A "best amp for Ohm Walsh Tall 1000's" question with a twist...

Hey all -

I'm a long time reader, mostly lurker.  I've dipped my toe in the audio hobby over the last couple of years, and Audiogon has been my education.  Many thanks to all for contributing your thoughts here!

I am considering a power amp upgrade.  My current rig is digital source -> microRendu -> Metrum Musette -> Quicksilver line stage -> Rotel RB-980BX -> Ohm Walsh Tall 1000's.  At some point I plan to upgrade the Musette to an Amethyst - the Musette seems thin, to me.

My wife and I listen to all kinds of stuff, mostly acoustic and choral.  We (er, I) listen to some stuff loud-ish, but we don't really "rawk out".  What we value in sound are naturalness, realism, presence, and musicality.  I like to hear everything that's going on - I don't need acid-etched definition, but I also don't want a big warm cloud of sound.  And I like sound with a bit of weight - not loud, but present.

I'm pretty happy with most of my gear.  The Rotel is getting it done as far as getting a baseline of power to the OW's, but I suspect I could do better.

The twist in all of is that it would be really, really, really good if the amp could fit in our existing stereo cabinet.  Like, "v7b9b13 isn't banished to the couch" good.  Which means it has to fit into a space about 18" wide, 13.5" deep, and about 7 or 8 inches high.  I have some flexibility in the vertical dimension, but not in width or depth.  The 13.5" depth has to account for connectors and wires, so we're really talking about more like 12".

For reference, the Rotel fits, just.

I've been considering vintage Mac for this - MC 754 or MC 2100 - because my understanding is that the Macs have the beef - the current - to drive the Ohms nicely, and because both of those amps will fit in my little shoebox of a space.  I'm looking for all y'alls input on a couple of things:

* any other contenders worth looking at?
* any reason to run away from either (or both) of the Macs as fast as I can?

I generally understand the whole autoformer / no autoformer thing - generally - but any thoughts about the appropriateness of that aspect of the two amps in the context of my rig will be greatly appreciated.

Many thanks in advance for your thoughts!!

All the best 
Ag insider logo xs@2xv7b9b13
I should add that I have also tried a Schiit Vidar as the power amp.  A very nice, very capable amp, fits in the required space, but it didn't seem to really wake the OW's up, if that makes sense.

It seemed cleaner than the Rotel, but the Rotel seems to engage the speaker more.  The result is not necessarily louder, but is fuller and rounder, more present.  To my ear.

In case that's helpful.
If you can find one in good repair for a reasonable price, the Mac 2100 will have all of the sound attributes that you want, but you do need to be concerned about the cable connectors because back when it was made everyone was using lamp wire. There are adaptors that work well on ebay.
Changing to the Mac 2100 from the Rotel is a step backward IMO! The Rotel is a far better and advanced amplifier! 
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But if you still want to change then I recommend a First Watt F5. Class A with enough current to easily drive the Ohms.I have one - and Ohm Sound Cylinders.

How big is your listening room, and how loud is loud? I wouldn't change the amp just to change it, if you like what it does. Does it seem to be straining/clipping at the levels you listen to? Only you can be the judge.

Otherwise, look at the usual small case subjects, class D from Bel Canto etc. There are quite a few small form factor amplifiers out there that will get the job done, as long as you don't have bias on class D in general.

Another non-audiophool amp that I found to be good with Ohm is the Anthem PVA series, and would fit the bill size wise too, and quite frankly, I thought it sounded rather good. Don't get sucked into the A/V amp thing.

Just my quick 2-cents worth! 

I’ve not heard any of your gear, but on paper, that amp appears to be a good match.

The OHMs like power and current, but if you are not looking to go louder and clearer, that may not matter.

Class D amps (most efficient) will likely produce a noticeable change in the sound in the direction you are looking, and keep product size minimal, so if you must try something else, I would look at well received Class D amps with good current delivery capability regardless of actual power rating. PS Audio is a popular brand here that has some interesting new offerings in this area though I have not heard. Read some of the recent Class D threads here for more ideas perhaps.

Also hard to go wrong with Bel Canto. I use BC c5i integrated with my similar size OHM Walsh speakers in a second system , and Bel Canto ref1000m monoblocks with my big OHM F5s (12" drivers) in my main setup.

You often will not realize how loud the music actually is with these amps, much like with good quality tube amps. It’s a good thing in that the music sounds fuller and more completely flushed out without sounding loud or fatiguing as is the case with many lesser amps.

But with Class D , unlike most tube amps, you can drive most any speaker including the OHMs to their maximum without ever breaking a sweat.....very effortless sound from the smallest box possible   due to the efficiency of Class D.

At least that is the case with the Bel Cantos. Also Class D amps tend to soft clip as well if/when they are being maxed out, another way that they work and sound more like a tube amp than most Class A/B SS amps.

I was always against class D  but I have recently heard  Bel Canto drive Maggies , they are good, very good .
Thanks for your comments here, everyone.

I hadn't considered the Class D's because they are "supposed to be" less musical than A's or A/B's.  Q Audio in Cambridge carries Anthem, so maybe I will stop in and take a listen.

I think what I am most likely to do is to first swap the Musette for an Amethyst, which is something I definitely know I want to do, and see what the system sounds like before changing anything else.  I'm also running Mullards in the Quicksilver right now, and will swap those out for Valvos I have, that I have used before and know that I like better.

Do those things, that I know I want to do anyway, and see what it all sounds like.  Then proceed from there.

Many many thanks for your comments, they are enlightening and much appreciated.