Best way to run tops & subs

[ian hatch]

Hi all

Just taken delivery of a new active PA, consisting of 2 tops & 2 subs and was wondering what is the best way of running them.

Option 1:

Main outs from the desk to the subs, then out from the subs to the tops with the 80Hz filter buttons pressed in.

Option 2:

Main outs from the desk to the tops, with the 90Hz buttons pressed in, then use the MONO out feed from the desk (GL2400) to feed the sub/subs(depending on size of gig)

My main question is, what are the pros/cons with either option.

The only advantage I can think of, is in option 2 you can control the bass volume, but do you lose any sound quality with this option compared with option 1.

 

All advice greatly received.

Ian

[stagemanagement]

Hi all

Just taken delivery of a new active PA, consisting of 2 tops & 2 subs and was wondering what is the best way of running them.

Option 1:

Main outs from the desk to the subs, then out from the subs to the tops with the 80Hz filter buttons pressed in.

Option 2:

Main outs from the desk to the tops, with the 90Hz buttons pressed in, then use the MONO out feed from the desk (GL2400) to feed the sub/subs(depending on size of gig)

My main question is, what are the pros/cons with either option.

The only advantage I can think of, is in option 2 you can control the bass volume, but do you lose any sound quality with this option compared with option 1.

 

All advice greatly received.

Ian

 

If the mid/hi boxes have a facility to link to the sub, with an output from the back of them, then they will receive your main desk outputs and then link to the subs with the crossover point as per manufacturers recommendation.

 

If the mid/hi boxes don't have that, then you need to get a stereo 2-way crossover unit and send the main outs from the desk into that and take outputs from that to each of the mid/hi boxes and the subs seperately; and then play with the crossover frequency setting on the unit until you get satisfactory results - I'd suggest starting at 120Hz, with everything below that going to the subs and above that going to your mid/hi boxes.

[smalljoshua]

What PA system is it? You may also be able to go from desk to subs, then from the subs into the tops via the crossover in the subs.

 

Josh

[MarkPAman]

It would be good to know what system this is, though I think Ian's already told us he can run desk - subs - tops & that there's a crossover in the subs (option 1). This is what I'd probably do most of the time - but see option 3 :)

 

With option 2 - you say the tops have a 90Hz filter, but it seems the subs crossover is 80Hz. This leaves a small gap which may or may not be a problem.

 

If that's not a problem, then I give you option 3:

 

Tops from main L+R & subs from a post fade aux, meaning you can clean up the bottom end by only sending stuff that needs it to the subs. Lots of instuments have nothing useful happening that low.

[ian hatch]

It would be good to know what system this is, though I think Ian's already told us he can run desk - subs - tops & that there's a crossover in the subs (option 1). This is what I'd probably do most of the time - but see option 3 :** laughs out loud **:

 

With option 2 - you say the tops have a 90Hz filter, but it seems the subs crossover is 80Hz. This leaves a small gap which may or may not be a problem.

 

If that's not a problem, then I give you option 3:

 

Tops from main L+R & subs from a post fade aux, meaning you can clean up the bottom end by only sending stuff that needs it to the subs. Lots of instuments have nothing useful happening that low.

 

Cheers for the replies.

 

Mark, I'm guessing from your option 3 that the advantage over my option 2(mono send) is, the mono send just sends everything from the desk and the crossover has to do all the work. (sound wise not as good as option 1?)

The reason I mentioned option 2 was, at some small gigs 2 subs are overkill or there's not enough room for 2 but the tops are just not quite right on their own.

I think under normal conditions then option 1 is the way to go.

So you would control the bass volume from the AUX MASTER?

Also I forgot to mention the subs have 2 filter settings 80+100Hz, so would I be better having them set to 100Hz?

 

Ian

[mervaka]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

[ian hatch]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

The GL2400's mono send is just LR summed together, I think?

The tops have a 90Hz cut button and the subs have 2, 1 @ 80Hz + 1 @ 100Hz

How best to set the Aux.

[mervaka]

ooh, I missed that bit of information! a GL2400 can run either LR sum or aux6 off its mono fader, but it doesnt have a mono bus. the other GLs do!

[stagemanagement]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

The GL2400's mono send is just LR summed together, I think?

The tops have a 90Hz cut button and the subs have 2, 1 @ 80Hz + 1 @ 100Hz

How best to set the Aux.

 

As merv says, you can set up your desk so that Aux 6 can be run with the mono fader; but this doesn't offer anything different than running through the rotary master apart from having a fader instead of a knob.

 

As for the cuttoff between sub and top, if the top's roll off at 90Hz (and it's a shelf rather than a straight cutoff), then I'd set the subs at 80Hz, that way they should be crossing over slightly but not at full level; effectively giving you a slight notch between 80 and 90Hz - which can tidy up the sub no end, taking out some of the mud!!

[ian hatch]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

The GL2400's mono send is just LR summed together, I think?

The tops have a 90Hz cut button and the subs have 2, 1 @ 80Hz + 1 @ 100Hz

How best to set the Aux.

 

As merv says, you can set up your desk so that Aux 6 can be run with the mono fader; but this doesn't offer anything different than running through the rotary master apart from having a fader instead of a knob.

 

As for the cuttoff between sub and top, if the top's roll off at 90Hz (and it's a shelf rather than a straight cutoff), then I'd set the subs at 80Hz, that way they should be crossing over slightly but not at full level; effectively giving you a slight notch between 80 and 90Hz - which can tidy up the sub no end, taking out some of the mud!!

 

Thanks for the reply.

 

It looks like I'm going to have to run the seperate sub straight through the mono out because the band has acquired a Delay unit to run along side our FX unit, so I've run out of Aux's. (4 monitors 2 fx & delay)

I'm glad you confirmed the Xover points, they are what I was going to run, but I wanted to double check them.

Little OT question,

I normanly run the system 90% of the time as follows, (not like the original question, venue dictates that set-up) main outs to the subs (80Hz Xover set on subs) then subs to tops (no filter) on poles, but should I really be running the subs with the 100Hz Xover instead of 80Hz, to take the work load off the tops?

Also does it make any difference if the gig is indoors or out(marquees)?

(System RCF TT18A Subs & TT22A Tops)

Cheers

Ian

[bassfreak]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

The GL2400's mono send is just LR summed together, I think?

The tops have a 90Hz cut button and the subs have 2, 1 @ 80Hz + 1 @ 100Hz

How best to set the Aux.

 

As merv says, you can set up your desk so that Aux 6 can be run with the mono fader; but this doesn't offer anything different than running through the rotary master apart from having a fader instead of a knob.

 

As for the cuttoff between sub and top, if the top's roll off at 90Hz (and it's a shelf rather than a straight cutoff), then I'd set the subs at 80Hz, that way they should be crossing over slightly but not at full level; effectively giving you a slight notch between 80 and 90Hz - which can tidy up the sub no end, taking out some of the mud!!

 

Thanks for the reply.

 

It looks like I'm going to have to run the seperate sub straight through the mono out because the band has acquired a Delay unit to run along side our FX unit, so I've run out of Aux's. (4 monitors 2 fx & delay)

I'm glad you confirmed the Xover points, they are what I was going to run, but I wanted to double check them.

Little OT question,

I normanly run the system 90% of the time as follows, (not like the original question, venue dictates that set-up) main outs to the subs (80Hz Xover set on subs) then subs to tops (no filter) on poles, but should I really be running the subs with the 100Hz Xover instead of 80Hz, to take the work load off the tops?

Also does it make any difference if the gig is indoors or out(marquees)?

(System RCF TT18A Subs & TT22A Tops)

Cheers

Ian

 

We have the TT18's and the TT25a tops, we go from the main outs to the subs with the xover point set at 110hz.

[ian hatch]

it all depends on how you prefer to work. some people like to mix a simple LR mix, others like to control the sub separately to varying degrees.

 

option 3 allows you to only send to the subs things you want in the sub mix, such as kick and bass guitar. this effectively 'cleans up' the low end.

 

and yes, the aux master would be your sub master.

 

 

with your option 2, is the mono output just a LR sum, or has it got its own bus? if it's the latter, then it does pretty much the same job as above!

 

 

could you clarify what crossover settings the tops have? is it just 90Hz?

The GL2400's mono send is just LR summed together, I think?

The tops have a 90Hz cut button and the subs have 2, 1 @ 80Hz + 1 @ 100Hz

How best to set the Aux.

 

As merv says, you can set up your desk so that Aux 6 can be run with the mono fader; but this doesn't offer anything different than running through the rotary master apart from having a fader instead of a knob.

 

As for the cuttoff between sub and top, if the top's roll off at 90Hz (and it's a shelf rather than a straight cutoff), then I'd set the subs at 80Hz, that way they should be crossing over slightly but not at full level; effectively giving you a slight notch between 80 and 90Hz - which can tidy up the sub no end, taking out some of the mud!!

 

Thanks for the reply.

 

It looks like I'm going to have to run the seperate sub straight through the mono out because the band has acquired a Delay unit to run along side our FX unit, so I've run out of Aux's. (4 monitors 2 fx & delay)

I'm glad you confirmed the Xover points, they are what I was going to run, but I wanted to double check them.

Little OT question,

I normanly run the system 90% of the time as follows, (not like the original question, venue dictates that set-up) main outs to the subs (80Hz Xover set on subs) then subs to tops (no filter) on poles, but should I really be running the subs with the 100Hz Xover instead of 80Hz, to take the work load off the tops?

Also does it make any difference if the gig is indoors or out(marquees)?

(System RCF TT18A Subs & TT22A Tops)

Cheers

Ian

 

We have the TT18's and the TT25a tops, we go from the main outs to the subs with the xover point set at 110hz.

Thanks for that, any reason ?

Also, can you make any sense of the Xover ADD button, and have you ever tried it.

Ian

[bassfreak]

Thanks for that, any reason ?

Also, can you make any sense of the Xover ADD button, and have you ever tried it.

Ian

 

Just seemed more logical, plus the bins may as well do as much of the low end as possible.

 

If I remember rightly, reading the manual the xover add switch is to be used if the tops are being used a distance from the bins, when pressed in it reverses the phase of the tops.

[ian hatch]

Thanks for that, any reason ?

Also, can you make any sense of the Xover ADD button, and have you ever tried it.

Ian

 

Just seemed more logical, plus the bins may as well do as much of the low end as possible.

 

If I remember rightly, reading the manual the xover add switch is to be used if the tops are being used a distance from the bins, when pressed in it reverses the phase of the tops.

Cheers for that, I didn't realise it reversed the phase on the tops.

The manual refers to the tops being held with a 80Hz Xover if using the Xover ADD button, but the phase reversal does then make sense.

Have you ever used your set-up like that, if so, what was the result like?

[bassfreak]

Thanks for that, any reason ?

Also, can you make any sense of the Xover ADD button, and have you ever tried it.

Ian

 

Just seemed more logical, plus the bins may as well do as much of the low end as possible.

 

If I remember rightly, reading the manual the xover add switch is to be used if the tops are being used a distance from the bins, when pressed in it reverses the phase of the tops.

Cheers for that, I didn't realise it reversed the phase on the tops.

The manual refers to the tops being held with a 80Hz Xover if using the Xover ADD button, but the phase reversal does then make sense.

Have you ever used your set-up like that, if so, what was the result like?

 

Nah we've never had to use them like that as we have the tops on poles.