McIntosh MC275 MkIV

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nsgarch

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My new baby -- finally, tubes again for my CLS's! And you all know by now how I feel about driving electrostats with a tube amp :bowdown:

Amp Manufacturer: McIntosh Laboratories
Model: McIntosh MC275 MkIV (MkV is identical except it has standard binding posts, but no input level controls)
Manufacturer's Suggested Retail Price: $3900
Used market average price: $2800 +/_
Basic Specs: 90+ w/ch 150w mono. SE and XLR inputs. (4) KT88 power tubes. Detachable PC.
Makes my CLS's sound like Quad 57's would like to sound if they could :rocker:

For a really big picture of the current system, click this link REALLY BIG PICTURE

For Dave and others who want to know the associated equipment (and to save MLC some bandwidth cost) please click on my system link. Thanks,
Neil
 

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. . . . . . . .and what tubes!

Makes my CLS's sound like Quad 57's would like to sound if they could
. . . . . . especially with $1200 worth (4) NOS Genelex Gold Lion KT-88's :D
 
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Marvelous...

Neil,

I love the MC 275 MK IV amplifier as well. :music: I wonder how the MC 275 will sound on ML's newest 'coming soon' CLX panels? - What am I saying... I'm sure it will sound wonderful. What's not to love? :music:

I know we have talked before about this wonderful amplifier and several other threads but I am still glad you to see your recommendation here. :D
 
All right . . . . . .

"Makes my CLS's sound like Quad 57's would like to sound if they could "Is that the extent of the review ?
I didn't realize I was supposed to discuss the sonics in more detail but I'm happy to do so, especially since I've heard my (17 year old) system with a number (3) of different amps.

I was encouraged when I bought my CLS's to go with tube amps because they "sounded the best w/ stats" (I didn't know one way or the other at the time.) I bought a new demo pair of ARC M300 Mk II monoblocks factory trioded (brought them down from 300w/ch to 140w/ch) They were a LOT of money ($11,000) in 1990! They sounded great to me (what did I know? ;) ) and they had (8) 6550 power tubes (and two cooling fans) per side! I have nothing against ARC products, but have since learned that their "house sound" is a littly "dry", not harsh or glarey like many less expensive SS amps (and the very expensive Krells :rolleyes: ) but just a bit uninvolving, though not fatiguing to listen to. This BTW doesn't apply (as much) to the relatively few ARC amps that use all-tube driver stages. The sound was excellent with good top-to-bottom reponse, and they had no trouble driving my original CLS II's (now IIz's). Soundstage/imaging was excellent, although I wish I'd known at the time, to use the softening switch and put the panels up on stands. Both of those changes would've brought out the midrange better, tightened the bass, and improved transient response, regardless of what amp was used.

I had to sell the ARC's 4 years ago because of apartment space limitations, plus 16 power tubes are not exactly what you want in Tucson AZ ;-) So I used my Levinson 23.5 (which I no longer needed to drive the subs, having purchased a ML Depth) The 23.5 is one of the GREAT ss amps ever made. I thought I was happy. It did sound better than the ARC's -- cleaner, quieter background, better dynamics. And the Depth was just perfect with the CLS's. One night, a friend who drives old Quad 57's with a Marantz 8b, and who knew how my system sounded with the ARC toobies, brought over an ARC VT130 (a great ARC all tube model) to A-B with the Levinson. Well, the ARC needed new tubes, needed to be biased, needed cap upgrades -- so it really didn't sound as good as the Levinson in all parameters except one: It had that you-are-there midrange ("breath of life" as Steve Hoffman says) which is the single most important ingredient for producing "goose bumps", and unfortunately missing from so many systems these days, even very expensive ones. Perhaps digital-only sources, unless very high end, aren't quite as challenging/revealing as tape or vinyl, but that "breath of life" midrange is what that everyone loves about the original Quad 57 electrostats (driven by a tube amplifier of course.) Unfortunately, the 57's don't do bass even as well as the CLS. Nor do they have the great top end extension of ML stats. But I wanted that great midrange for my CLS's, and I was going to have it or know the reason why!!

So I began researching stereo tube amps (no room for monoblocks this time) and I didn't want to return to the ARC designs. One of my absolute requirements was balanced inputs (not a feature on most tube amps) because I had a long pair of Purist XLR's and my Levinson 26s preamp had balanced outputs. (Elsewhere, I explain my preference for great solid state front end components coupled with equally great tube amplification.) I had also come to realize that the stat panels themselves don't really need gobs of power so long as the amp can deliver good current into their capacitive load. The McIntosh MC275 kept coming up, and I learned the latest model (IV and V) had undergone some major updates which I liked (they've been manufactured since 1961!) There's a dealer in Phoenix who sells both Mac and MartinLogan, who assured me it was a match made in heaven (although he said I'd need two -- which I didnt, you might with Summits, but not with Vantages) and I started looking for a bargain :eek: .

Although they're probably one of the best values in audio (McIntosh?!) at $3900, I found a used one in Canada (actually new in box) for $2700. I thought it was spectacular with my CLS's until my friend (with the Quads) brought over a couple of Telefunken 12AX7 driver tubes, which produced a quantum leap in sonics! And so I was introduced to the mad, mad world of Tube Rolling! About two months of experimenting, and $1200 worth of tubes later, I have the sound I was after -- the glorious midrange for which Quad 57's are (justly) famous, but without their shortcomings in extension, low frequency dynamics, and power handling.

I know a few Vantage owners who also love this amp, and apparently some Summit owners have now purchased them. I'm sure their sound is very similar to what I have with my CLS's (after a little tube rolling ;) ) because basically, it's the same assembly of parts (tubes and ML stat panels + self-powered ss sub) all without any of the expense and hassle of biamping.
 
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Love the MC275 and can imagine a wickedly synergistic sound with CLSs. I do have a question however. Doesn't the sub cause vibration in the tubes? I would imagine that the clarity/detail would increase if you could move the sub off of the amp stand.

Beautiful system all around. Enjoy it!
 
You can set a ML Depth (and I imagine a Descent as well) on the carpet with a cup or bowl of liquid on top, and you won't see a ripple when it's running -- it's that well balanced. (PS: My amp is also on Vibrapods ;-))
 
ML Summit & Mc Amplifiers

I have have been using a MC300 to power the ML Summits and the results were very disappointing... a very dull sound. I was on the point to sell the Summits.
On the advise of the ML users group I have purchased a new Sanders Sound System ESL amp.

It is amazing, it has brought the Summits to life...at last.

Clear and balanced sound across the full frequency range, more than sufficient power and does not heat up the room. It was designed for the electrostatic complex load which most of the amps. with transformer outputs cannot drive!

On top of this the customer service is excellent.

If you are in an quandry about choosing a new amp. don't decide until you have reviewed this model first.


John C
 
http://www.euroaudioteam.com/kt88diamond.php

Formerly the Tesla Vrsovice KT88. When your GLs go, these are the best KT88s I ever heard. I tried Tung-Sol 6550s, JJ Tesla KT88s, Shuguang KT88sm Sovtek KT88s. The EAT blows them ALL away. No very reliable though - The filaments can die relatively quickly.

I recommended these to someone who knows Ken Kessler - he said he'd tell him about them. A month or two later a glowing review appeared in Hi-Fi News:)
 
Hi justin. I bought two quads of used EATS with a friend for our MC275's and we had to return them. (I think they were really used.) He later bought a new quad for himself and really likes them; but I have enough GL's stashed away for this life, and they didn't cost me $1400+ a quad!!
 
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Neil - yeah, they aren't cheap...:D And the E.A.T. price is more than they were when I bought them as Tesla Vrsovice. I paid £360 or $720 per quad. BIG DIFFERENCE there, non?

I dunno whether you can borrow your friend's set for a while... I would try it if I were you. They were substantially better than anything else I tried, and Ken Kessler was really impressed. I was told by GT Audio that Tesla was told to copy the GL - and they made a REALLY good job of it.

To be honest, I'd be surprised if they weren't a bit better than the GLs... though that may be blasphemy!

I love the nostalgia factor old old tubes... the 1942 RCA 211s I run make me smile a lot:) I mean, how can they possibly blow the vast majority of solid staters away in the year 2008??? Excellent stuff.
 
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