Which Amp for uppermost freq' in tri-amped setup?


I need to choose an amp for the upper frequency range in
my tri-amped system, and I may be making this decision more
complex than I need to. Crossover frequencies will be 150Hz
and about 4000Hz. I have two Marchand crossovers (XM-9),
two NAD 2600a amps for the woofers, and a Linn 5105 amp
for the mids. (I may only use one of the NAD's, but could
run two in mono if desired.) So,the amp requirements for
the top end should be easy to satisfy, no? High wattage
or current flow should not be necessary. I would think
low distortion up to, say, 50KHz should be a more important spec.
I'm leaning toward a Linn LK85. I know this is an
unusual question; I sincerely welcome your suggestions and
comments.
rbj
I've owned the Bedini and the Pass - the Pass is better but either is a good choice.
Compound's can work out nicely if done carefully. My only concern is with the lower impedance. I think that the NAD would get "mushier" as the load drops. Then again, having two amps with four channels to hit the four drivers would mean that none of them would see anything less than 8 ohms, so that might be a valid approach. That is pretty similar to what i did ( multiple channels to drive multiple drivers ) in one system.

With all of that in mind, give it a go with what you currently have. You have all the gear necessary to actively tri-amp right now. You can play around with what amp runs what frequency range, where your crossover points work best, etc... Once you get things dialed in, you can enjoy until you can afford to move forward with your next amplifier upgrade. Then again, if you get it working and you're happy with the results, you might also save yourself a LOT of time and money. It's worth a try : ) Sean
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Thank you gents very much. I haven't bought anything yet,
still wondering. Sean, your suggestion to sell the NADs
is something I almost did once & still might. I'm building
speakers too, they are not done either. I'm building a
compound/isobaric woofer section (dual 8-ohm drivers),and
thought 2 mono NADs would be a way to start, that is,
without selling my car to buy parts.
Sounds like you've got your hands full. I wish you the best in your project and hope you can make it work to your satisfaction. Active multi-amping can be tough to dial in, but it can sound SOOOO nice : )

I ran a 2600 for a while with a set of Klipsch Heresy's. The "warm and smooth" NAD sound complimented the "hot" sound of the horns pretty well. While the 2600 is not a bad amp, it is not "commanding" enough on bottom end. I would sell both of those ( i see that the used prices on these have climbed up somewhat, making it a good time to unload them ) and look for either an Electron Kinetics Eagle, Perreaux PMF-3150, Robertson 6010, Aragon 4004, etc... These are all excellent "bang for the buck" amps when it comes to low frequency reproduction and impact. You might be able to find better amps for bottom end, but you'll be paying a LOT more for it too.

For top end, look for a Forte' 4 / 4A. Class A bias, 50 @ 8, 100 @ 4, etc... and sounds very sweet, airy and delicate. Trounces amps costing WAY more money with much bigger names.

Take these suggestions for what they are worth. That is, slightly less than what you paid for the advice : ) Sean
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If you get an LK 85, use that on the mids and use the 5105 for the tweeters, sounds backwards, but Linn is fanatical about using the best amp on the tweeters. The 5105's a great amp, have you given any thought to buying another one of those?? Or two and selling the NAD's? You might find it easier to set up and use with all matching amps.

Just my .02, I run 6 of the 5105's in my system, hell I even have a spare one I was going to sell, but decided to keep in case one of the other ones fail. These should start to show up used more frequently now that they are discontinued.
There was a Spectral DMA 50 offered here the other day for a reasonable price. I find it an ideal amp for the high end of the musical spectrum. It does not necessarily have to be run with MIT wires. Just an idea. Cheers,