To "tube" or not to "tube"

After a long musical drought (yup, divorced), I am now back in a position to upgrade. Have been wanting either the B&W N802 or Martin Logan Summits. So, for amps, what do you think, tubes, or SS for either?
For those speakers (802s) one needs lots of high power in their tube amp---how much $$$ are you thinking???
The Summits already have 400W of SS ICE amps for the subwoofers. So all you need is a MODEST powered HIGH QUALITY tube amp (for the screens). Stats and tubes are the "cat's ass," and you'll never go back once you're addicted.

If I had a pair Summits, I'd get the new McIntosh MC275 MkV. Not only did it better my Levinson SS 23.5 (and there's not much that does!) it's a BARGAIN @ $3900. I got one for my system. I have a pr. of CLS-IIz and a ML Depth - pretty much amounts to the same thing as a Summit, though I like the sound of my setup just fine TYVM. (see system)
hey george, well I'm hoping to to keep my budget for amp and pre under 5k.(if AG comes thru) My old set up was BW N803's powered with matching Classe gear, a nice CA300 and CP 50 pre with a matching Classe CDP, I think that would have handled both these speakers well, But I heard a set Of Summits out in Seattle that were powered with Mac,s ( I forget what pre's) and it knocked me out.
JB a lot of people use a pair of (mono paralleled) MC275's (150W ea.) to drive Summits. The nice thing is you could get one now and use it in stereo (they actually produce 95+ watts/ch), and add another one later and run them as monoblocks. There are some used MkIV on AG now. They're the same as MkV (which now has real binding posts ;--) You could also get a used C 2200 preamp (total = $1k over your budget) or the smaller C 220 preamp (total = right on budget)
duly noted! Thanks,
hi nsgarch:

i need your advice. do you think there is much of a difference between one 275 and a 2102 (100 watt) driving a pair of magnepan 1.6 ?

i was told by the technician at mcintosh that when bridging the amps, the sound of the 275 changes. it loses some of its tubey quality. the overall presentation of two 275 amps is supposedly more transparent than that of one 275.

i'm also not sure what the difference is sonically between the 100 watt mac and the 275.

thanks for your input.
I have the 2102 and i love it. It can sound better than many a more expensive amp. i like it so much I now own two of them which I am using in a mono-bidged configuration.
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 ;--)
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.
Tennis, did you get a IV or a V? If a IV, I can send you some pics showing a slick way to hook up fat speaker cables. Either way, I know you'll love the amp. It's actually quieter and more detailed than many top notch SS amps -- which I don't expect you to believe until you hear it (with Telefunken 12AX7's ;--)

hi neil, i don't expect to use telefunken 12ax7. i will use mullard 12ax7 or ge 5751 or rca 5751. i hope the amp is not too detailed. i may also try mullard 12at7 or rca 12at7.
hopefully the amp will be come with 6550, not kt88. i have no idea which 6550 tubes are mellower than current tubes. any ideas ? i am purchasing a mark V, new.
Tennis, congrats! You're going to really love that amp! The power tubes the MC 275 comes with are KT88, either Electo Harmonix (round holes in the plate) or Svetlana Winged "C" from the St. Petersburg plant (square holes in the plate.) The Penta KT88SC copy (SC stands for "strict copy") of the GEC Gold Lion/Gold Monarch KT88 are suposed to be the ones to have. I just ordered a new matched quad from a member for $100 shipped. I'll let you know on those. As for 6550's, you can also run them in this amp, but for my money, they're not as nice sounding a tube as the KT88. (Maybe a teentsy bit more power though.) The amp has neither bias adjust nor auto-bias; it's not necessary for the Unity Gain circuit design. It's good though to have matched pairs of power tubes and gain multiplier tubes in each channel.

For the 9-pins, I will be trying Mullard, GEC, and Amperex/Holland in addition to the Teles (what's up with the RCA's?). All I know is, the McChina's suck, IMO ;--) The tubes that make the most difference in sound are the three 12AX7's. Or just the two 12AX7's in V2 and V5 if your using the balanced inputs.

I'll be anxious to know how it sounds driving 1.6's. However, mine sounded like crap for the first five hours! Tubby, boomy bass and grainy mids, yuk! So do give the amp a 50-70 hour break-in before you evaluate it ;--)
hi neil:

what fo you think will happen if i use lower gain 12ax7, namely 5751 ??

according to mcintosh, changing tubes will not change the sound of the amp very much. a dealer told me that the 6550 gives a more romantic sound than the kt88. in any case, i won't be getting the amp for about 10 days.
I don't believe the 12AX7 does gain multiplying, but you shouldn't take my word as I'm not a tube circuit maven ;--) Check with McIntosh technical support.

I know what everyone connected w/ McInt. says about tubes not making a difference. All I can figure is they're all listening to McIntosh speakers ;--)

As for 6550's, I had 8 Svet. Winged "C" (per side!) in my ARC monoblocks, and I wouldn't characterize them as "warm and romantic". More neutral and dry. Now maybe that was just the ARC amp, I don't know, but many audiophiles and lots of electric guitar players seem to favor the KT88's, which let's face it have only started to be re-issued in quantity relatively recently.
Nsgarch, You (and the rest of you guys) have been a big help, given me lots to think about, I like the idea of 275Mcs mono blocs for either speaker set ups, so will be on the lookout. the next question of course, is pre-amps... And to Beheme, couldn't have said it better myself.