Wrat, what is a 275 mk6? You're making me nervous!
A Mcintosh (or any decent) tube amp will deliver a PERFECTLY ACCURATE, "clean and tight" bass frequency signal to current model ML speakers' ss bass amps. Inductance sensors in the speakers simply "listen-in" on the signal. What a tube amp won't do (as well as an ss amp,) is
power and control that woofer. But in the new ML hybrids, it's not being asked to do that . . . . .
is it! ML finally came to their senses
after 20 years and provided the market with a "pre-biamped" hybrid electrostat. Thanks guys! Better late than never!
dneumann indicates TFK's in his C2300, but not what tubes are/were in his MC275. "Congested" sounds to me like a 'tube thing' and/or possibly speaker cables with way too much capacitance for stats (Cardas?). I also question why you give an ex-commercial photographer, with only a consumer's understanding of audio, any credibility? As a publisher, he gets lots of equipment to photograph, and play with, and yet he honestly thinks the "old days" of audio was 1983! Give me a break.
Here are the two reasons why (almost) all tube amps (OK, and a few 5-figure ss amps) bring out the best in electrostatic speakers; to paraphrase Steve Hoffman and Bill Clinton, "It's the midrange stupid!" and, it always follows that great midrange goes hand in hand with a solid, well-defined soundstage. Electrostatic speaker panels can reproduce the phase detail in a music signal with uncanny accuracy (assuming the speaker cables and the amp can deliver what the source and preamp send them.) It's the interaction (in the room) of phase-accurate sound waves that produces midrange presence and defined instrument locations. Solid state amps have a problem with this unless they employ carefully matched power output transistors (darTZeel, Boulder, anyone??) But tube amps do it like falling off a log. You don't really even need matched power tubes -- just ask McIntosh (to be fair, the Unity Coupled Circuit makes tube matching and even tube biasing of minor importance :yes
And even with a very pricey Class A solid state amp, you need more watts to drive a stat with the same precision as a lower powered tube amp. Why? Because thinking all watts are the same is a mistake young souls continue to make. Watts is NOT Watts! A watt is a product of current times voltage. You can therefore increase one while decreasing the other and still come out with the same number of watts. Relatively speaking, tube amps have a larger amount of current in each watt of output while ss amps a larger amount of voltage. That makes each type of amp better suited to satisfying the particular KIND (not amount) of power needed by different kinds of speakers; tubes for current--hungry electostats; and solid state for voltage-hungry electrodynamic (voicecoil) speakers.
Although ever since solid state came about there have been attempts to blend the two within a sigle amplifier, there are now (finally!) several serious products that attempt to do just that. To name three, the Lamm 1.2 and 2.2, Moscode 402 AU, and the new Aesthetics Atlas reviewed in Jan. Stereophile. Here's how they work: "Great--Sonics--Central" for any amplifier -- scratch that -- any
system, is the input stage (or gain stage) of the amplifier (and not the power output stage as so many believe.) So why not make the input stage out of (signal preserving) tubes, and the output stage solid state? Well, the answer is that it's hard to get little 9-pin signal tubes to control power output transistors. The Lamms are Class A and use ONE vacuum tube in their input stage. The other two use a few. You
can in fact get
input transistors to control
power output tubes fairly easily, but who'd want to do that? Answer: Audio Research, and it was a dismal failure!
Thank heaven this thread is about electrostats, or I'd catch hell for going off topic! I have used a few different amps with my CLS's over the last 20 years. SS and tube. All top of the line. The unbeatable (certainly by any ss amp with autoformer output
) Mark Levinson 23.5, a pair of monster 300W ARC monoblocks, and now my MC275 Mk4. I could never understand (back when I too listened to "folks more knowlegable than I") why my great ARC M300 Mk2 300 watt/ch monoblocks didn't knock my socks off like tube amps and stats are supposed to. Years later, I learned they had FET solid state gain stages (front ends) -- the last place in a system you want transistors!!
Besides having lots of current in each watt to lavish on electrostats, the MC275 has a current--controlled (as opposed to voltage-controlled) output stage. This happens because of the Unity Coupled Circuit I mentioned earlier, a good thing for stats I think, but something Frank McIntosh probably didn't even consider, since there
weren't any stats back then!!
