Questions about Mcintosh tube amp pairing with Altecs

McIntosh makes a ton of products, many of them are very pedestrian sounding (not special). The McIntosh MC275 is NOT one of these products. Buy confidently as this is really one of there more special amplifiers.

Matt M

I'm a Mac guy and have been for just over 50 years (June).
The first Macs I had were C4s (2) and a C8. MC20s (2) and a Mac 30 Kit.

They powered Imperial Horns and a Imperial Sub, Kits..

MC30s,40,60,75,100,225,240,275s. There is not a single one or pairs that don't sound great. I'm not a huge fan of the MC100 (mil spec ugly)

MC30 when done right are just wonderful. True lovers of great valves too. RCA black plate power valves with Tellies & RCAs for signals.  BTW all Mac like that combo.

The little guy MC225 is where a lot of folks mess up. They use an OLD type of cap that last just about 1000 years. IF they are good leave them alone, if you find a bad one replace the pair, NO fancy caps or polies it will ruin the sound. Check the resistors real close rebuild the PS and use good valves. One of a kind sound. Nothing like a 225

The amps you left out are the MC40s and MC240. I personally like the MC240. When rebuilt with just a minor PS upgrade, a couple carbon comp resistors and good PIO caps it is right in there with "the all time best" HOF crowd. Very special because of 6L6s and THAT transformer combo..

6L6 valve is very misunderstood. The mil spec version is one of the toughest valves on the planet.. I love the BASS response of a 240 not being pushed too hard on the bass but the right combo LIKE an efficient horn. The mids and highs.. Are just to die for.

The 6550 and KT88, (MC60,75,275) units can be harsh but usually it's because of the valve not the actual amp. GE 6550 and Golden Lyon type quality isn't cheap but the difference is night and day in a Mac using them. The new deal CE type transformers are different and sound different. I had 2 CE 275s I kept one. Good amps. They do run cooler than the older and sound cooler too.

 The BOMB is the early MC275s with a little work. 85+ watts per channel and will push those Alec's to there VERY best.

The signal valves are really important in regards to what to stay away from. Sylvania & PVANE, comes to mind. Unless it's for a certain application. That type of valve can be harsh and bright, remove bass duty and just push mids and highs It makes a lot of difference too. It depends on the application.

Macs plus 4 or 5

I'm a Cary fan too.. Just not sure with horns, for small planars, I haven't found a better combo than MY V12R.  A personal all time favorite of mine.. Right there with a Mac MC240 (Samra special).

I'm NOT a huge SET fan either. I must admit though I've herd some good ones.

A5's would be tempting to put with a great 300b set amp.
Maybe run without a pre if possible.

I had a Cary 120 running my Altec Maestro M500's. This model
was planned as the next upgrade to the 19. Then Altec folded.  
That pairing produced some good sound especially with certain instruments-Acoustic. 

Line Magnetic makes great sounding gear. 

If you love Mac then why not get the 30 or 60 Monoblocks?

Sounds like you are on the right track.

I think the MC 30s would be awesome. Finding a clean pair may be a slight challenge versus the stereo amplifiers but they do come up. The tube rectifiers are what I like about them. Also, I know my system has some other limitations that will be addressed in the next go around. I only get to purchase audio gear once or twice a year and amplifiers are my current focus !  Next will be turntable, arm, cart. 

A good alternative to the Mac amps are a pair of Heath W5’s. 25 watts using 6L6/KT66 pairs along with Peerless output trannies. I have a pair along with several different pairs of Altecs.

@jasonbourne52 I got both of your messages in my email account but one of them doesn’t show up here for some reason. I think you hit the nail on the head about it being a headphone amp. That’s what I was feeling but didn’t know how to express it. It has an incredible rich midrange but runs out of steam quickly. 

This is just my opinion.  I have 2 pairs of A7's, I believe the best speakers I have ever listened to.  One is 8 ohm, the other is 16 ohm.  I have listened to these with various different amps.  Audio Research (tube amp), Dynaco ST-70 (early rebuild done by Van Alstine the person, before the company he started), ATI, Linn, some others don't didn't set themselves apart, and last but certainly not least Decware. 

To me, the Decware SE34I.5 is pure lightening in a bottle.  Granted this is a huge 6 watts/channel but there is something magical about running a pentode EL34 as a single ended triode that has wow factor.  The efficiency of the speakers, which is similar to what you have, doesn't need much to make them sing.  When I got the unit it was like hearing things for the first time.  My son listened with me and he said it was like going from a low pixel tube TV to a 4k TV.  Everything is presented in the musical recording more perfectly than I have ever heard it.  Nothing is over presented or over driven and everything is there.  The most perfect balance I have heard from any system.  I understand firsthand why you seldom see any amplification Decware makes on the second hand market. 

If you go with the Mac, which is seldom, if ever a bad choice.  I'd be curious how they sound.  I was contemplating a Mac amp when I got the Decware.  Good luck. 

That’s an Avenue I had not considered. Decware was not even on my radar. Thanks for sharing your experience. I will research it !!   Adrian

Decware gets raves from everyone. Production backed up like many.

MC40 monoblocks on Altec Valencias. Audio Research SP8 preamp. Great musical combination, love it!
BillWojo