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Subs and amps

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JohnAyers:
I am getting mixed reviews on if I can run 2 JBL 915S in parallel off of 1 channel using a crown IT4000. My questions would be what, out of the following, would be possible?:

4 JBL 915S with 1 Crown IT4000 (2 subs in parallel on each channel)

4 JBL 915S with 2 Crown IT4000s (2 subs each amp; 1 sub per channel)

Or would I have to use 4 JBL 915S with 4 Crown IT4000s (1 sub each amp; amps in bridge mode)

 

Brian Jojade:
It’s a 4 ohm cabinet. Paralleling 2 on a single channel of an amp is a 2 ohm load.  While you can do that, it’s generally not ideal.  2 amps, each driving one sub per channel would be a good fit.

FYI, the IT4000 amp delivers 2000 watts per channel at 4 ohms, but only 1800 watts at 2 ohms.  In effect, if you put 2 speakers on a single channel, you end up with less power per speaker.

Bridged the amp can deliver 3600 watts at 4 ohms.

The JBL VRX915S is rated at 800 watts RMS, 1600 watts program and 3200 watts peak.

Generally speaking, matching the power rating of the amp with the program rating of the speaker give you the most SAFE output.  If you parallel 2 of the cabinets on a channel, you'd be giving them about 900 watts each.  Totally safe, and would certainly work, but you'd be leaving some headroom on the table.

1 per amp channel is 2000 watts.  Slightly over the program rating, so you need to use some caution and make sure you're not driving them to max output continuously.  For live music, it would be fine. For EDM, you could easily blow the subs.

3600 watts in bridge mode exceeds the peak rating of the speaker.  With that, one good kick hit could damage the speakers, so extreme caution would need to be used to make sure that you don't blow stuff up.

janni locmaren:
I'm going through this question for myself too. I want the d4s amp because it seems like a good option vs paying $800+ for a JL sub for the power I want. Idk

Steve-White:
The best choice of those listed:  4 JBL 915S with 2 Crown IT4000s (2 subs each amp; 1 sub per channel)

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