Hclarkx

I had a strange experience with the RC-7. My RC-7 replaced an RC-3. With the RC-3 my room frequency response before correction (by an Audyssey EQ) was moderately flat from 50 to 150 Hz. There was about a 5 db broad "hump" around 100 Hz that the Audyssey equipment easily flattened. However, with the RC-7, installed in exactly the same location, with no other room changes, that broad "hump" went over 10 db. The Audyssey EQ helped a lot, though didn't fully correct it. I know this hump is a room mode issue, but I'm at a loss as to why the RC-7 excited it to a much larger extent than did the RC-3. I have to wonder if the RC-7 doesn't have its own peak in that area that just happened to aggravate the room mode. I think the RC-7 and RC-3 are 3-way speakers (or you might call them 2.5 way) where the second woofer cuts in only at the low end to extend the bass response. Maybe there's an issue with the second woofer crossover in mine. Anyway, this is my only issue with the RC-7. Other than this, I'm very happy with it as I was with the RC-3.

J, I think you've got it handled well. My experience with Class D was very early and not a good one. I moved away from Class D before getting my RF-7's. At first I thought the RF-7's were crap ... way to harsh. Then I figured out they were just revealing issues with my CD player. That suggested the RF-7's wouldn't work well with a Class D, but, from your points, it's clear Class D has come a long way and are up to the RF-7's. I think the 7's reputation of being harsh is just them revealing inferior equipment upstream. I did have an Adcom 5803 for a couple of years and was running it when I got the RF-7's. It didn't take long to figure out the 5803 had far more power than I needed for the RF-7's. Moreover it ran very hot even at idle as most FET amps do. That heat made arranging and protecting my precious equipment difficult. I think it was when I got the Audyssey Sound EQ Pro that I really understood how little drive the RF-7's required since it tells you clearly the relative drive each speaker needs in db. I should qualify my observations though. I only drive my RF-7's down to an 80 Hz crossover to my subs. I assume everybody does that and maybe that's not a safe assumption. Crossing over at 80 Hz reduces the power the RF-7's need. If one is driving them full-range, then power will be more of an issue. Fish, were you driving the 7's full range when you saw clipping lights on the 5802? I never did with the 5803 and would get them fairly loud in a 1400 square foot room (when my wife was out). I also found I needed four 15" subs to keep up with the RF-7's and get flat response down to 20 Hz and below. This is done with an Audyssey Sub EQ and four large sealed subs and using four channels of an Adcom GFA-7500.

Whoa, think about this a minute. The RF-7's have a sensitivity of 102 db!! Hence they require six times less power than a typical speaker set with 93 db sensitivity for the same SPL. The RF-7's 250W power rating (1000W peak) is impressive but will never happen in practice with a 102 db speaker. I've driven mine with as little as 50W per and could drive them as loud as I dared with no loss of quality. You don't need a class AB amp of more than about 100W rating for the RF-7's to remain in the class A (highly linear) region virtually all of the time. Even at Xmax they won't be much out of the Class A region of a 100W AB amp. Hence I would worry more about the quality of the amp than the power rating since the RF-7's will reveal any imperfections in the amp or elsewhere in your system (including a less than high quality D/A in your CD player .... or receiver depending on where you convert your CD digital signal). Unless your home theater is in a large barn, 100W will be enough. And 100W may be more than you need there. Some tube fans drive these with 20 and 30 Watt tube amps. You will want high-end amps especially if you go class D since the RF-7's will reveal any digital artifacts that make it to the output. That will come across as harshness, and sound much like a low-end CD D/A computer.