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Powering LS3/5

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I have a pair of LS3/5. I am currently running them with the bass ( base ) units from Kef 105/2. The Ls3/5 still have their crossover as does the Kef 105 woofers. I have the them additionally separated by an older automotive active crossover> I must say, I am really loving it. but I'll bet I haven't even scratched the surface. The LS3/5 are being driven by a Pioneer SA-7700 the woofers are running off a Realistic STA-2000D.
I was reading and discovered that these LS3/5 do well with 35 Watts RMS and apparently EL34s work well with them.

Any advice of clarification on this would be greatly appreciated. I was always under the impression that as nice as tubes can be, they can also be muddy, slow, sluggish. If this is incorrect, how would i go about getting amp the has balanced inputs, no attenuationa or controls are needed. I'd be feeding in direct from a dad with +4 Balanced outs. Hoping to run consistently at 85 db @ 1 meter and occasionally crank it up a bit for 3 or 4 minutes.
 
There are several LS3/5 variations. What is the nominal impedance of your pair?

30+ WPC can be obtained from EL34/6CA7/KT77 bunch, 7591s, and the 6L6GC/7581 group. KT88s will give you more power.

Muddy, slow, and sluggish? Not if correctly handled.

The requisite magnetics ("iron") make tube amps more costly than SS. What sort of budget do you have in mind? Given current realities, Hammond's 1650PA O/P trafo and a variation on The H/K Cit. 5 setup, with 6L6GC O/P tubes, is a reasonable possibility. The Cit. 5 is a superior implementation of what is known as Mullard style circuitry. Mullard style is "idiot resistant" and works well with so/so "iron", like Hammond's.

The 12BY7 used by H/K is getting scarce and is (IMO) best saved for already existing units. I've provided a 6922 cascode that will quite adequately replace the pentode.
 

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