Mcintosh mc901 amp - no posts about this?

[Elftrader]

I'm taking a look at the Mc 901 dual mono amplifier and I came to this forum hoping to find lots of good info.

This is a combo solid state/tube amplifier and seems quite nice for by a well matched biamp configuration.

This model came out about three years ago, cost is about $38,000 and it's very big

Is this a successful amplifier and is it worth pursuing?

 

[TDX]

I would not. IMHO

 

[Digital Buddha]

i really enjoy mine in my system.

 

[Gregadd]

I started a thread. For some reason it never caught on.

 

[Another Johnson]

I'm taking a look at the Mc 901 dual mono amplifier and I came to this forum hoping to find lots of good info.

This is a combo solid state/tube amplifier and seems quite nice for by a well matched biamp configuration.

This model came out about three years ago, cost is about $38,000 and it's very big

Is this a successful amplifier and is it worth pursuing?

At that price point, there are many good options.
I listened to a pair driving top of the line McIntosh speakers (made by Sonus Faber according to The McIntosh Group’s rep Wil Kline. Also listened on a pair of high end Sonus Faber speakers.
The room was good. Sources were good. I was listening for fun, not to decide whether to buy them.
I thought the configurations I heard were musically engaging, enjoyable, noise and drama free, and well presented.
If I were in your position and was considering them, I’d spend some time (on a few days if possible) auditioning them at a dealer with a good set up.
Mcintosh, if nothing else, is reliably well built. It’s not exotic, but neither is it mediocre. Some folks hate them. My love/hate relationship with them has been all over the lot for 60 years. Make your own decision based on your own ears.

 

[Gregadd]

From it is an all in one soliition to bi- amping
if you like thezc sound it mayb for you.

 

[Elftrader]

Would it make sense to upgrade mcintosh 611 600 W mono blocks to the MC 901. All for the purpose of introducing tubes to the mid and Tweeter, and maybe improve sound coming from the bass drivers by cleaning up the signal since it is dedicated at that point.

Existing mc 611 monos I have into a B&w 802 D3 in a 14 x 20' room don't distort but maybe there will be a meaningful change to the mid/tweeters.

 

[Digital Buddha]

Would it make sense to upgrade mcintosh 611 600 W mono blocks to the MC 901. All for the purpose of introducing tubes to the mid and Tweeter, and maybe improve sound coming from the bass drivers by cleaning up the signal since it is dedicated at that point.

Existing mc 611 monos I have into a B&w 802 D3 in a 14 x 20' room don't distort but maybe there will be a meaningful change to the mid/tweeters.

I think it does but thats because thats what I did. the tube section on the 901s is fantastic and really does something special to the mids and highs over the Mac SS ive had. but you really need to audition it for yourself, I just think it's such a cool design, and sounds really really good.

 

[Elftrader]

I think it does but thats because thats what I did. the tube section on the 901s is fantastic and really does something special to the mids and highs over the Mac SS ive had. but you really need to audition it for yourself, I just think it's such a cool design, and sounds really really good.

Thank you. Nice to hear that about the MC 901.

The only other serious concern I have about it is the heat factor for all the tubes. How is this impacting you?

The room I'm using is 14 x 22 with 8 foot ceilings. In the summer it may turn it into a much hotter room despite AC.

It is a lot of tubes, 28. Also am considering the 1.25 solid state but that's a serious monetary outlay and not sure how mids and tweeters would benefit in the same spirit of what tubes would do.

 

[Elftrader]

How much heat does the MC 901 create? Have been told it's like a portable heater set to the low setting, which is horrifying.
That's a lot of heat being given off. Seems like a very uncomfortable amp to have in a room

 

[Another Johnson]

How much heat does the MC 901 create? Have been told it's like a portable heater set to the low setting, which is horrifying.
That's a lot of heat being given off. Seems like a very uncomfortable amp to have in a room

I’m sure it is. The tube section is similar in power to my LP275Ms, or my Ref 250 SEs. They typically draw about 300 Watts per amp at idle. I have to run the AC when the temp outside goes above 80F or the room is uncomfortable. My AC in that room is dedicated on its own unit with appropriate measures to keep it quiet. Nice in winter though.

 

[Another Johnson]

If I don’t run the AC, the temp creeps up to 80F at the amp end. I set the AC on 74F, and it runs intermittently.
I designed the room and HVAC with HVAC noise mitigation as a goal. It is quiet.
The room is very well insulated. 16’x34’ with 10’ ceiling. The supply and return lines are overhead away from the listening position. The unit is isolated and has a quiet distribution system. The room is on its own system and the set control is at the amp end.
The whole system draws about 1000 Watts in use with all tube and SS units running.

If you do not have good cooling capabilities, any big tube amps are going to be problematic for listener comfort.

 

[Gregadd]

Most big ss amps run hot.

 

[Another Johnson]

Most big ss amps run hot.

My KSA series Class A Krells were like space heaters too.

 

[Elftrader]

I am presently using Mcintosh 611 and they run cool. At Moderate hi volume, they only use 70 watts per mono.

The ref 250, 300 W monos have eight or nine kt150 tubes each, and these are rated at about 80 W each, they run very hot and audio research runs tubes aggressively. Mac uses 8 Kt 88 tubes in each 901 which are about 40 W. No idea how much energy used at idle. Mcintosh the company told me they have no interest in measuring Energy use by their amps and doesn't provide this info. Very very strange.

 

[Another Johnson]

I am presently using Mcintosh 611 and they run cool. At Moderate hi volume, they only use 70 watts per mono.

The ref 250, 300 W monos have eight or nine kt150 tubes each, and these are read it for about 80 W each, they run very hot and audio research tubes aggressively. Mac uses 8 Kt 88 tubes in each 901 which are about 40 W. No idea how much energy used at idle. Mcintosh the company has never measured it and can't provide this info. Very very strange.

My measurements at idle are my own. I’ve not seen CJ or ARC specs on this.
If someone is worried about heat generated, try smaller Class D.

 

[Elftrader]

I would buy a nice tube amplifier but if you want one with 300 W per channel it really heats up a room. It's absolutely horrifying and why people buy these unless the room is really really really large it's really crazy. You shouldn't have to run air conditioning every time you want to use an amplifier which many people I guess I do and many people have dedicated AC for their listening rooms which is just crazy.

 

[Another Johnson]

I would buy a nice tube amplifier but if you want one with 300 W per channel it really heats up a room. It's absolutely horrifying and why people buy these unless the room is really really really large it's really crazy. You shouldn't have to run air conditioning every time you want to use an amplifier which many people I guess I do and many people have dedicated AC for their listening rooms which is just crazy.

It’s not crazy … it’s crazy in your value system. You will seriously want to consider much cooler class D amps.

 

[Gregadd]

Except for class D almost all amplifiers are inefficient space heaters. Rate off dissipation is more important. I have seen wood stoves that are cool to the touch
In the northern part of the country many homes don't have a|c.
As for being crazy. Yes, this whole hobby is crazy. That's what makes it fun

 

[Another Johnson]

Consider that a pair of MC901s is priced at $38000. What’s another $5k to $10k for HVAC to keep the room comfortable if these are your bucket list amps?