What McIntosh Amp With Thiel 3.6 Speakers?

My current main system has a Mac MC-150 Amplifier and Thiel 3.5 speakers. While I enjoy the sound of my system; I've wanted to upgrade to the larger Thiel 3.6s for some time. Not only are the 3.6s a newer model; but from listening several times, I've concluded they have deeper bass and a somewhat more balanced sound. Now that I have the means to make this upgrade, I'm having some doubts if my MC-150 can properly drive the 3.6s. I would appreciate some feedback regarding a suitable Mac Amp to pair with the 3.6s. I should also mention that I mostly play classical and pop music at low to moderate levels; and my listening room is approx. 20 feet wide and 17 feet deep.
I am very familiar with the Thiel / Mcintosh combination when I first bought my cs6 I was using a mc300 they produced a reasonably good synergy or so I thought until I bought a mc500 "what a difference" and then I upgraded my cables originaly I was using Nordost red dawn's I upgraded to spm's and the whole thing came together you know soundstage , balance from top to bottom and now I am sporting Valhalla's and I can say I could not be happier Good luck
I would highly recommend the MC-352. The 3.6's are not easy to drive and the 350 watts that MC-352 provides is just what you need. I had a chance to hear the 3.6's with Mark Levison No 335 and found the combination too cold and edgy. When plugged the MAC, the sound was transformed: smooth, musical, liquid and very dynamic. The Thiels tend to be a little bright in the upper mids and the Mac's smooth, rich almost tube-like midrange tonality really helped to tame things down. Great synergy. The same can be said about the MC352 and B&W Nautilus series, particularly 802 and 801 that also tend to emphasize the upper mids/lower treble and really require a serious amount of quality watts to sound their best.
I have a McIntosh MC300 connected to my Thiel 3.6's using Cardas Golden Cross cabling. I really like it. Some friends tend to think that my system is a bit bright but I don't think so. I am sitting a bit close to the speakers so this probably has something to do with it. I think people either love Thiels or hate them.....I love them. I will say this about the McIntosh/Thiel combo, the mids are just a bit thin. I borrowed my bother in-law's Classe 300 and the mids filled out somewhat. I had his amp in my system for about two weeks and then went back to my Mac. There was a definite difference, but I can't say that I preferred the Classe. I sat back and listened with my Mac back in my system and it was like returning to a very comfortable easy chair. I thought about changing amps but to this day I still have my Mac. It's always hard to give up that comfy easy chair.
We are Mac dealers - so let me prefix this resopnse with that statement.

Definitely do not drive the Thiel's with anything less than a MC-352. For two reasons - one power rating, and two autoformers. The MC-352 is the smallest amp Mac makes with autoformers, and they really help on speakers with erratic impedance such as the Thiel's. The autoformers effectively add impedance to the circuit which makes the speakers easier to drive and less onerous on the amplifier in terms of current demands, even when the speaker's impedance dips. Also you need raw horsepower to drive those speakers, particularly current. The higher up you go on the chain of Mac amps, the better off you will be sonically. The MC-352 is a great sounding amp and a very capable one at that. But frankly with your Thiel's you could enjoy better sound by moving up to the 652. You don't _need_ to, but it would be worth auditioning. I think you would find the improvement over the 352 significant.
Mitcheft is correct in his discription of MC-300. I used to own it myself before I upgraded to the MC-352. Although it may look like the amps should be similar, they are totally different in character. The MC-300 is a bit brighter in the upper mids and the treble, sort of glitzy, nice, but not perfect. The mids are nice but are a little higher pitched than the rich mids of the MC-352. MC-352 has beautiful, nicely resolved treble, a little recessed upper mids, rich and refined midrange, great bass with excellent extension and control. Both are wonderful amps, but MC-352 is a much better unit. It walks all over its older brother in transparency, dynamics, bottom end extension and control. At the same time it's lush and musical, never sterile or uninvolving. The bigger MC-602 is very similar and I really don't think it's worth the price difference, and I can't imagine any speakers that would significantly benefit from from such increase in power. The 350 watts of the MC-352 should be more than enough to drive even the toughest loads.
The 352 is a great amp and I agree it is a good choice here and anything above in the Mac line would be slight overkill but certainly if money is no object than the 602 would be nice.
Symphony Sound - Just a note: The Thiel's impedance is not "eratic", it's just low - under 3 ohms through most of the range, about double that in the low bass. The curve is actually quite flat, and the electical phase characteristics are fairly benign. But you are probably right about what to use.
Zaikesman, at the risk of being the victim of your wit for repeated offense, I belive the word eratic was used in the less frequently used sense of deviating from standard. Your point is well made and I'm sure you clarified this too many who otherwise may have been misled.
I own a pair of Thiel CS 2.3's, and drive them with Mac's MA 6900 integrated amp. It has autoformers. I support the above suggestion to use one of the Mac amps that has autoformes with the bigger Thiel's -- In general, I find the Thiel - Mac combo very satisfying.
OK, here's my totally wit-less response. ;^)

First of all, we both spelled the word 'erratic' incorrectly, which Symphony Sound did not. My apologies if I caused you any erraticism in this regard.

Secondly, there is a 'standard' impedance? Hey, everything's nominal, as they say, but you are correct inasmuch that Thiels are lower than most, and that the same may have been Symphony's point. (And, of course, you are right concerning my brilliant public service.)

P.S. - Try for another repeat, however, and you will be duly skewered. :-)

Erratic was a poor word choice - thank you for correcting me. I tend to use that word to describe impedance curves that are difficult to drive because more often than not the _are_ erratic in that they fluctuate like a roller coaster, but in the case of the Thiel's the problem is not with the variation.

The Thiel's impedance is consistently low, and relatively flat. It has a reasonably benign phase angle although once you get down to the range where the Thiel's impedance lies for the vast majority of the frequency range, even a slightly capacitant phase angle is going to complicate matters somewhat.

The point that I was trying to make was two fold: one the nominal impedance rating on the Thiel is virtually meaningless and certainly misleading. Second, because the impedance dips down so low, you really need a lot of current, and hence the bigger the amp the better. Err on the side of too much power.
Hackmaster, I don't think Thiel's nominal impedance rating is any more "virtually meaningless and certainly misleading" than most other speakers nominal impedance rating. In fact it's probably more meaningful and less misleading than most other speakers nominal impedance ratings for the very reasons you posted. Thiel readibly offers quite a bit of detail regarding the specs of their products including the minimum impedance loads.
I'm not trying to beat up on Thiel - in fact you are quite right that they are very good about providing information on the minimum impedance of their speakers, etc. I wish more speaker manufacturers would provide this kind of information and would be as upfront about the requirements of the amplifier driving them.

My point was not really Thiel specific - but that in _general_ when you look at the nominal impedance it doesn't tell you anything, and many people will use that figure as a criteria in choosing an amplifier. You really can't do that... you need more information.
I want to thank everyone for providing some very worthwhile information about the McIntosh amp I should be using to drive the Thiel 3.6s. In particular, I would like to thank Hackmaster for his suggestions; given that he is a McIntosh dealer and familiar with this speaker/amp combination. It looks like there will be a Mac MC352 in my future plans. Again, many thanks!
One correction: The MC352 is not the smallest amp McIntosh makes that does have the autoformers. The smaller MC202 does have them as well, and delivers 200 Watts into any load of 2, 4 or 8 ohm. You might want to give them a try first. I do have a Mc Integrated MA6500 and drive Shahinian Diapason speakers, whih are a notoriously difficult load to drive. Even the Integrated handles them very well, with no lack of dynamics. I have listened to other difficult speakers, e.g. Dynaudio's new C2, driven by "my" MA6500, and by a MC202 and a MC352. The difference between the MC202 and the MC352 was very small.
Hackmaster - I am shocked at a McIntosh dealer saying that the MC352 is the smallest amp with autoformers! And the 652?? What the heck is that??? If it replaces the 602, very few would have heard it at this point in time. This is just amazing. I am constantly surprised at how many dealers know nothing about the equipement they sell. Oh well....
A couple of notes...

With respect to my post earlier - I stand corrected. Serves me right for posting a response at 2 AM! MC652 was a typo. It's obviously MC602. And yes the MC202 does have autoformers although it is the only stereo amp from Mac that doesn't have the autoformers physically exposed (though the presence of multiple outputs taps is an indication that it is autoformer coupled)

And the MC6500 integrated does not have autoformers - the 6900 does (though they are not exposed, as with the 202) That is the main difference between the two although there are some other subtle differences. The Shahinians are tricky to drive but nowhere near as difficult or demanding as the Thiel's. The Dynaudio's are definitely tougher than the Shahinian's but the Thiel's still draw more current across the bandwidth.
Nevertheless - I still recommend an MC352. I just think you would be underdriving the Thiel's with anything less powerful in terms of current. Yes the 202 may have autoformers but it doesn't have the "oomph" of the 352. You can tell easily just by lifting up the 202 and the the 352. Then ask yourself which one stores more charge and delivers more current!
I have always been disappointed by the fact that the 202 does not have visible autoformers. That size amp is perfect for me but I wish it has the same autoformer look as the 352. However, if cost is not an issue, I would definately go with the 352. I have listened to one at length and just love it more than any other I have critically listened to (and the list is long). I have heard it play B&W N802s and Paradigm Reference 100s and in each case the sound was incomparable, with effortless presence, satisfying detail, and an incredibly smooth warm musical sound replete with impressive 3D imaging. I just get mesmerized by it and can't wait till I can afford one. Good luck - Arthur
Arthur - Did you ever find that 150 you were looking for?
nope! I found a few but none for sale. I am not in a big hurry anyway because I love my current McIntoshes and am very satisfied with them.
Arthur - It warms my heart to know that my 7100 found such a good home. Tim
Hi, i have a Thiel 1.6, can work with MC6600 ? (im sorry for my english)