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Is it safe to run 4 parallel Single Lab12 T60's off each channel of an XTI 4000???

Limiting the LAB12's to 50 Volts equals 350 watts per x4 = 1400 Watts @ 2ohms. The XTI 4000 is rated at 1600W @ 2ohms.

Am I asking for trouble? or should I be ok?

If you run four off each channel, you're running 2.5 ohms on each side. Should be fine (although I wouldn't do it, personally!) Set your limiters, though.

bzb wrote:If you run four off each channel, you're running 2.5 ohms on each side. Should be fine (although I wouldn't do it, personally!) Set your limiters, though.

2.5 oms ???? I thought a nominal 8ohm load x 4 in parellel would give me 2 ohms. The LABS are 6 ohm plus 2 for the cabinet loading giving me 8 ohms total. The Titans are 10 ohms x 4 in parallel would give me a 2.5 ohm load because those drivers are 8ohm plus 2 ohm for cab loading.


Am I wrong?

Also, I was thinking I could limit to 45 Volts if needed to keep things within a safer limit. Any thoughts?

DanielNY wrote:

bzb wrote:If you run four off each channel, you're running 2.5 ohms on each side. Should be fine (although I wouldn't do it, personally!) Set your limiters, though.

2.5 oms ???? I thought a nominal 8ohm load x 4 in parellel would give me 2 ohms. The LABS are 6 ohm plus 2 for the cabinet loading giving me 8 ohms total. The Titans are 10 ohms x 4 in parallel would give me a 2.5 ohm load because those drivers are 8ohm plus 2 ohm for cab loading.


Am I wrong?

Also, I was thinking I could limit to 45 Volts if needed to keep things within a safer limit. Any thoughts?

You're right. I was thinking 3012LF.

Unfortunately, with the XTi series, there's no real way of limiting to a specific voltage. Off the XTi 2000, I run a -6dB limiter on the sub channel and that got me limited to about 55v, IIRC.

bzb wrote:
You're right. I was thinking 3012LF.

Unfortunately, with the XTi series, there's no real way of limiting to a specific voltage. Off the XTi 2000, I run a -6dB limiter on the sub channel and that got me limited to about 55v, IIRC.

I'm not exactly at 4 per channel yet but I'm trying to plan for the future and if need be I can snag an XTI4000 (old Version) now at current low pricing. I wanna keep my rack as light as possible also, so if I don't need another amp to run the 4 per then Im good. Running 4 per channel would only be in a pinch. I can cover almost all of my work with 2 per channel, sometimes 3 per channel, and Just in case (one per year) 4 per channel..and that would be an outdoor event in every case.

DanielNY wrote:

bzb wrote:
You're right. I was thinking 3012LF.

Unfortunately, with the XTi series, there's no real way of limiting to a specific voltage. Off the XTi 2000, I run a -6dB limiter on the sub channel and that got me limited to about 55v, IIRC.

I'm not exactly at 4 per channel yet but I'm trying to plan for the future and if need be I can snag an XTI4000 (old Version) now at current low pricing. I wanna keep my rack as light as possible also, so if I don't need another amp to run the 4 per then Im good. Running 4 per channel would only be in a pinch. I can cover almost all of my work with 2 per channel, sometimes 3 per channel, and Just in case (one per year) 4 per channel..and that would be an outdoor event in every case.

Same sceneario for me. FWIW I have run 8 3012lf loaded titans on an xti4000 for @ 4 hours although not hard, probably 1/2 power and it ran fine BUT I had a spare amp on hand just in case. ;p

netwerks wrote: Same sceneario for me. FWIW I have run 8 3012lf loaded titans on an xti4000 for @ 4 hours although not hard, probably 1/2 power and it ran fine BUT I had a spare amp on hand just in case. ;p

WOW, I just checked out the Peavey IPR 6000, they state these things are designed to be 2 ohm stable. look at these power ratings????? 7lbs and only $650 bucks! I wonder if anyone has had a chance to check these out.

•2,000W RMS x 2 at 4 ohms

•3,000W RMS x 2 at 2 ohms

DanielNY wrote:WOW, I just checked out the Peavey IPR 6000, they state these things are designed to be 2 ohm stable. look at these power ratings????? 7lbs and only $650 bucks! I wonder if anyone has had a chance to check these out.

•2,000W RMS x 2 at 4 ohms

•3,000W RMS x 2 at 2 ohms

I have an IPR1600. It is hard to believe there is actually anything inside, judging from the weight I'd be inclined to believe it's an empty shell only. These things are stupid light.

AntonZ wrote: I have an IPR1600. It is hard to believe there is actually anything inside, judging from the weight I'd be inclined to believe it's an empty shell only. These things are stupid light.

But how do they sound? any comparisons?

The few reviews I managed to find all claim the IPR's clip badly and the power ratings are over stated...

For light and cheap, you can't beat the Crown XLS Drivecore series. 3 year warranty and so far, mine have been great. Running a 1000, 1500, and a 2500.

DanielNY wrote:

AntonZ wrote: I have an IPR1600. It is hard to believe there is actually anything inside, judging from the weight I'd be inclined to believe it's an empty shell only. These things are stupid light.

But how do they sound? any comparisons?

The few reviews I managed to find all claim the IPR's clip badly and the power ratings are over stated...

It sounds fine for my use. It does double duty: light PA use and e-bass backline and does fine for that, but I do not drive it hard so cannot comment on clipping or power ratings.

When testing voltages (for the purpose of setting limiters) it seems the built-in DDT limiter kicks in just before 50V, have not been able to drive mine past 49.4V