What to do with my Adcom 555 II

[RaT]

I have a question regarding the advisability of incorporating a Adcom amplifier (555 II) to run my front mains, I have the amplifier left from years ago. Question is, could I use a AVR like a Denon 3805 to do all the processing and preamp work and center/surround work while letting the 555 II handle the mains. Is this configurable? Does it even make sense? The Adcom has been used very little but I know it has a reasonable amount of power at 200 watts/channel. With a load like the Paradigm Studio 100's, I thought it might give a AVR like the Denon 3805 a break.

 

[WmAx]

Sounds like a fine idea to me. But do you really need the additional power from the Adcom? Doesn' the reciever power the speakers fine by itself? I don't know if the Adcom 555 II shares teh same conservative rating as the original Adcom 555 -- but the original was measured by independant reviwers to have higher power output than rated. From my memory, one reviwer measured about 250 per channel @ 8 ohms and another's unit was around 230 watts @ 8 ohms. I think one of the measurements was from Stereophile.

-Chris

I have a question regarding the advisability of incorporating a Adcom amplifier (555 II) to run my front mains, I have the amplifier left from years ago. Question is, could I use a AVR like a Denon 3805 to do all the processing and preamp work and center/surround work while letting the 555 II handle the mains. Is this configurable? Does it even make sense? The Adcom has been used very little but I know it has a reasonable amount of power at 200 watts/channel. With a load like the Paradigm Studio 100's, I thought it might give a AVR like the Denon 3805 a break.

 

[Colonel_Tomb]

I have a question regarding the advisability of incorporating a Adcom amplifier (555 II) to run my front mains, I have the amplifier left from years ago. Question is, could I use a AVR like a Denon 3805 to do all the processing and preamp work and center/surround work while letting the 555 II handle the mains. Is this configurable? Does it even make sense?

Hmmmm . . . I owned a GFA-555 for 13 years, and I once thought about doing the same thing. Because A/V preamps are soooo expensive, I once considered replacing my stereo preamp with a Denon AV receiver, but, since I didn't want to depart with the mighty Adcom, I figured I'd use it to drive my mains. In the long run, though, I decided this was a needlessly complicated arrangement, and I eventually upgraded to five-channel separates.

I don't see any technical problem with what you're suggesting, though, and it might benefit straight two-channel music simply because the Adcom has enormous power reserves. On the other hand, I'm not a believer in significant sound-quailty differences between well-designed amps, so, as long as you keep the Denon within its power limitations, there'd probably be no difference at all.

 

[Unregistered]

I have the AVR3805 and the original Adcom GFA-555. I use the Adcom to power the front mains. Without doing an A/B comparison, I cannot say I hear a difference in sound quality.

 

[warnerwh]

Movies sometimes draw alot of power and the Adcom will give you extra headroom. If you listen at low levels it probably isn't a problem but if you turn it up much at all it would be good to have the extra headroom. Explosions etc. can draw alot of current. Then again I'm biased toward having high power to ensure clipping won't happen and most people seem to get by with 100wpc. Also it would make it easier for the power supply in your receiver to drive only the center and surrounds.

 

[RaT]

That is precisely why I would like to do it. Having the extra headroom. There is no question that when it comes to power, the mains are the speakers I want to have it. While I agree I would not hear any differences in the quality, it's having the extra power and most importantly the huge reserve the 555 (damping factor > 800) has over most any if not all AVR's. I must admit to turning up my sound level at times with various music only sources. There are times that even my old pair of KEF 103's will put the 555 into clipping as the 555 so readily shows with its yellow and then red LED's, they like the Paradigms do enjoy the wattage fed them. I was not sure an amp like the Denon 3805 even had pre outs to accomodate external amplifiers since I have yet to purchase a AVR. I'm currently using a old Lexicon surround processor/preamp with a Yamaha AC3 processor.

PS. the primary difference between the Adcom 555, the 555 Pro and the 555 II was simply the level of distortion. The power level was always a very conservative 200W/325W/600W in a 8ohm/4ohm/8 ohm bridged setup. How valid the argument was that it could drive highly reactive loads well below even 2 ohms was sort of it's claim to fame.

 

[Unregistered]

RaT, the 3805 has pre-outs, and I am using them with my GFA-555. It works great, I had the 555 driving my Energy Veritas at reference level. It never clipped!