McIntosh 252 or 275 for my B&W 804s?

Well,
I just took the plunge about a month ago and picked up a MC 275 V. I first upgraded from all solid state to a Modwright SWL 9.0 tubed linestage and a Mark Levinson 23.5. That was a huge change ... probably the biggest for me. I like the control of the SS amp and the smoothness of the tube front end. It really took the fatigue out of the all solid state system I was running. Again, this is just my experience – I don’t meant to knock anyone in love with their “all solid state setup” … no two systems are the same after all.
I am running much smaller Aerial 6 speakers, so I don’t think it's a 1 to 1 with your 804’s but I thought I would throw in my two cents. I was so very happy with the Modwright/Levinson combo that I purchased a Levinson 360S DAC and a No. 37 transport. I was all ready to call it good when I heard the Mac 275 and Dynaudio Confidence C2's. Lucky for me I am very pleased with my current setup and I'm at a point where I don’t feel like jumping every time I hear a truly spectacular setup. “Somehow they never quite sound that good when you em home” I have my two channel setup in a converted bedroom (12 X 15) - so the speakers don’t need to work real hard to reach a desirable level. The Aerial 6’s are a fantastic little speaker but nothing like the Dynaudio to my ears. One look at the price tag on the C2’s and I could safely pass them off for the distant future but the Mac tube amp was do-able. I really got the itch to try a MC-275 after that demo. It didn’t take long before I pulled the trigger and one arrived at my doorstep.
The Mac tube amp was really quite fantastic – the demo ran for over an hour and I was significantly impressed with what it “could” do. I had purchased a few tube amps over the years and really liked the midrange frequencies in particularly the vocal range so I was hoping for the same magic as the demo. To make a long story short … I wasn’t all that blown away. It didn’t have the same effect as the tube front end and SS amp. I am now looking to try a SS front end and the MC-275 just to see what effect it will have. Just for kicks mind you … My guess is my speakers just don’t fit well with the combo. I imagine the B&W 804’s and certainly the 802’s would benefit greatly from the 275’s smoothness. I guess my system has enough of what I like not to have as much of an effect on me. I will give it a few more weeks and then switch back. I will go back and forth through the summer and probably park the 275 in the fall. I guess ultimately I might go with the Dynaudio’s and two MC-275’s but by then it might be B&W 800’s or Aerial 9’s.
As for advice – I gotta go with the tube linestage first … try the Mac pre with the Rotel amp. I’d just about bet it will reduce some of the fatigue from the all solid state setup. You might just fall in love. I made the mistake of demo-ing the 804’s with a cold solid state setup about four years ago and decided against B&W … I later heard the 800’s with a Levinson amp and thought it was da bomb. I have since heard the 804’s powered with an ARC tube linestage and kicked myself for not picking them up. The difference was astounding. Nothing against your current setup … but I think you will be amazed at what tubes will do for you. I am running an all solid state Rotel HT system out in the living room and I rarely listen to music out there anymore.

With a room that large, you really need more bass IMO. Bass is not to be underestimated in the overall scheme because it does much more for soundstaging and resolution than you might think. It is the foundation on which all else is built - and you know what happens to a house with poor foundations... The biggest upgrade in overall sound quailty you can make today would be to get bigger speakers or a subwoofer. Especially with 804s. I really like those little speakers but to get much bass out of them, you have to really whip 'em hard. The latest 804S is not as bad as the N804 but even still, I think they get overlooked by many because they are rarely used in a room small enough for them. Their bass remains tight and guarded.

Now, having said that, comparing a 252 with 2x275s is very interesting. I personally haven't heard 275s in mono but I have chatted with a couple guys here who use them that way, and I briefly had two 240s in mono (I only have one now).

If you don't mind replacing the big tubes once a year and the little tubes every other year (not very expensive), can handle a lot of heat in your room, and don't run the risk of a child or pet breaking tubes, then a pair of 275s gets my highest recommendation. This arrangement will allow them to handle the low impedences of your speakers much better than a single 275 would and give you lots more power and headroom which your amps, room and speakers need to sound their best.

The MC252 is the more practical choice here because it gives off little heat, is much more compact, has more power, has a larger damping factor, and has a much lower price tag. But if you only really care about the sound, you have to go with 150W of tube power.

However, you can't just go out and buy a pair of 275s and then use a Rotel preamp with them! :) Remember that a stereo is a series chain and so only sounds as good as its weakest link.... I would suggest that you get one 275 and a C220. Down the road a bit, you can add the second 275. Two 275s will sound much better than one. This is one of those rare instances when 1+1 = 4.

This is an EE geek technicality but I don't know why McIntosh has "mono bridged" on their website because this is incorrect. The 275s are actually "mono parallel" which is much better than bridging for modern speakers. The difference is that parallel halves the output impedance whereas bridging doubles it. So you get higher current in parallel and higher voltage in bridge. Power is voltage x current so their ratio can be either for a given power rating and impedence.

Either way, you will get much more bass out of your speakers with these McIntoshes than you've been getting with your Rotel. I am sure of that. But seriously consider a sub at some point, or at least a home demo of one, just to see what you think. You might be surprised at how much you can improve your Rotel simply by adding a sub. It still won't come close to fancy Mcs but it will bring you a whole new level of enjoyment in the meantime.

Arthur

Horseface: when are you planning to try the ss pre with the 275? Would be interested in learning what you thoughts are. I'll try to get to audition the 275 and a ss pre, but would be valuable to know how it sounded to you, in a known setup. BTW, no ofense taken about my setup...I'm aware of it's limitations!

Arthur: Unfortunately I bought my speakers before moving to this place and never thought I would end up with this large a room. And yeah, wasn't intending to run two 275s with the Rotel pre. I did see it as a path down the road. I can kind of follow the EE talk (being an ME). My dealer said bridging these would generate twice as much distortion. Your thoughts? Also, why using these bridged would required replacing the tubes every year?

Thnaks both. Very informative!

What your dealer has in mind is that paralleling them makes each produce twice the power but this is incorrect. It is the two 'together' that makes twice the power.

A single MC275 produces 75W x 2 channels = 150W total. A 275 wired in mono will produce 150W x 1 channel. It is still the same amount of power (just one less speaker) and so distortion and tube usage is theoretically the same too. Assuming the load (speaker) is the same, which obviously it is, so you would just change taps accordingly. If you don't use the right tap, you might get a little less or a little more distortion depending on which way you go, but all in all, isn't much difference as far as the amps (or tubes) are concerned.

Arthur

Well I have 2 275's (new mk V's). Here is what I wrote about thme when I compared them to the ASL Hurricanes. BTW, the newer 275's are more powerful rthen the origional. More like 80-90 wpc and 180-190 in mono.

I wrote in one of the threads the following regarding two MC 275's vs ASL Hurricanes:
Well it's been at least 5 weeks with one McIntosh MC-275 amp in my system and now I have, for over a week, installed the second one and I now have two mono MC-275's. So let me share my experience.

I'll cut to the chase and say that one mono amp is very similar to two. One 275 (rated at 75wpc) is powerful. Two 275's @ 150 wpc is more powerful. What do I hear? In a word "relaxed". A little more control but a bit more relaxed overall.

My comments of the 275 therefore will be generally a comparison of one (1) 275 (2-sounds pretty much the same with the additions above) versus the ASL Hurricanes DT 200.

Here are the pluses of the Mac over the Canes:

First- I got my mid bass (and bass) back in spades. One of my complaints with that the Hurricane amp was that it had a higher sensitivity compared to my other electronics. I wrote in my review of the Hurricanes: "The sensitivity of the Hurricanes was much higher than my previous ARC amp and therefore, I needed to fool around with the controls on my Infinity crossover to boost the output of the bass columns. The higher sensitivity made amplification of moving coils much easier, but seemed to be bright ,a bit edgy and the upper bass/mid-bass was missing. However, I was struck, immediately, with a new unveiled sound that spread instruments wider across the stage with much more clarity than before."

I am not an engineer nor a tech so what I may be explaining to you may not, in fact, be the reality. However, with the Mac in my system it mated better with my Aesthetix Calypso and reintroduce better mid bass and bass. How this could happen and be, since my bass columns are driven by a separate amp, I am not sure. I'm just the reported.

Second- The Mac is very clear and solid. It is there in your face. There is no drift or sway and it makes you feel like the amp runs at more power then rated.

Third- It is silent. And this is a tube amp? Wow.......

Now here are the ASL's pluses:

First- Stage width with the Mac is good. With the ASL it is great. The ASL add 5-7 more (imaginary) feet per side to the orchestra

Second- The ASL Hurricanes seemed more delicate and cleaner. Less colored? Maybe?

So here I am sitting with my system, enjoying my music and the biggest plus of all (Mac vs ASL) is that I AM LISTENING.
The Mac's have been on without a hitch. Knock on wood. However, just the feel makes me certain that the Mac's are far better in construction (far) then the ASL.

Remember, however, ASL has come up with a better Hurricane and I have not heard it or seen it but I must believe it has to be more reliable then the original. I just could no longer live with break downs with hurricanes.

Finally, if anyone is thinking of a Mac I say "YES". It is quite a wonderful amp with some character and style and plenty of power. And it keeps on running.......

P.S. I have not yet listened to the Mac with better KT88's or x7's or t7's which I plan to as I expect this would provide an overall better sound.