I have a 5.1 system with Revel Salons, Studios, and Voice.

The Amp choice comes down to 7500, 7700 Bi-amping the Salons, or 7900.
The Salons are 86 DB at 1 watt.

I mostly listen in the 80 DB range and occassionally in the mid 90's.

I want to never clip. The 7500 might be enough. Although the 7700 bi-amping would assure that I would not ever harm my tweeters. This is my second pair

I would rather not spend the extra for the 7900 but would if there were a quality improvement at the lower levels high 80 DB range.

Does the extra output devices or capacitance tranlsate into better quality sound below 95 DB?

- Rich

To drive those speakers to 95 db you only need 10 watts of power. Any of those amps will provide much more headroom than is required for your listening habits and plenty of extra power if you want to go wild. Bi-amping your tweeters with a 200 watt input (or more if the tweeters are less than 8 ohms)is something you should be wary of if you don't want to toast those tweeters.

True, but peaks can require 9db would require over 200.
There is no problem with have extra power for the tweeters.
They draw very little power in comparison.
Amplifiers deliver the power required by the load so it really does not matter how much extra power is available. Just that the power is clean.

Clipping produces square waves that can damage tweeters. It is much easier to damage speaker with insufficient power than with too much.

- Rich

For a total of 18 db increase you will only need about 70 watts of power. Even less when you consider that the peaks are not a continuous load but are very transient. A quality 200 watt amp would be great for the Revels. Tweeters are usually protected by the crossover circuits from too much power. Depending on how your circuits are wired that crossover could be negated and the tweeters could get as much power as is directed their way by the processor thru the amp. My Maggies tweeters are actually protected by a fuse in case I want to Bi-amp them.

DB To watts (1 one metter)
86: 1
89: 2
92: 4
95: 8
98: 16
101: 32
104: 64
107: 128
110: 256

OK, I see your point. of course, my room is 33 feet long.
I was listening to 103 DB (at 12 feet) today as measured with the Radio Shack meter (fast). I did not hear any clipping.

I guess I was wondering if there was any reason to believe that the 7900 would sound better at non-ear bleeding levels due to its extra output devices, Class-A bias or some such.

- Rich

I don't know about the 7900 but the 7500 will sound much better to your wallet. I am a firm believer that other than controlling speakers amps tend to sound very similar as long as enough headroom is available. Tube amps being the exception when compared to solid state.

I picked up a used 7500 and I am really impressed.
I was toying with getting a 7700 and bi-amping.
Not much cost with B-Stock.

Or, I can just wait for some specials and pick one up if the deal is good enough.
As far as I can tell, other than raw power, no one is claiming better sonic performance with the 7900.

- Rich

Except for power the specs are almost identical. You could still bi-amp by using your old amp for the surrounds.

I sold the Sunfire 7400. Way to many channels left hanging around.

I talked to my brother tonight. He has a Masters in EE.
I did not know he knew that much about amps.

He felt it was entirely possible that the 7900 could have greater control at moderate listening levels. Mainly because the 7900 has 24 output devices will be working half as hard versus the 12 output devices on the 7700 at the same volume.

The feat is getting these devices properly matched and controls to be operating together, which is a testament to modern and amp technology.

Since my Salons dip the 3 ohms they can draw a lot of current in a short time. The transistors have a natural bias so it should be easier for the bigger amp with more output devices to provide that current quickly.

At least that is my non-EE take on what he was telling me.
Basically, he said, If I have the money, given my speakers, the bigger amp should be a benefit.

- Rich