Curious about the latest McIntosh MC75 tube power amplifier

[jdandy]

John.......Thank you for the insight to your current MC75 arrangement. MC75 amps seem to be as scarce as hen's teeth. My MC452 is doing justice to the living room system but the MC75 flame is still flickering.

[tgmacgrove]

I am a current user of the MC75 amplifiers with a C2300 preamp. Speakers are a recent version of Quad electrostatics. My speaker choice shows my preference for midrange honesty, arguably at the expense of other attributes. I appreciate that this combination would not be suitable for everyone, or for all applications. That said, I can, and do, listen for hours without fatigue and without my mind wandering away from the music; it, and not the gear, holds my attention.

If I may advise, allow yourself some slack for straying from your initial MC275; nothing wrong with trying a different approach. But if you miss how that amp worked in your system, you are sure to find a “rightness” with the MC75s. If you can find a pair, I believe your hunch about them will prove correct.

Somewhat related: I also have a C22 III. My ears prefer the C2300. Some maintain that it is the same preamp, and it may very well be. But the C2300 strikes me as being slightly less forward than the C22 (same tubes in each). Certainly my preference; the C22 III is a great preamp and I will be keeping it.

Finally, I see you had a pair of MC30s in the late 1960s. That’s about the time I started on my McIntosh path. My friends bought beater cars; I bought Mac gear with my high-school part-time job money: a C22 (late production), an MR-71 (same), and an MC240 (same; I sent in for the tube cage). The beater cars are long gone. I still have all of the original Mac gear. And I’ll be keeping the MC75s too.

With a little patience, I’m sure you can find a pair. Best wishes!

[jdandy]

tgmacgrove.......I appreciate the insight on your C2300 and MC75 setup. I would agree the C2300 is a superb tube preamplifier. I have mated it to quite a few different McIntosh amplifiers and it never failed to perform flawlessly. I expect a pair of MC75 tube power amplifiers will fit in perfectly.

[MisterBritt]

Originally Posted by John Jordan

Hi Dan-

Perhaps something in my journey to the MC 75's might be of help to you.

When I looked in to replacing my MC 352, we spent approx 4 hours listening at Audio Classics 352 to 452 to 275 back and forth. The final choice was the 275 with the possibility of purchasing a second in the future and/or changing my speakers.

At the time I had Mc LS 360 speakers with an efficiency rating of 88 db. While the 275 drove them quite well, there was some confusion at higher volumes. Getting the upgrade bug, replaced them Legacy Focus SE's. Certainly preferred the sound and an efficiency of 95.4 db received the "confusion."

A year later and seriously considering a second 275 finally gave the MC 75's a listen. I can really say there was a night and day difference between the 75's and the 275! Considered trading the 275 for a pair of 75's but kept the 275 for the lows and 75's for the mid/highs. They pair together well for a bi-amp set up. I have tried switching the 75's and 275 around. The bass did get a bit more defined but the mid's and uppers got lost. Considered another pair to replace the 275 but did a pre-amp upgrade instead.

As a side note, the 75's seem to put out less heat than the 275 and it is true they have the same transformer as the 275. They fit quite well where my 352 once sat so they should fit quit well where your 452 now resides. Lastly, it is my understanding that McIntosh ceased production quite abruptly on the 75's and dealers did not have an opportunity to do a "stock-up" if desired.

I enjoyed your post. You had mentioned the possibility of bi-amping the 275s with the 75s. Or alternately simply running four 75s, two per channel.

I own a pair of 75s and have been curious about the XLR input and output feature. I glanced at the owners manual but didn't get a clear reading for myself on what that's all about.

Question: If you wanted to bi-amp with four 75s, could you economize on an expensive long run IC between the preamp and the 75s by running a single IC per channel to the first 75 (with the speaker cable connected to the lows) and then "jumping" via the XLR output to the second 75 (with the speaker cable connected to the highs)?

Does anyone know how that works?

[damacman]

Yes, you could certainly do that. That is unless you elected to also use an electronic crossover network between the amplifiers for each channel.

[leftside]

Originally Posted by dcanlas

Dan, I have the anniversary edition and I loved it...it has the magical midrange of a Tube Amplifier, superb soundstage depth, and Bass are tight and clear!

Highly recommended!

Agreed. Best amps I've ever owned. I use them with the C500T and Dynaudio Confidence C1 Platinum. These speakers are meant to be quite hard to drive, but as my room isn't huge, the MC75 seem to do a fine job. I went through a number of years continually upgrading my Mac system, but I seem to have stopped now.

[John Jordan]

Originally Posted by MisterBritt

Question: If you wanted to bi-amp with four 75s, could you economize on an expensive long run IC between the preamp and the 75s by running a single IC per channel to the first 75 (with the speaker cable connected to the lows) and then "jumping" via the XLR output to the second 75 (with the speaker cable connected to the highs)?

Does anyone know how that works?
]

MrBritt-

The preamp connects to the MC75's input and then the MC75's output go to the 275 input. So a cable just long enough between the two amps works.

Speakers terminals of the 75's go to the mid/highs and the speaker terminals of the 275 go to the woofers. The 275 is set to stereo. The input sensitivity needs to be set the same for all amps. You will need two runs of speaker wire; I use Belden 10 g purchased from BlueJeans.

[MisterBritt]

Originally Posted by damacman

Yes, you could certainly do that. That is unless you elected to also use an electronic crossover network between the amplifiers for each channel.

Originally Posted by John Jordan

MrBritt-

The preamp connects to the MC75's input and then the MC75's output go to the 275 input. So a cable just long enough between the two amps works.

Speakers terminals of the 75's go to the mid/highs and the speaker terminals of the 275 go to the woofers. The 275 is set to stereo. The input sensitivity needs to be set the same for all amps. You will need two runs of speaker wire; I use Belden 10 g purchased from BlueJeans.

Thanks guys. That's pretty much how I imagined it would work. I appreciate the replies.

[ckebsch]

they have a set in West Palm Beach, FL at Audio Advisors 561-478-3100 open m-f only.

[jdandy]

ckebsch.......Welcome to Audio Aficionado. .

Thanks for that information.