To "tube" or not to "tube"

Hi Tennis,

Let's see, you've managed to bundle quite a few topics within a short inquiry, ha HA!

Addressing sonics first: Though I've not personally A-B'd those two amps in a controlled setting, I think sonic differences between them, using the same KT88/6550s, 12AX/AT7's, would be very small. I know from my own experience, that tube rolling, especially the small driver tubes, can alter the dynamics, air, and detail of these amps quite a bit -- my favorite small tubes (so far) are Telefunkens. Many folks are happy with the stock "McChinas", not me ;--)

All that said, these two amps are different, from a circuit design POV. The latest 275 has a larger new 470V power transformer serving only 2 power tubes per side to achieve an amazing 95W per channel into 4/8/16 ohms. Whereas the 2102 uses the same transformer, but serving FOUR power tubes per side to achieve probably 125W/ch. So, you're running double the tubes per side and only getting 30 more watts. Both use the famous patented "Unity-gain Circuit", HOWEVER, the 275 uses THREE of the small gain/driver tubes (per side) to drive the TWO power tubes (per side) while the 2102 uses only TWO gain/driver tubes (per side) to drive the FOUR power tubes (per side). Bottom line: the 275 is (and always has been) a marvel of efficiency among tube amps, which, as a class, are not noted for their efficiency ;--) Additionally, the economics of using one amp in stereo mode, but eventually having two units in bridged mono mode, favors the 275, in both actual acquisition costs, and in dollars per watt.

As for changes in sonic character between stereo vs. mono operation, I've heard no comments. For the 275, the mono/stereo discussion centers around more headroom/power in mono mode, for getting through big, dynamic passages with ease. Salespeople say that with some speakers (like Maggies?) that might be a struggle in stereo mode. Well duh!!

Which brings me back to your first question about suitability with Maggies. For an economical setup (meaning a single stereo amp or pair of monoblocks,) I'd advise against Maggies and tubes. Maggies need power, and the cost of a tube amp with an honest 200 to 400 watts a side (depending on which Maggie) is exhorbitant. Anyone willing to spend that much money to combine tubes with their Maggies, would be better advised (both economically AND sonically) to biamp, using a good outboard crossover, like the very versatile and quiet Bryston 10B, then driving the bass panels with a single Bryston 3B or 4B, and the ribbon (or quasi-ribbon) tweeters with something like a single MC275. Now that would indeed be very sweet, but you're talking a LOT of hardware. AND, in addition, with the smaller Maggies like the 1.6, you'll need at least one sub regardless.

I gave my Maggie Tympani 1-D's to a friend who ran them with a ML 23.5, which is one of a handful of SS amps that approach tube sound. The Levinson 23.5 is not hard, has a wonderfully detailed soundstage, but still doesn't do too much ambience, timbre and decay. Sigh ;--) However, if you want a simple and beautiful setup with Maggies, that's the way to go IMO (and I happen to know where there's one for sale ;--)

I think a lot of folks don't realize that Maggies are not electostats and, except for their ribbon tweeter, don't really benefit from tube electronics. On the other hand, they are modestly priced for a (very articulate) panel speaker with real rock music power handling capacity.

thank you for your comments, nsgarch.

at the moment i am using a pair of vtl deluxe 120s to drive the 1.6s. it is not possible to biamp. for a difference of 30 watts, and based upon your comments, i'd say a single 275 might be worth a shot rather than the 2102. if i want more power, i can always add another 275.

i have heard magnepans driven with solid state amps--levenson, audio research and nelson pass and have been very displeased with the treble response. i am always willing to sacrifice dynamics and bass articulation to get a more pleasant sound in the upper mids/lower treble.

Tennis, the 275 (especially the new IV or V) is an unusual and outstanding tube amp. One, in stereo, will drive a Maggie 1.6 full range quite nicely as long as you are not going to ask it to do rock, opera, or orchestral at high volume. When you want that, you'll have to add another one and change them to monoblocks, however that is still a very cost-effective path to what you're after.

A purchase tip: The Mark IV is being phased out and the Mark V phased in. There is no difference in circuit or sonics. The two differences (if they're important enough to you to buy a new V vs. a used IV) are:

1. The V is lead free so it will comply with the new European import laws.
2. The V has regular five-way speaker cable binding posts, whereas the IV has the old fashioned barrier strips and screws. So if you have spkr. cables with big spades, it takes some tricks to attach them in a workmanlike manner ;--)
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Joeb, good move, treat yourself man, audio is the most loyal lover!

thanks again, nsgarch. i found a dealer in wisconsin and got a good deal on a 275. i may buy a c220 as well.
i am also considering an audionote m2 and a navison mk 3. hopefully one of them will be warm enough.