why did you buy a separate HT amp?


i'm in the market for an amp for my 7.1 system (sub is powered). Currently I'm using a Marantz mid-fi AVR. Basically, this receiver cannot power all my speakers to my reference volume. Someone sell me on why i need dedicated power to my 6ohm speakers!
moorefield
I added an external amp to my receiver and it got a new lease on life. I'm still using a ProLogic "dolby-digital ready" receiver as my main unit (Sony GA7-ES). As such, it does not have equal power to all five channels, which was normal for the ProLogic specs in those days. It has beefy parallel push-pull amps for the front three channels (90W RMS) but fairly pedestrian (non-high current) 40W power for the rears.

Sony thoughtfully provided a "power swap" feature on the 7ES which when engaged, routes power from the main 90W amps to the surrounds and lets you add a 3-channel external amp to drive the fronts. I chose an Arcam Alpha 10p x 3 channel amp at 100W and now have matching power to all three front speakers with the Sony just idling on the rears. I bought the Arcam amp used on Audiogon for a fair price and it's really made a difference in my system. And I can still use it if I move beyond the 7ES to a newer receiver or processor. -jz
Yup if you add a beefy 2 channle amp from any number of makers your AV unit should be ok for center and surrounds. While I dont have a reciever I do run a hunble 6 channel Rotel which can be bridged up to 3 channels so I bridge the center only and use stock power for all surrounds. I get 120W to center and 60 to all 4 surrounds BUT I only roll them off at 80Hz, if you intend to run more full range speakers that isnt likely to be enough power but for me in my 14X25 HT I have never felt I need more power, my surrounds are 92db efficient if I recall. I do listen loud and have a picky personality but again for HT its fine for me.............music is another animal.
good response guys...i should have explained my question a bit better. I am considering a sep. amp verses a newer 'higher power' AVR. I have HD DVD player and want the newer audio formats decoded.

I may go with the suggested 3 channel amp route and add on as funds dictate.

thanks again,
Greg
It's not just a power issue, it's a noise floor issue. I don't like the hashy sonic mess and compression you get when you have low-level analog and digital decoding components sharing a chassis with all the vibration (60 Hz) and heat you get with what should be a high current 7-channel amp.

I have my power amps on a separate shelf from my pre/pro. True, you can get 150-to-190 wpc A/V receivers, but not only are you adding all that jazz to a low signal chassis, in most cases they compromise the power supply to get everything to fit. And that's another source of compression you get with a receiver.

Look at the specs and test reports for most A/V receivers. They rate the power with one channel driven, and often with a 1KHz test tone (no bandwidth) at 1% distortion. An A/V receiver tested at 90 wpc under those circumstances only puts out about 43 wpc with all channels driven, 20-20KHz, at 0.1% distortion. And I've seen enough Home Theater mag test reports to prove it.

Most A/V receivers rated at 125 wpc will not have anywhere near the balls of a similarly rated separate amp from Adcom, Outlaw, or Parasound, never mind the high-priced spread.
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I'm with Pacific Island Audio. I use a separate 300wpc amp for my front speakers, along with a passive pre-amp with pass-through. Maximized two channel, not as much strain on my multi-channel amp. Enables bi-amping of center channel with the open channels on the surround amp.

Enjoy,

Dan
Have you considered separate amps for only the front channels and let the AVR handle the surrounds? Since the surround channels rarely get driven hard, it would be a more economical solution. You could even get away with the AVR handling the center. With it driving only 3 channels it should be able to put out the volume you want. This will make your setup better for music too.