the rest go to the tops. The board that I have (A&H MW3 16:2) is capable and set up to where this is an option. Aux 6 comes with an independent fader next to the LR Main faders. This fader gives you control of how much output the sub has and then by adjusting the aux 6 level across the board you can control what goes to it. I am just having a little bit of difficulty learning where the cables need to be run to to make this happen.
I appreciate all of the feedback on here. For the last 3 months that I have had this system, I have just set up all of the presets on the DRPA+, selected the speakers that I am using, into the BBE 882i, into the board. (i may have said that incorrectly, but you know what i mean). everything is loud, but it is just a bit muddy. I believe what I am trying to do is to run an aux fed sub system so I can send the channels that i want directly to the subs, while the rest go to the tops. The board that I have (A&H MW3 16:2) is capable and set up to where this is an option. Aux 6 comes with an independent fader next to the LR Main faders. This fader gives you control of how much output the sub has and then by adjusting the aux 6 level across the board you can control what goes to it. I am just having a little bit of difficulty learning where the cables need to be run to to make this happen.
I might have an idea why its muddy.
Even though pass guitar and kick drum has fundamentals in the sub range, there are many over tones that will be quite a ways out of the passband. The bass guitar could sound muddy because the overtones which give it a sense of clarity are not being produced well by the sub.
If you want to have those instruments only going to the sub then I would also send them to the mains, with a high pass filter. that way the overtones are being handled by the mains but the fundamentals are done by the sub
Just a thought...
Even though pass guitar and kick drum has fundamentals in the sub range, there are many over tones that will be quite a ways out of the passband. The bass guitar could sound muddy because the overtones which give it a sense of clarity are not being produced well by the sub.
If you want to have those instruments only going to the sub then I would also send them to the mains, with a high pass filter. that way the overtones are being handled by the mains but the fundamentals are done by the sub
Just a thought...
Two simple solutions to try.
1) Loose the BBE. They really don't do anything musically useful at the bottom end in a PA situation.
2) Dial in a bit of EQ on the driverack. A 3db or so boost at 100/120 Hz will clear things up no end. Or you could try a first order HPF starting at about 60Hz. You really don't need to go that low for a guitar band.
1) Loose the BBE. They really don't do anything musically useful at the bottom end in a PA situation.
2) Dial in a bit of EQ on the driverack. A 3db or so boost at 100/120 Hz will clear things up no end. Or you could try a first order HPF starting at about 60Hz. You really don't need to go that low for a guitar band.
I'm not shure if the system as a whole can do what you wan't, and its not nescesary. Just set it up normally. The subs are intented do be crossed at 80 Hz and low cut are also normally 80 Hz, so this will give you the same effect.
Instead you need to ensure that you have no low freq feedback from mic's. Gain is important here, and also placement of mic's and selecting the correct mic's. You should not be able to here people walking around on the stage. If so, gain and possible low freq is overall to high (or you could have an issue with a compressor). When you are satisfied you can begin with some gates, but the fundamentals shall always be in order first. Also make sure you don't just raise the eq points to the sound you prefer. Lowering an eq point can be much more effective. Try lowering 200 Hz in the FOH mix, and do not define kick drum, low toms and bass in the same region (in low freq area). Also cut everything below 40 Hz. low cut everything that do not need deep bass.
Thank you I understand that thats where the sub is crossed usually. I have built quite a few systems and designed even more.
From wikipedia - "An overtone is any frequency higher than the fundamental frequency of a sound"
I was using the word interchangeably with harmonics. Ever instrument will have its own distinct harmonic signature, that is it will have many harmonics above the fundamental. Therefore even a bass guitar which has a low fundamental frequency has to be reproduced on a full range system, not just a subwoofer. I know that a bass guitar can have fundamentals also above 80hz, depending on the note being played of course, which makes my suggestion even more valid.
By that I meant that he needs to have both the guitar and kickdrum going to both the mains and the sub so that they will be reproduced full range, as opposed to just the sub as the OP seemed to be suggesting.
The SRX725 has a fair frequency range and power handling.
The SRX718S subwoofer crosses over at a fairly low frequency.
If the venue was suitable I would stack the two subwoofers to couple their output (gaining some extra volume for free!). The best performance for this system will only be realised when the Driverack is configured properly to run the speakers as an active system. The subwoofers are not designed to take a full range signal. Their function in the system is to reduce the frequency range that the mid tops are required to reproduce.
The Kick drum and Bass guitar have a wide frequency range and need to be reproduced by the complete active system. The way to stop the rest of the Band instruments from being reproduced by the subs is to use the HPF buttons that are on each channel of the Allen & Heath mixer - These filter out all frequencies below 80Hz virtually eliminating them from the subs.
LW you need to take some time to figure out how to set up the Driverack to configure it as a 2 way active crossover. Getting this configured correctly is the key to getting the best performance from the system you have.
The SRX718S subwoofer crosses over at a fairly low frequency.
If the venue was suitable I would stack the two subwoofers to couple their output (gaining some extra volume for free!). The best performance for this system will only be realised when the Driverack is configured properly to run the speakers as an active system. The subwoofers are not designed to take a full range signal. Their function in the system is to reduce the frequency range that the mid tops are required to reproduce.
The Kick drum and Bass guitar have a wide frequency range and need to be reproduced by the complete active system. The way to stop the rest of the Band instruments from being reproduced by the subs is to use the HPF buttons that are on each channel of the Allen & Heath mixer - These filter out all frequencies below 80Hz virtually eliminating them from the subs.
LW you need to take some time to figure out how to set up the Driverack to configure it as a 2 way active crossover. Getting this configured correctly is the key to getting the best performance from the system you have.
Well I am one of those guys who likes to do a separate subwoofer feed. You set up the subs to be fed from a post fade aux send. (Or a separate group feed when you have it.)
Now for normal full range inputs you set the aux send for unity gain. That way as you fade the channel up and down it behaves exactly like a full range system. When you have something that you want to have extra LF energy you turn down the gain trim and the aux send up. You can even tweak the EQ. So the channel fader works like normal but has more LF.
The other end is when you have a singer that you want less bass from, you just dial down the subwoofer aux send.
Now if you want to do this you need to have at least three inputs (four is better) and you set the system up for your favorite house curve. Too many folks use an analyzer and set the system flat, without understanding the difference between continuous noise and music. (But that may depend on the band!)
A typical band EQ curve would put in an octave wide bump at 150 hz. and again at 4-6 Khz.
The microphone with the most gain should be all the same types. That way a few cuts will get out most of the feedback.
Of course we didn't mention monitors.
Now for normal full range inputs you set the aux send for unity gain. That way as you fade the channel up and down it behaves exactly like a full range system. When you have something that you want to have extra LF energy you turn down the gain trim and the aux send up. You can even tweak the EQ. So the channel fader works like normal but has more LF.
The other end is when you have a singer that you want less bass from, you just dial down the subwoofer aux send.
Now if you want to do this you need to have at least three inputs (four is better) and you set the system up for your favorite house curve. Too many folks use an analyzer and set the system flat, without understanding the difference between continuous noise and music. (But that may depend on the band!)
A typical band EQ curve would put in an octave wide bump at 150 hz. and again at 4-6 Khz.
The microphone with the most gain should be all the same types. That way a few cuts will get out most of the feedback.
Of course we didn't mention monitors.
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