MC225 - What makes it so special?

[kippy]

I have fallen in love with my MC225. It's on HF duty with my Heritage Jubilee speakers. It's a little noisy but otherwise the sound is absolutely beautiful. Very musical, detailed enough (although slightly less so than the J2 in my possession), has an amazing soundstage and makes me fall in love with each song I play with it. I'm so impressed and amazed with it. 

 

What is it about this amp that makes it sound so good? Are there others that sound this way? And how does something like the SIT3 compare? 

 

I feel very fortunate to have read all the posts on this forum for the last 4-6 months. I've learned a lot from all of you and would not have arrived at this audio bliss without the knowledge you have shared here with each other for so many years. 

Edited June 17 by kippy

[jwc]

I have read up on McIntosh equipment for years and own quite a bit of it.

 

If you ever search "the Best McIntosh amplifier ever", the MC225 comes up quite a bit.  It also is a fav of many of the Singled ended lovers but we know it's not single ended.

 

I own one and will eventually let John Warren get his hands on it.   My advice would be to never let go of it.

 

jc

 

 

[jwc]

"""What makes it so special?"""

 

I'm not the expert.  Consideration would be the point-to-point simplicity, McIntosh transformers, and 7591 tubes.

 

jc

[lighting guy]

Hi Kippy, I haven't heard the 225, but I have heard a MC240 on a pair of Khorns.  You're right, they are a great match.  Maybe a little rolled off on the highs if I remember correctly.   This was at a Bay Area amp shootout we had 15 (or more) years ago, so my memory is fuzzy.  My favorite is still single ended, I'm a little partial in that regard.  In my opinion, the winner that day was a pair of Welbourne Moondogs (2A3 based SET), mainly for its 3D soundstage.  Never heard any First Watt, but I'm sure it's great.

Darrell

[kippy]

6 hours ago, jwc said:

I have read up on McIntosh equipment for years and own quite a bit of it.

 

If you ever search "the Best McIntosh amplifier ever", the MC225 comes up quite a bit.  It also is a fav of many of the Singled ended lovers but we know it's not single ended.

 

I own one and will eventually let John Warren get his hands on it.   My advice would be to never let go of it.

 

jc

 

 

 

It's a funny thing you mention John; a very knowledgeable member of the forum recommended him as a restorer. I just sent off pics of the inside and outside to John earlier today to assess the condition. If you have ever wanted to ogle the insides of the MC225, here you go: https://photos.app.goo.gl/bkqDNE5iMxEf9CZg7

 

Where on your 225 can you see the year of manufacture? 

 

I agree with you that the relative simplicity of the circuit is part of the magic. I started watching this vid to understand it. Can't really discern from the details what creates the magic yet: 

 

Edited June 18 by kippy

[kippy]

5 hours ago, lighting guy said:

Hi Kippy, I haven't heard the 225, but I have heard a MC240 on a pair of Khorns.  You're right, they are a great match.  Maybe a little rolled off on the highs if I remember correctly.   This was at a Bay Area amp shootout we had 15 (or more) years ago, so my memory is fuzzy.  My favorite is still single ended, I'm a little partial in that regard.  In my opinion, the winner that day was a pair of Welbourne Moondogs (2A3 based SET), mainly for its 3D soundstage.  Never heard any First Watt, but I'm sure it's great.

Darrell

 

Hey Darrell,

 

I've heard that the MC240 is the only other amp that has the sweet magic of the MC225, in fact some accounts say the MC240 might be a tad sweeter. It's spot on that the highs seem softer on the MC225 and that is definitely what I was looking for...although I would say that it doesn't seem like the highs are rolled off in an unnatural way. The highs are still clear and I can see into the mix nicely but there is never a shred of sharpness in the sound. 

 

You mentioned a Bay Area amp shoutout; I'm in the Bay Area myself (Pacifica) and would be up for another shootout. I'd be happy to host if others are interested. 

 

I'd love to hear the Moondogs or any other SET based amp. For now at least, I have the J2 and MC252 amps here as well. 

[lighting guy]

Hi Kippy,

I hope you get to host another get-together, they certainly were a lot of fun, but the primary participants of our group have either died (Josh Nichol) or moved away (myself and others).  Maybe post something in the Lounge section?  There was another group, the Bay Area Audio Asylum, but it fractured apart around 2010.

If you PM me I can send you a small list of K avatars who may still be around and interested.

Darrell

[Toz]

My buddy in high school had an MC225 he snagged from a closing movie theater. This was over 50 years ago! He had it cobbled together in his bedroom driving some Large Advents. There was definitely some magic there. The preamp was a dynaco. My biggest fascination was his Fairchild 16" transcription table that came from the Fines of "Mercury Living Presence" fame.

When he got an SME 3012 tonearm, I got his Micro track 306 which I use to this day on my Rek-O-Kut G2 16" Transcription.

  The McIntosh 225 is responsible for starting me off right!

[kippy]

Cool story Toz. I wonder if the McIntosh guys would build a circuit and then just listen to it with music and then make adjustments to it based on how it felt to them. Or was it pure science and engineering, just THD and responses curves and luck that this amp has magic to it.

 

I’ve read about how Nelson Pass makes his First Watt amps and there seems to be equal parts science and romantic listening/adjustments to the circuit. I’d love to imagine this was true of McIntosh as well.

[kippy]

It is said that success has many mothers and surely engineering efforts have many contributors, but was Sidney Corderman the engineer at McIntosh who designed the MC225? https://www.mcintoshlabs.com/brand/news/Sidney-Corderman

[hizzieallen]

I have a C11-MC225 paired with some Forte IVs. The combo is magical. I've always heard that the simplistic design of the 225 and the 7591 tubes is what makes it so special. I'm also of the opinion that low to medium powered tube amps are among the most musical amps out there. The 225 falls into this category. One other thing I will say about the 225. The amount of bass that its able to produce is very surprising.

[Toz]

My gut tells me McIntosh was first and foremost an engineering company in the time period of the 225. 

  Now as far as listening tests and Nelson Pass go, other pioneers at that method were Conrad Johnson. 

Their early tube amps and preamps had simple circuits and high quality components tuned by ear to sound great.  That's what I run today to power my Klipshorns and there is magic in spades.

[kippy]

On 6/19/2024 at 1:00 PM, hizzieallen said:

I have a C11-MC225 paired with some Forte IVs. The combo is magical. I've always heard that the simplistic design of the 225 and the 7591 tubes is what makes it so special. I'm also of the opinion that low to medium powered tube amps are among the most musical amps out there. The 225 falls into this category. One other thing I will say about the 225. The amount of bass that its able to produce is very surprising.

 

I am beginning to wonder myself about the connection between low-powered amps and horns. I had previously powered the Jubilee speakers with a pair of MC252s. Solid state, powerful amps that mate nicely with less efficient speakers. I kept feeling that there was too much energy in the mid and upper registers. Something wasn't quite right. When I swapped in an MHA-150, the sound improved significantly. I swapped between the two multiple times and felt the same effect. Logically, the MC252 produces clean, distortion-free sound and the Jubilee horns were consuming less than a watt of power at 70-80db and yet I felt overwhelmed each time I used them with the Jubilee speakers. I observed the same impact when swapping in a J2 and the MC225. The same MC252 sounds fantastic when paired with my lower-efficiency speakers (Sonus Faber). 

 

It's a small dataset ^ but seems like the HF horns *don't* benefit from extra reserve power...I have observed differently for the LF drivers on the Jubilee. The extra power helps and I have clipped the MC252s even when playing near 105db.

[kippy]

On 6/19/2024 at 1:24 PM, Toz said:

My gut tells me McIntosh was first and foremost an engineering company in the time period of the 225. 

  Now as far as listening tests and Nelson Pass go, other pioneers at that method were Conrad Johnson. 

Their early tube amps and preamps had simple circuits and high quality components tuned by ear to sound great.  That's what I run today to power my Klipshorns and there is magic in spades.

 

Which Conrad Johnson amp do you like?

[Toz]

I have a Conrad Johnson MV-45 push pull EL34 that is rated at 45wpc.  Presently,  I have the EL34's wired in triode configuration so the output would be roughly 22wpc.

 I also drive the Khorns with a 5wpc Pass designed mini ACA I built from a kit. 5 watts plays louder than I ever care to listen. 

  I've used plenty of SS amps over the years with various results.  The CJ MV-45 with just about any tube set I've tried wins every time. It's just a sweet almost lush sounding amp with three dimensional imaging. It doesn't give up any detail or dynamics to anything else I've tried. 

  I've never owned any McIntosh, I've only experienced it at friends places and in shops. I wouldn't pass up an opportunity to own some Mc gear though. I get the impression it is very reliable, which isn't really the reputation associated with CJ. I've been able to affect my own repairs on my amps over the many decades of ownership, so I'm not really complaining about reliability.

[kippy]

On 6/20/2024 at 10:07 PM, Toz said:

I have a Conrad Johnson MV-45 push pull EL34 that is rated at 45wpc.  Presently,  I have the EL34's wired in triode configuration so the output would be roughly 22wpc.

 I also drive the Khorns with a 5wpc Pass designed mini ACA I built from a kit. 5 watts plays louder than I ever care to listen. 

  I've used plenty of SS amps over the years with various results.  The CJ MV-45 with just about any tube set I've tried wins every time. It's just a sweet almost lush sounding amp with three dimensional imaging. It doesn't give up any detail or dynamics to anything else I've tried. 

  I've never owned any McIntosh, I've only experienced it at friends places and in shops. I wouldn't pass up an opportunity to own some Mc gear though. I get the impression it is very reliable, which isn't really the reputation associated with CJ. I've been able to affect my own repairs on my amps over the many decades of ownership, so I'm not really complaining about reliability.

I took a look online and that The CJ MV-45 sure is purdy. Love the vintage vibes with it. I wish there was a way to hear all these amps easily. 

 

I've had a bunch of different McIntosh gear (mostly solid state) and can confirm it is fantastically reliable, well built and nice to gaze into those blue eyes. I can also say now with my MC225 experiment that there is a large difference in sound between what I have experimented with (MC-252, MA-352, MHA-150, C8) and the MC225. I feel lucky to have stumbled upon the reviews and taken a chance. I bet there is an old wise guy on this forum smiling and saying "finally the kids are figuring out what we have know for decades". I plead ignorance of the highest order.

[Marvel]

On 6/17/2024 at 3:09 PM, lighting guy said:

My favorite is still single ended, I'm a little partial in that regard.  In my opinion, the winner that day was a pair of Welbourne Moondogs (2A3 based SET), mainly for its 3D soundstage. 

I had a pair of Moondogs that I used on my La Scalas.  Simply magical, and I never should have sold them.

[blindman]

4 hours ago, Marvel said:

I had a pair of Moondogs that I used on my La Scalas.  Simply magical, and I never should have sold them.

 Marvel, I share your pain. 

 

I purchased, and built, the last pair of Moondogs that Welborne Labs sold before the collapse.

I, and everyone that I knew, absolutely fell in love with them on my Klipschorns!

But then, one day I needed funds to pay for a major surgery, so I had to sell them.

 

I thought that I had done my due diligence, and vetted a buyer (on this forum) who would be appreciative and take good care of them.

So I sold them for only what I paid for the kits and did not charge for my time or labor building them.

Much to my disappointment that buyer flipped them and I have lost track of where they are . . .

. . . although I keep my hopes up that I will be able to find them someday and buy them back.

 

By the way, I am "intimately familiar" with the pair that I built and should be able to recognize them easily.

And I have photos that I took during the building process that I can use for the sake of comparison (inside and out).

 

[Marvel]

I bought mine from someone on here, around 2004 and was the 4th owner. I doubt I'll come up with the money to buy mine back, even if the the possibility floated around. I've thought of building a pair of 2a3 amps from another designer, but life is short (shorter than longer, that's for sure).

[lighting guy]

The 2a3 seems to be a pretty special tube to design an amp around.  I recently put my Wright Mono 3.5s back in my system (replacing the 300b-based Wright Mono 7s I've been running for the last 10 or so years).  I'd forgotten how realistic and true the presentation is.  I had put them aside years ago in search of more bass, which I have now achieved by adding subs with my Cornwalls.  I think the 3.5s are back in for good.  

 

I once borrowed a 45-based home brew "Bugle circuit" amp.  The realism floored me, I owned Khorns at the time.  After a while though, I felt the sound was maybe a bit dry and clinical.  I wouldn't mind having another amp designed around that tube someday.  Especially now that I have subs to fill in the bottom end.