A1 vs A1.5 vs M1.1

[goodsource]

can anybody help in characterizing the the spec, design and sonic differences between A1.5 vs M1.1
on paper both look identical, with M1.1 having a more powerful transformer (1800 vs 2200 VA) and may be a few more transistors at the output stage.
iam sure it would be more than that but can someone enlighten some facts with this.

just to add some more context like apartment living, 15A circuits only instead of 20A ,lower volume and power requirement kind of listening.
just to throw in some speakers , i have wilson sasha daw and may upgrade to wilson alexia 2.
in the above context will A1.5 perform similar to M1.1
also will two A1's in mono have better performance than a single M1.1
of course all these amps will be driven by a L1 linestage.
OR will two A1.5''s in mono have better performance than a single M1.1

let me also throw in here that i will not be adding one more M1.1 later . I am looking for what could be a optimal option to get into day one.also lets leave and not have pricing consideration as well in this context

iam hearing some opinion that in smaller spaces , two A1 in mono might be better as it could improve mids and highs and bass will manageable.
since i live in a apartment with a 15A circuit one A1.5 will be ideal for me if it has same finesse in clarity and articulation as an M1.1.
but if two A1's in mono if it can outperform one M1.1 then that will also be ideal for me because mono's reduce strain on the amplifier and speaker and as they have to drive only one channel
but if one M1.1 is a completely different animal light years ahead with A1.5 and in a different league of performance , then i will happily consider a single M1.1 in stereo mode.
or will A1.5 mono is a better strategy as they share same architecture and the red caps as M1.1.?
of course i have to do some listening in my room to come to a decision but before bringing one of these combination i wanted to get the views of CH owners and experts on this
looking forward to hearing your thoughts.

 

[vjayh]

I own both the M1.1s monoblocks and the A1.5s monoblocks and previously owned the A1s. My experience is that they all sound different and the circuit layout is different accounting at least in part for the different sonic presentations. The A1s were nice, but the A1.5s and M1.1s are a big step up. A1's didn't have enough current for my YG speakers.

The difference between the A1.5s and M1.1s is interesting. I suspect the preference between one or the other is very system dependent. The A1.5s have a more lively presentation; soundstage is closer, more immediate. The M1.1s have a deeper soundstage but a more laid back presentation. The M1.1 have more bass impact, I suspect due to more current and headroom, but the A1.5s are no slouch.

CH told me that the difference in presentation is due to the placement of the transformer in the circuit. Not a technical guy, but thought I'd pass that along. Anyway, most everyone else would say they preferred the M1.1s to the A1.5s, but at least in my system, I like the presentation of the A1.5s better. Like I said, a bit of it depends on preference and the rest of the system. I ended up with M1.1s on the bass, and A1.5s on the mid/ treble. That's how I'm currently set up. To me it was the best of both- Mid/ high of the A1.5 with the bass impact of the M1.1s. I have them on the YG Sonja XV speakers, which YGs can be very hard to drive. Wilsons are much easier to drive.

Hope that helps. Always difficult to know how they would perform for you but that's been my experience.

 

[goodsource]

thank you @vjayh .
thats interesting, so you are bi-amping wit 2 sets of mono's. nice.

 

[Jambo]

Nice Review of CH A1.5 by Roy G, which may help.

http://www.hifiplus.com/articles/ch-precision-a15-two-channel-power-amplifier/

 

[knghifi]

The A1s were nice, but the A1.5s and M1.1s are a big step up. A1's didn't have enough current for my YG speakers.

Is "big step up" mainly in current delivery and/or sound quality?

 

[vjayh]

In the case of the A1 to A1.5s, it was both a big step up in current and dynamics, but also sound quality.

 

[MadFloyd]

This thread is so fascinating to me. I have been dreaming of the M1.1 assuming that the different models were all similar in tonal balance and that the M1.1 was unquestionably the preferred model if you could afford it. But now I have to wonder if I’d prefer the A1.5 as I don’t want anything ‘soft’. Perhaps this softness is behind people who describe CH as tube-like?

 

[gian60]

My M1,not M 1.1,have the mid like tube but are not softness,but are shining and explosive with midhigh very open and transparent and very detailed
And ithink M1.1 is little more open than mine

I listen in shop and friend home D'Agostino,Mephisto,Soulution.Pass xs 300,Viva New Aurora,Boulder 2150,Spectral 500,ML 33,FM 711,Viola Bravo,all Kondo,but no one impressed me like M1

I think you can find good bargain mext months because some will sell to change with M10

 

[Elliot G.]

The M1.1 is a significant step up in sound performance over the M1and is the top in the line. I am assuming theM10 will take this to a new level however I have not seen it, heard it or experienced and probably wont till 2021 due to the time of its delivery and COVID.
We will be having a invitation only event at our showroom in Feb 21 to introduce the 10 series to our clients and invited guests where we will do on a one to one basis a direct comparison of the 1 series to the 10 series. This will be fun, educational and of course a musical event.
I do expect to have a few M1.1 traded in and this will be a great opportunity to get an M1.1 at a reduced price. CH is also going to have an option to send the amps back for recertification and will issue new warranty.

By the way a M1.1 is not dull, warm, rolled off or any of those terms. I have listened to a variety of amplifiers in my and my clients systems that are extremely well known and highly regarded and not once did any of those type of comments ever present themselves. In fact every single person that has put that amp in their system has bought it! Period!!
I personally can't wait to hear the M10 and L10 and I really hope it can take my time machine to a new place in the far away future
.

 

[Elliot G.]

oh one last thing the sound of an A 1.5 is right there with a M1 however the M1.1 is in a class by itself. IMHO of course

 

[MadFloyd]

So you don’t share the views of the person who posted their observations in post #2?

 

[Elliot G.]

So you don’t share the views of the person who posted their observations in post #2?

NO absolutely do not. The M1.1 is a better amp top to bottom and I don't think its close.

 

[JimmyS]

This thread is so fascinating to me. I have been dreaming of the M1.1 assuming that the different models were all similar in tonal balance and that the M1.1 was unquestionably the preferred model if you could afford it. But now I have to wonder if I’d prefer the A1.5 as I don’t want anything ‘soft’. Perhaps this softness is behind people who describe CH as tube-like?

I had a full CH setup in the basement to audition (M1.1, L1, C1) and “soft“ isn’t a word I’d use to describe the sound of the CH components.

BC (before Covid) I was ready to replace the my XA160.8’s with the M1.1, but now I’ll wait it out a bit.

 

[MadFloyd]

I had a full CH setup in the basement to audition (M1.1, L1, C1) and “soft“ isn’t a word I’d use to describe the sound of the CH components.

BC (before Covid) I was ready to replace the my XA160.8’s with the M1.1, but now I’ll wait it out a bit.

Hey Jimmy, good to hear from you. Given that I've owned XA160.8s (and know what they sound like) if you could describe the differences between the two amps it would be much appreciated as I'm considering the M1.1s.

 

[vjayh]

Both the A1.5 and the M1.1s are amazing amps; I'll avoid absolutes like this one is better than that one. Don't think I used the word soft, or other words that imply better or worse, but in my system the M1.1 are darker sounding in the midrange (compared to the A1.5s) but have more headroom and more bass impact with just limitless power reserve. Pretty easy to hear. Others may reach a different conclusion with different speakers/ different system.

My point as a long term owner of both with an ability to A/B pretty handily, is that they have a different sound, and while sometimes hard to do, you'd be well served before concluding to hear both in your system. The other variable with CH is configuration-- bi-amp, mono, bridge, etc, etc. It can be a little daunting, particularly with complex systems, but fun to experiment with different the configurations. There too sometimes the configuration you think will yield the best results may surprise you. Pretty awesome the amount of configurability of CH amps in recognition of all the different systems and variables.

 

[gian60]

I listened my M1 mono in the shop where i bought in comparison with Pass XS 300,
System was Esoteric Grandioso,transport and dac,Pass XS and XS 300 compared to L1 and M 1 mono
Speaker Rockport Cygnus

I prefer much more CH,more transparent,natural and fast than Pass XS serie

 

[MadFloyd]

I listened my M1 mono in the shop where i bought in comparison with Pass XS 300,
System was Esoteric Grandioso,transport and dac,Pass XS and XS 300 compared to L1 and M 1 mono
Speaker Rockport Cygnus

I prefer much more CH,more transparent,natural and fast than Pass XS serie

What kind of music do you listen to, Gianluigi?

 

[ashandger]

Hi Ian, in case of interest, Martin Colloms (HiFi Critic UK ) who just reviewed the Dart pre and power is due to review the L1/P1/A1.5 + X1s etc in the next issue of his mag which will probably be out mid December. Martin uses Magico S5 MKII. Martin is HUGELY experienced and previously reviewed the A1 as well.

 

[MadFloyd]

Hi Ian, in case of interest, Martin Colloms (HiFi Critic UK ) who just reviewed the Dart pre and power is due to review the L1/P1/A1.5 + X1s etc in the next issue of his mag which will probably be out mid December. Martin uses Magico S5 MKII. Martin is HUGELY experienced and previously reviewed the A1 as well.

Thanks, Ash, good to know.

 

[gian60]

I listen all kind of music,
Jazz,chamber music,pop,electronic,old rock