Crossover suggestions for PA

[Teebs]

I'm looking to add a single active sub cabinet to our (basic) PA setup. I realise that it is possible to either use a crossover, or 'aux out' to the sub. The existing speakers don't handle the bass too well (10" + HF horn).

The existing setup consists of the following:

The choices seem to be 'AUX OUT' - a separate mix with just bass guitar, bass drum (and anything else low) to a single active sub:

Or a crossover to separate the frequencies to the main speakers and the sub:

My question is - what do people feel is the best route - Aux Mix or Crossover?

If crossover -  does anyone recommend anything that would do what I've shown above?

Thank you in advance

[Jakester]

Another option - active subs sometimes have a built in crossover so it does the job for you from the existing full range mix. 

[Teebs]

9 minutes ago, Jakester said:

Another option - active subs sometimes have a built in crossover so it does the job for you from the existing full range mix. 

Good suggestion

Wouldn't the low frequencies still be going to the 10" speakers though?

[Jakester]

7 minutes ago, Teebs said:

Good suggestion

Wouldn't the low frequencies still be going to the 10" speakers though?

Not as I understand it - on some you set the threshold frequency and anything over that goes to the tops, and anything under goes to the subs. 

[Teebs]

Aah!

That would definitely work!

Thankyou!

[jrixn1]

32 minutes ago, Jakester said:

Not as I understand it - on some you set the threshold frequency and anything over that goes to the tops, and anything under goes to the subs. 

Make sure the sub has two inputs and two high-passed outputs, as some (many?) only have one. 

@Teebs what are your current speakers and mixer?

 

[Teebs]

It's only a small PA for an open mic night:

MIXER - Yamaha MG166cx or Yamaha MG10 (depends on who's setting up!)

SPEAKERS - Alto TX210 (active) x 2

Proposed SUB - Evolution Audio EL-SUB15a (active).

[Jakester]

7 minutes ago, jrixn1 said:

Make sure the sub has two inputs and two high-passed outputs, as some (many?) only have one. 

@Teebs what are your current speakers and mixer?

 

Yep, that one looks like it’s only one. Our Mackie has two, so we run both tops via the sub. 
Can your budget stretch to one with two thru-passes?

[Teebs]

2 minutes ago, Jakester said:

Yep, that one looks like it’s only one. Our Mackie has two, so we run both tops via the sub. 
Can your budget stretch to one with two thru-passes?

I'll have a look.

Was aiming for cheap n' cheerful, but it needs to do the job properly, so not too concerned about spending a bit more.

What is your Mackie?

[Dan Dare]

If your sub doesn't have a way of feeding the tops with a signal form which the lf has been removed, there's a basic inexpensive Behringer active crossover - see https://www.gear4music.com/PA-DJ-and-Lighting/Behringer-CX2310-V2-Pro-Super-X-Crossover/2L8L?origin=product-ads&msclkid=68517d1e9daf19f0f62f2348ed816765&utm_source=bing&utm_medium=cpc&utm_campaign=PLA Shop - Behringer&utm_term=4583795258507178&utm_content=Behringer | Everything Else.

You can pick them up used very cheaply on eBay. Not the last word, but will do the job.

[Teebs]

9 minutes ago, Dan Dare said:

If your sub doesn't have a way of feeding the tops with a signal form which the lf has been removed, there's a basic inexpensive Behringer active crossover - see https://www.gear4music.com/PA-DJ-and-Lighting/Behringer-CX2310-V2-Pro-Super-X-Crossover/2L8L?origin=product-ads&msclkid=68517d1e9daf19f0f62f2348ed816765&utm_source=bing&utm_medium=cpc&utm_campaign=PLA Shop - Behringer&utm_term=4583795258507178&utm_content=Behringer | Everything Else.

You can pick them up used very cheaply on eBay. Not the last word, but will do the job.

That looks like a good solution.

Thank you

[Teebs]

I'm leaning towards @Dan Dare's suggestion of an active crossover, but does anyone have any views on the 'Aux Out' method, where you take a line out of the mixer via 'Aux' and have a dedicated mix just for the Sub?

I realise that all frequencies are still going to the Speakers.

[mrtcat]

2 hours ago, Teebs said:

I'm leaning towards @Dan Dare's suggestion of an active crossover, but does anyone have any views on the 'Aux Out' method, where you take a line out of the mixer via 'Aux' and have a dedicated mix just for the Sub?

I realise that all frequencies are still going to the Speakers.

Depends on your mixer. Aux fed subs can be great as long as you're leaving enough auxes for monitors. If you have a master eq for the main l/r out then you can cut some lows out of the tops and only bleed a bit of kick and bass through the sub. Too much bass guitar in the subs can a pain so this way you have more control over what goes where. 

Personally I prefer aux fed subs because you have more control. 

[Teebs]

3 minutes ago, mrtcat said:

Depends on your mixer. Aux fed subs can be great as long as you're leaving enough auxes for monitors. If you have a master eq for the main l/r out then you can cut some lows out of the tops and only bleed a bit of kick and bass through the sub. Too much bass guitar in the subs can a pain so this way you have more control over what goes where. 

Personally I prefer aux fed subs because you have more control. 

Thanks @mrtcat

I didn't realise that.

I think I'll go with the crossover that DanDare suggested.

[mike257]

Aux fed subs are an oft-misunderstood approach.

Even on festival-sized rigs, you'll still not find a consensus amongst engineers as to whether or not it's a better method. 

The right way to do it is with either a fixed-level subgroup or any post-fader aux with the sends set at 0db for the channels you need sub content from (generally kick, floor tom, bass, keys and any samplers/tracks etc, as well as whatever you're playing your interval music from!). This means the content hitting the subs tracks your fader movements and stays proportional to what is hitting your tops. 

With your setup, you'd still want a crossover in line with the tops so you could filter the low end out that the sub is giving you, or you won't get the benefits that aux fed subs provide - reducing the load on your tops by stopping them fighting to reproduce low end energy that they can't do efficiently.

As far as subs go, that Evolution one you're looking it is, to be brutally honest, absolute pants. It'd definitely be worth your while saving a little more money up and getting something more capable.