Amp advice for sub drivers? - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 11th January 2012, 10:06 PM   #1
sploo is offline sploo  United Kingdom
diyAudio Member
 
Join Date: Mar 2007
Default Amp advice for sub drivers?

[This may be better in the Amplifiers section, but it is specifically about sub drivers, so I'm hoping to find the bass freaks here]

I have a set of four Peerless XLS10 P830452 drivers (4Ohm version) that I've had kicking round for a few years. A pair of them have been sitting in a ~40 litre (1.4 cubic ft) box, wired in series to create an 8Ohm load and powered by an Alesis RA500 amp (in bridged mode). The RA500 has been fed with the SUB output from my AV receiver.

The RA500 is rated at 500w RMS into 8Ohm when bridged, and I've been more than happy with the output. Not earth shattering, but a nice bit of extra bass for movies.

I've been given approval from she-who-must-be-obeyed to build some new enclosures to make use of the extra drivers. My plan would be to make two boxes, each with two drivers, and place them near the front speakers (I can't fit another configuration in the room, so can't do four single driver subs).

The obvious solution was to get another Alesis RA500, but they're discontinued. I've looked at the Behringer A500 but it's mismatched in 'only' giving 375w RMS into 8Ohm when bridged.

I could make use of the RA500 elsewhere, so is there a better solution? Perhaps a single amp that would provide 2x500w into 8Ohm loads, or even pair of decent sub plate amps?

I've spotted the Behringer EUROPOWER EPQ1200, which claims 2x320w into 8Ohm, the EUROPOWER EPQ2000 claims 2x600w. Any other/better suggestions?
  Reply With Quote
Old 11th January 2012, 10:58 PM   #2
diyAudio Member
 
revboden's Avatar
 
Join Date: Feb 2011
You could just wire up the new boxes series-parallel to keep the overall load at 8ohm, with the extra sensitivity you should get ~6db more output.

How big will the new boxes be? I'm assuming sealed.
  Reply With Quote
Old 12th January 2012, 08:59 AM   #3
sploo is offline sploo  United Kingdom
diyAudio Member
 
Join Date: Mar 2007
Quote:
Originally Posted by revboden View Post
You could just wire up the new boxes series-parallel to keep the overall load at 8ohm, with the extra sensitivity you should get ~6db more output.
This is where my electrical knowledge falls down... surely that would be generating extra output from nothing? I.e. I can't change the wiring to get more output - only to create a load with a safe resistance level for the amp?

Actually... can you even get an 8Ohm load with four 4Ohm drivers anyway?

4+4 in series = 8Ohm
4+4 in parallel = 2Ohm

Take two of the the 4+4 in series (8Ohm) and wire them in parallel -> 4Ohm.
Take two of the the 4+4 in parallel (2Ohm) and wire them in series -> 4Ohm.


Quote:
Originally Posted by revboden View Post
How big will the new boxes be? I'm assuming sealed.
Probably around the 40 litre mark, and yes, sealed. I did look at various ported/vented options, but the size increases greatly (XLS10 isn't well suited to ports) and I'd need some filtering at the low end to prevent driver damage.

Ideally, the best configuration of the XLS10 seems to be with its sister unit, the XLS10P passive radiator. Even Peerless' own docs explore sealed/ported/passive rad and advise passive radiator.

All the more dumb that the radiator is no longer available, but you can still buy the driver!
  Reply With Quote
Old 12th January 2012, 10:07 PM   #4
diyAudio Member
 
revboden's Avatar
 
Join Date: Feb 2011
Sorry, I saw the 8ohm bit at the top and misspoke. You are correct, series-parallel would give you 4Ohms.
  Reply With Quote
Old 15th January 2012, 03:00 AM   #5
mdocod is offline mdocod  United States
diyAudio Member
 
Join Date: Dec 2011
Location: Black Forest, CO
Send a message via AIM to mdocod
How about a Crown XLS 1500 or 2000 Drivecore series? They can do 2Ohm/channel or 4Ohm bridged so, matches your loads well, and 2100W for the XLS2000 would probably be pretty good... Might be a good idea to do some research though and see if these ratings are realistic

Eric

Last edited by mdocod; 15th January 2012 at 03:09 AM.
  Reply With Quote
Old 15th January 2012, 08:41 AM   #6
diyAudio Member
 
pheonix358's Avatar
 
Join Date: Jul 2008
Location: Stockport South Australia
Parallel the new set with the originals and you will get a 4 Ohm load. If your amp can handle that it should deliver more current = more power. You will get a 6dB increase, +3 for doubling the cone area and +3 for halving the impedance. (This assumes your amp can run into 4 Ohms)
__________________
What we don't understand is called magic.
  Reply With Quote
Old 15th January 2012, 08:51 AM   #7
diyAudio Moderator
 
pinkmouse's Avatar
 
Join Date: Apr 2002
Location: Chatham, England
Call it bias if you'd like, but coming from the pro audio world, I wouldn't touch a Behringer power amp with a bargepole.

Have a look at the Yamaha PS range. Good price, sound and stunningly reliable, (but Yamaha do have great after sales service if you need it, I'm not sure the same can be said for Behringer ).
__________________
Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
  Reply With Quote
Old 15th January 2012, 09:32 AM   #8
ODougbo is offline ODougbo  United States
diyAudio Member
 
Join Date: Aug 2011
Location: Maryland USA
You really only need 2 XLS10 drivers, I will be glad to take the extra pair off your hands.

Here's a thought, how far away are the amp(s) going to be from the subs? I ran 3meters once, with super thick wire and the box just "knocked". The advantage with a plate is the amp is right next to the driver, so no wire loss problems. That said I don't use them (plate amps), but keep the power amp(s) close to the subs as possible.

Parts Express has several "levels" of PRs to look at; I'm sure PE would help you find a match, if you go back to that idea.

It is always good to hear about a sensible woman!

Last edited by ODougbo; 15th January 2012 at 09:47 AM.
  Reply With Quote
Old 15th January 2012, 12:05 PM   #9
diyAudio Member
 
chris661's Avatar
 
Join Date: Feb 2008
Location: Sheffield
Blog Entries: 8
ODougbo, I'm not sure if you're aware of the heavy import costs for us here in the UK, but the charges would almost certainly rule out the PRs.

sploo, I've been using a Samson servo amplifier for my subwoofers - one of their higher power ones ought to do nicely. They appear on eBay quite often, and have found they're suitably specc'd for Pro audio use: paralleled 15A output devices, lots of heatsinking (even the rectifier is bolted to a chunk of aluminium), and a decent power supply.
I use one rated for 120w/ch at 4ohms (though it has enough voltage swing to do 300w per side - don't think the PSU would be happy though), and have never had trouble filling large rooms with my inefficient subwoofers.

Chris
  Reply With Quote
Old 15th January 2012, 06:34 PM   #10
diyAudio Member
 
revboden's Avatar
 
Join Date: Feb 2011
Quote:
Originally Posted by pinkmouse View Post
Call it bias if you'd like, but coming from the pro audio world, I wouldn't touch a Behringer power amp with a bargepole.

Have a look at the Yamaha PS range. Good price, sound and stunningly reliable, (but Yamaha do have great after sales service if you need it, I'm not sure the same can be said for Behringer ).
+1

The Yamaha P3500S would do nicely.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Need advice - Desk with built in 3" drivers & amp lersince1991 Parts 11 6th August 2010 02:01 PM
need advice about Monacor drivers steph_tsf Multi-Way 10 24th May 2010 11:17 PM
Your advice on some new (outdated) drivers retroman Multi-Way 5 23rd May 2009 09:20 AM
Need Advice for Choosing Fostex Drivers ezkcdude Full Range 5 12th November 2007 01:01 PM
MCM drivers--need advice Switch Multi-Way 2 25th November 2006 07:01 AM


New To Site? Need Help?

All times are GMT. The time now is 06:49 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2