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Help me decide the best way to use these amps and speakers!

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REPOSTED FROM THE WRONG SECTION!  (This is a duplicate thread because I posted it in the wrong section and it never got moved to the right one)

Hello good people of Harmony Central, I come to you with an question that needs clarity.  Apologies for the TL/DR post but I want to include all the info I think matters!

I got an outside gig with a country band playing for about 150 people next week.  When I pulled my powered 15s out, one has serious buzz after being stored poorly during the pandemic.  They are old and cheap so it's not worth it to have a pro fix it with a reflow or recap, and I don't have time before the show to do it myself, so I've been looking over my gear for something I can use.  I'm trying not to shell out $ to rent since I have some other gear to try and make it work, just need guidance.

I have two Peavey Impulse 1015's.  They can be bi-amped or full range.  Per the spec sheet, they are rated at 500W RMS full range, or 500W low , 60W high (RMS) if bi amped.  They put out 100 dB at 1W @ 1M full range.

I have two Crest Audio CKS800-2 Amps.  They spec out at 400W RMS per side into 8 ohms, or 1600W bridged.

My understanding is that amplifier RMS rating is best between 160% and 250% of the RMS rating of the speaker, in this case between 800W and 1250W.  So the problem here is that in stereo mode, one amp would push only 80% per side (too low), and two in bridged mode 320% per side (too high). 

Which is likely to be the safer (for the speakers) option while still providing enough sound reinforcement for 150 people, too high or too low?  This is a family-friendly picnic event, not a rock concert, so I'll probably be shooting for around 85-90 dB about 30 feet out from the band where I'll mix from, but of course that depends on how loud the organizers want it and how cooperative the band is.  

I'm guessing that the 400W per side would be just fine with care, but I'd like to get opinions since I've mostly worked with powered speakers in the past.

I also have a Yamaha P2500S amp, spec'd at 250W RMS per side into 8 and a Carvin FET400 at 100W per side into 8.  Should I throw one of these in the mix, like say bi-amp lows at 400W per side with a Crest and the highs at 100W per side with the Carvin?  I have a Furman TX-3 crossover, too.

How would you guys run this configuration with the amps I have? 


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OK so reporting back, the 400W per side amp was not enough, or just barely enough, for the show.  Had to reduce bass guitar and kick levels to prevent clipping at the amp, which was OK, but reduced the quality of the experience.  I didn't have time to make a 4 pole speakon cable to bi-amp with the 400W on lows and 100W on highs, but I'm guessing that would have been just enough to be right for the situation.  Still would have been barely enough I'm guessing, but even without it, it did work out ok (barely).  I would have benefitted from more amp power before clipping for sure!

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