+1 to pretty much what everybody else said here.
I am basing my reply on the specs at the URLs provided below:
Speaker:
Peavey Impulse 1012
http://www.peavey.com/products/index.cfm/item/681/100794/Impulse%201012Woofer: 1208-8SPS specs:
http://assets.peavey.com/literature/specs/116643_13771.pdfAssume 2000 Watt peak, 1000 Watt RMS, but 500 Watt continuous power per AES-2 1984
AMP: Peavey CS8005
Spec Sheet:
http://assets.peavey.com/literature/manuals/80300390.pdfl 420 W RMS into 4 ohms...600 W RMS into 2 ohms (per channel)
l 840 W RMS into 8 ohms... 1200 W F/MS into 4 ohms (bridged)
I am going to assume you are running the three speakers in parallel.
3 8 ohm loads in parallel yields a 2.66 ohm load to the amplifier.
( parallel resistance calculator : ttp://www.sengpielaudio.com/calculator-paralresist.htm )
Question: Should you run the amp in bridged mode?
As stated wisely before in this thread, your amp specs do not quote wattage below a 4 ohm load so I assume bridging is not an option for your configuration. In general bridging is not a good practice anyway, as it increases your maximum voltage output, which increases the risk of thermal damage to your speakers.
(Read: Can I under power my speakers, will clipping hurt them?
http://billfitzmaurice.info/forum/viewtopic.php?f=10&t=1886 )
Question -- are you in danger of burning out your woofers with this amp and those speakers in your configuration?
Assume you are running near 600 Watts RMS into your 2.6 ohm load
600 * 2.6 = 1560. the square root of 1560 = 39.5 volts. This is what your amp should be able to deliver (vRMS)
Each speaker is rated at 500 watts continuous with an 8 ohm resistance.
500 * 8 = 4000, Square root of 4000 is 63.25 vRMS if we leave 3 DB of headroom as a safety this will yield 53.2 vRMS (max)
It appears your amp will not burn out your woofers if they are all wired in parallel to one side of your amp. (tweeters have protection circuit)
If you could bridge into a 2.6 ohm load you would be in great danger of burning out your speakers as your voltage would rise to 55.9 vRMS (calculated with only the 4 ohm rating)
Question: -- Are you under powering your speakers, could your system get louder with more power?
Yes, but not by too much. Ideally you would have one 500 watt (RMS) amp channel feeding each speaker,
With your existing single power amp I would at least wire the outer two speakers into one channel of your amp
and the center speaker into the other channel, feeding the amp the same inputs. You would have to balance the volumes to get an even level across the room.