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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Travis Dean on May 28, 2017, 01:16:49 pm

Title: LabSub Cluster dB
Post by: Travis Dean on May 28, 2017, 01:16:49 pm
Just wondering if someone could possibly give me a guesstimate for the output on a cluster of 4 LabSubs.  I currently using a Crown XLS5000 to run all four subs.  It sounds pretty good but I know I'm not getting the maximum output for these subs.  If I only hooked 2 subs up in stereo instead of the four, would I get more dB's or close to the same since I know 4 subs in a cluster adds about 6 more dB. Also, I am using a dedicated 20amp generator, 120v.
Here are the specs for the xls5000 amp:
8-ohm Stereo (per channel)
1 kHz
Continuous Average
Power with 0.1% THD
1,100W
1,800W
2,500W*
3,600W
8-ohm Bridge-Mono
2-ohm Stereo (per channel)
4-ohm Stereo (per channel)
XLS 5000
*with 1% THD.
4-ohm Bridge-Mono
5,000W*
Title: Re: LabSub Cluster dB
Post by: Tim Weaver on May 28, 2017, 01:27:21 pm
You want to use them all 4 together if possible. They will be more efficient at lower frequencies this way.

What you need is a different amp. I've never used the XLS5000 and been happy with it. Get a 4 pack of RMS1850HD's maybe? Or if you can an Itech x000. It will make a noticeable difference in your output.
Title: Re: LabSub Cluster dB
Post by: John Chiara on May 28, 2017, 02:24:09 pm
You want to use them all 4 together if possible. They will be more efficient at lower frequencies this way.

What you need is a different amp. I've never used the XLS5000 and been happy with it. Get a 4 pack of RMS1850HD's maybe? Or if you can an Itech x000. It will make a noticeable difference in your output.

I have found the old PL 9.0 to be a perfect match for 4 Lab subs.
Title: Re: LabSub Cluster dB
Post by: Travis Dean on May 29, 2017, 12:27:31 am
You want to use them all 4 together if possible. They will be more efficient at lower frequencies this way.

What you need is a different amp. I've never used the XLS5000 and been happy with it. Get a 4 pack of RMS1850HD's maybe? Or if you can an Itech x000. It will make a noticeable difference in your output.

Thanks, kinda what i figured. 
I only play 2 or 3 outdoor venues a year so not looking for other purchases.
Title: Re: LabSub Cluster dB
Post by: Mark Wilkinson on May 29, 2017, 10:39:41 am
To see what's the most you can get with what you have,
I would put all four boxes in series-parallel so they equal the load of one box,
and then put that across the amp in bridge mono.

edit: pls nevermind, no advantage gained using above recommendation
I looked at amps specs again and see there is no difference, either in power or load per channel,
in just paralleling two boxes across each channel
Title: Re: LabSub Cluster dB
Post by: Art Welter on July 16, 2017, 04:31:26 pm
Thanks, kinda what i figured. 
I only play 2 or 3 outdoor venues a year so not looking for other purchases.
Travis,

The LabSub impedance drops to only 2.2 ohms at Fc and a few other frequencies, with a pair per side in parallel the amp would see as little as 1.1 ohms and may current limit well below full power. It may actually put out more power with a pair in series per side.

Art