if you use one channel for the sub, and the other channel for the two mains, then you are feeding the two mains with only one channel, hence not stereo. You need three channels for that (assuming you have passive crossovers).
If you go with active three way towers, and a sub you need in total seven channels of amplification! one channel for each driver in each of the towers, + the sub!
Tony.
If you go with active three way towers, and a sub you need in total seven channels of amplification! one channel for each driver in each of the towers, + the sub!
Tony.
I would suggest 2-way mains if you're going to have an active sub system anyways. Which would basically make the total system a 3-way anyways.
Assuming a 7.1 system, I would suggest 4 or 5 or 8 stereo amplifiers depending on how you want to deal with your crossovers.
With 4 stereo amps: Use each of 3 of those amps as the various R/L main stereo pairs, then use the final, which should be a more powerful unit, for the center and sub/s (center on 1 channel, sub/s on the other). This will require passive crossovers and passive padding.
With 5 stereo amps, again use the first 3 as the various stereo pairs, then a dedicated amp is used for the center channel, with the option to do an active crossover on the center channel only, and the final amp dedicated to the sub/s (either bridged mono or driving a stereo pair of subs).
With 8 stereo amps, each of the first 7 amplifiers is dedicated to a single 2-way speaker. An active crossover (which is actually built into those crown amps, so you don't need to buy any separate hardware) is used to split the highs and lows across the 2 channels of each amp for each final channel of the system. The final 8th amp, is for the sub, again, it can be bridged or operated as a stereo pair depending on the design goals of the system.
You'll want to have a central processing unit to handle the decoding, D/A conversions and pre-amp stage. I'm not familiar with this sort of gear but am sure such a pre-amp unit exists. I'd suggest getting something that can take care of of crossing over all the deep bass from the mains/center/surrounds and mixing it into a line level signal either stereo or mono right in the unit. This will cut down on a LOT of external wiring and mixing needs.
For the speakers. I'd build the mains based around these woofers: RCF L8S800 8" Midbass Speaker 294-828
The front 3 "main" channels I would probably do 2 or more woofers per channel. The other 4 surround speakers I would just build compact units with 1 woofer per unit. I know some might balk at the suggestion, but I'd be tempted to use a compression horn for the front mains in order to keep up with the multiple woofers (something like: B&C DE250-8 1" Polyimide Horn Driver 8 Ohm 2/3-Bolt 294-605), but then, on the surrounds, with the single woofer, I'd use these: Morel CAT 378 1-1/8" Soft Dome Horn Tweeter 277-084 (horn loaded domes should match the sensitivity of the RCF woofers well). In the case of the system with the active crossover for all 7 main channels, and 8 stereo amps, you can use the level adjust for each channel on those pro amps in order to fine tune the high and lows for each channel. The single woofer boxes with the morel dome will probably sound fine with each channel of the bi-amp set with equal gain, however, on the front mains, you'll need to knock off a lot of the gain on the highs to match it up since those compression horns are so remarkably efficient. Otherwise, on the 4-5 amp builds, you'll be building passive crossovers for the mains, and you'll have to plan on impedance correction filters for the high and low drivers, as well as some significant padding on the horn driver.
Whether you go active or passive on the x-over, I'd shoot for ~1800hz or even slightly lower x-over point to keep those 8" drivers from getting bright spots.
These: Crown XLS 1000 DriveCore Series Power Amplifier Flexible for Any Pro Audio Amplification Need 245-500 <should be more than enough for any channel in the system. However, it wouldn't be a bad idea to size up the the center, sub, and front mains a bit. The XTi series has more flexible x-over options, however, I think for the $200+ premium per unit, you could actually be better off simply using a separate multi-channel x-over. Assuming a bi-amped setup, I think I'd be tempted to run with 3x XLS1500s for the front 3 "mains,", 4x XLS1000s for the surrounds, and maybe a XLS2000 or 2500 for the sub/s, maybe a pair of them for the subs if you really want to get nuts and have a lot of bottom end hurtin power.
I understand you already have a pretty beefy sub available there. So just try that by itself on the big amp and see if it is enough for the room characteristics. Those TC style units do seem to get some pretty nice praise for sounding good, however, if you decide to go another route with your bottom end, 2-4 21" RCF or B&C drivers would probably be the direction I'd take.
Eric
Assuming a 7.1 system, I would suggest 4 or 5 or 8 stereo amplifiers depending on how you want to deal with your crossovers.
With 4 stereo amps: Use each of 3 of those amps as the various R/L main stereo pairs, then use the final, which should be a more powerful unit, for the center and sub/s (center on 1 channel, sub/s on the other). This will require passive crossovers and passive padding.
With 5 stereo amps, again use the first 3 as the various stereo pairs, then a dedicated amp is used for the center channel, with the option to do an active crossover on the center channel only, and the final amp dedicated to the sub/s (either bridged mono or driving a stereo pair of subs).
With 8 stereo amps, each of the first 7 amplifiers is dedicated to a single 2-way speaker. An active crossover (which is actually built into those crown amps, so you don't need to buy any separate hardware) is used to split the highs and lows across the 2 channels of each amp for each final channel of the system. The final 8th amp, is for the sub, again, it can be bridged or operated as a stereo pair depending on the design goals of the system.
You'll want to have a central processing unit to handle the decoding, D/A conversions and pre-amp stage. I'm not familiar with this sort of gear but am sure such a pre-amp unit exists. I'd suggest getting something that can take care of of crossing over all the deep bass from the mains/center/surrounds and mixing it into a line level signal either stereo or mono right in the unit. This will cut down on a LOT of external wiring and mixing needs.
For the speakers. I'd build the mains based around these woofers: RCF L8S800 8" Midbass Speaker 294-828
The front 3 "main" channels I would probably do 2 or more woofers per channel. The other 4 surround speakers I would just build compact units with 1 woofer per unit. I know some might balk at the suggestion, but I'd be tempted to use a compression horn for the front mains in order to keep up with the multiple woofers (something like: B&C DE250-8 1" Polyimide Horn Driver 8 Ohm 2/3-Bolt 294-605), but then, on the surrounds, with the single woofer, I'd use these: Morel CAT 378 1-1/8" Soft Dome Horn Tweeter 277-084 (horn loaded domes should match the sensitivity of the RCF woofers well). In the case of the system with the active crossover for all 7 main channels, and 8 stereo amps, you can use the level adjust for each channel on those pro amps in order to fine tune the high and lows for each channel. The single woofer boxes with the morel dome will probably sound fine with each channel of the bi-amp set with equal gain, however, on the front mains, you'll need to knock off a lot of the gain on the highs to match it up since those compression horns are so remarkably efficient. Otherwise, on the 4-5 amp builds, you'll be building passive crossovers for the mains, and you'll have to plan on impedance correction filters for the high and low drivers, as well as some significant padding on the horn driver.
Whether you go active or passive on the x-over, I'd shoot for ~1800hz or even slightly lower x-over point to keep those 8" drivers from getting bright spots.
These: Crown XLS 1000 DriveCore Series Power Amplifier Flexible for Any Pro Audio Amplification Need 245-500 <should be more than enough for any channel in the system. However, it wouldn't be a bad idea to size up the the center, sub, and front mains a bit. The XTi series has more flexible x-over options, however, I think for the $200+ premium per unit, you could actually be better off simply using a separate multi-channel x-over. Assuming a bi-amped setup, I think I'd be tempted to run with 3x XLS1500s for the front 3 "mains,", 4x XLS1000s for the surrounds, and maybe a XLS2000 or 2500 for the sub/s, maybe a pair of them for the subs if you really want to get nuts and have a lot of bottom end hurtin power.
I understand you already have a pretty beefy sub available there. So just try that by itself on the big amp and see if it is enough for the room characteristics. Those TC style units do seem to get some pretty nice praise for sounding good, however, if you decide to go another route with your bottom end, 2-4 21" RCF or B&C drivers would probably be the direction I'd take.
Eric
Congrats on recognizing the value of "band" equipment.
Crown has a few different product lines and the ones you show are only rated to 4ohms. As the owner of some of the hungriest speakers known, if the amp's rated at 4ohms that's what you can count on.
When it comes to amplifiers it's not the watts that matter, it's ohms. The more "linear" an amp, the better. Ideally (Mark Levinson,) an amp would double in wattage for each half in ohms. 800wpc @ 8, 1600wpc @ 4, 3200wpc @ 2. The closer the amp comes to doubling, the more "linear" it is.
The other two lesser shown specs are "rise time" and "head room." The faster the "rise time" the quicker an amp can respond to signal demand. "Head room" refers to how much "extra" an amp has in reserve to respond to signal demand (and this is in db. 3db = double. 6db = quadruple.)
Running an amp at 2ohms on one channel and 8ohms on the other is a waste since it would need to be a 2ohm amp. Better to bridge or get a mono amplifier.
If this is going to be a "stereo + sub," biamping the "stereo" will just introduce confusion. If you are going for surround + center, don't go cheap on the center. Most surround has a large portion of the "front" in the center channel.
"Damping factor" is often shown and is meaningless if it's over 100.
Note: the Peavey deliberately does not show THD info. At 7 LBS and 700wpc, it could be disappointing. (I have Peavey stuff that I am happy with.)
You may also want to look at QSC (I am not affiliated.)
P
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