Seperate amp for passive subwoofer

[admin_exported]

Howdy all,

I've got a passive sub (ie. a sub without amp) that I want to use again, but with an amp, the amp (not bought yet) will most likely not have a passive sub out so i'm wondering if a seperate "sub only" amp could be bought? or would it be a case of finding an old amp off a active sub system?

Cheers chaps,

Ben

 

[Big Chris]

TBH Ben. Once you look into buying a power amp and a crossover for your sub, you could probably buy a good active sub. Maybe it's something to look into, unless this passive sub is a stellar performer.

 

[up the music]

There's a fair range of DIY sub plate amps available. They are often designed to drop into a cutout in your sub cabinet but can be housed in a seperate box. They are the same as the amp section you get on most active subs and have all the controls you'll need built in.

Alternatively something like a Behringer DCX2496 or Velodyne SMS1 can be fed a pre out signal and do your crossover/phase etc. Basically these act as signal processors. Then pass their outputs to your normal power amp and a seperate power amp for the sub and you're away.

Plate amps start at under £100 but you could easily top £1000 for an SMS1 plus beefy amp. Try to get a handle on how good your drive unit is and whether it's worth spending money on.

Do a Google for 'sub plate amps' and nose around some of the DIY/HomeBrew audio forums to get an idea of what you want.

 

[Anonymous]

The DCX2496 can let you do lots of adjustments for your sub, before passing onto a power amp.

In the above suggestion, I am not sure why the normal amp would comeback into the chain after initally supplying the pre-out signal. Would it not be: -

Normal Amp to main speakers

+

Normal Amp's pre-out to DCX2496 to Poweramp to sub

The suggestion of looking into active subs are reasonable. BK do some good ones starting from £200. The DCX2496 will set you back by a couple of hundred, plus you need to find a power amp.

I don't know much about plate amps.

 

[up the music]

The processor SMS1 or DCX2496 needn't be used to filter the low frequencies from the main system as you say. In fact, I run my main speakers unfiltered and dial the subs in to augment them.

It's likely to be easier to filter the main speakers low end and not have to worry about matching the sub high frequency roll off with the main speakers bottom end rolling in slopes. Filtering the mains does mean letting the subs run to higher frequencies where they might start to become directional with small main speakers.

From what I've read there seems to other pros and cons to each method, though tbh I can't remeber them all.

I've not heard one but the way their users rave, I'd second that vote for BK subs. I've heard comments of the DCX2496 sounding like PA, though there seem to be mods to turn it into a stellar performer. As TNTTNT said it's also very versatile. It can bu used as a DAC and active stereo 3 way crossover in one box for example.