Monostrapped Atma-sphere M-60


Well made a ton of changes to my system.
Fell into Atma-sphere great buys.  Waiting to get my M-60’s. Just wondering if down the road I got different speakers like Maggie’s or Higher End Vandersteens. Instead of buying a different Amp if it would make sense to Monostrap the M-60’s. Wondering if anyone had had experience doing this.
My system is as follows.
Quicksilver M-60 ( Replaced most likely by the Atma-sphere.
Atma-sphere point to point UV-1 updated with Vcaps. Next Power Regulation at the end of the month.
Bel Canto Dac 3 
Vandersteen 2ce Sig ii


128x128Ag insider logo xs@2xpstores
Ralph should weigh in but our room and how loud you listen may impact perfromance w your current speakers - while a relatively easy load they take some grunt to extract the most out of the acoustic coupler....you may find an Anticable autoformer necessary....

the Treo CT is quite. lovely IMO and would reward the transparency inherent in Atma designs....

have fun and enjoy the music...
+1 Tomic,
I own the Treo's and use a pair of MA-1 with MP-3. It is one of the most natural pairings I can think of ( I also own a pair of Ayre MX-R's). Both have me enthralled. I really can't think I need to change or upgrade (even though the MX-R's can be upgraded to Twenty status).
Like Tomic said, Ralph would be the best to answer, but I suspect the M-60's should be able to power a pair of Vandy 2's with no problem. If you got a pair of 2wq subs, I think it would be a slam dunk, as the amp has only the top end to power.
Should Ralph think the autoformers would be a good addition, I have a set gathering dust that you could try. I always wanted to put them in, but things sound so good...
Bob
I know the 2ce sig ii can easily be powered and will sound great with the Vandies. I guess my question is...... If I went with a harder to drive speaker. Has anyone monostrapped the M-60 to drive such speaker. Could just go with the MA-1 down the road. But could be fun to play with a set of four M-60’s.  My guess is no one has tried this but Ralph. I’ll be talking to him soon. Just have bugged him enough. Thought I’d ask here if anyone has monostrapped the M60 or even the MA-1. Am guessing no reason to Monostrap them. 
@pstores, perhaps I’m not understanding something, but Atma-Sphere M-60’s are mono amps. How can they be "monostrapped"?
Oh, I got it now.
In my opinion, I don't think you can do it as there in no 'bridge out/in'
on the Atma's. I guess the only person who could know of a way to accomplish this would be Ralph.
Though when he finally gets his Class D amp ready, I bet he might make them bridge-able.
If you do think about upgrading speakers, I know Ralph recommends Sound Lab as the most reliable and easy to drive electrostatic, and they work well with his amps.
If you go with Maggie's you could add a pair of Zero Autoformers to help with impedance issues.
Lastly, if you get the Vandy subs, the crossover will relieve the amp of demanding lower frequencies. You might just be able to run the Treo's with the MA-60's.
Bob
Based on the video I don't think the M-60s are set up for such operation unless they are modified and only Ralph will be able to say if that is possible. Why not get 4 x M-60 and biamp instead (although it could be helpful to get a pair of Speltz autoformers for the amp powering the low end)? Since I've gone to biamping I can tell you I'm not going back. FWIW I have used a pair of M-60s along with a solid state amp and an electronic crossover in a biamp arrangement with Quad ESL speakers and the sound was awesome.
The M-60s or any of our amps are easily monostrapped. Many years ago the idea of making only one amplifier and you just got more if you needed more power did occur to us. But the market seemed a lot happier with different models.

You need a 'Y' adapter to parallel the inputs, and some jumpers to parallel the outputs. The resulting output power is slightly less then 3X the original 8 ohm power (60 watts) of a single set of M-60s.

The output parallel connection must be broken in order to set the DC Offset correctly.

Just my opinion of course but I really don't think its a good idea to make **any** amplifier work hard for a living! You just make more distortion. In this regard 8 ohm speakers (all other things being equal) will always sound better than 4 ohm speakers and 16 ohm speakers (all other things being equal) will always sound better than 8 ohm speakers. But all things are never equal...

Happy Holidays everyone!

mostly joking...but 4 x M-60 would be a tube salemans dream !!!! perhaps only exceeded by a REF-750

enjoy our stange hobby !

jim
Jim,
   You could always Monostrap the biggest set of Atma-spheres..... Lol... My guess is the amplifiers would work less. And be easier on tubes. Be interesting to see what it’s like. 3x Power is huge. I was think it would only be 50% increase maybe double. Wow, they would just purr along.....  considering average listening levels they’d never see anything but light use. Maybe after I recover from my purchases as of late I will look at this more closely.
   Thanks Ralph for your input. I did read in several places that these were easily Monostrapped.  Good info.... 
  Bob thanks for the input also. I’ll look at the speakers. Still will need some recovery time. But next year I’ll be looking to do that upgrade. 
I have a 600 WPc “ mini-me “ Monoblock right next to Darth, see my Poverty Bay system photos...they don’t call it Poverty Bay for nothing !!!!!

@tomic601 ,
Wow, those 7's are close together. How large is the room?
You also seem to like water views.
Bob
@gdnrbob. They are now just about 8’ tweeter to tweeter...the pictures are of older tighter setup, they are another foot out into room, front of cabinet is now 37” from rear wall... I keep tweaking it. The wall they are on is almost 16’ but very high ceiling with many irregular openings...

water is life... for me anyway
music is frosting 
But before anybody draws the wrong conclusions... the 200 WPC Ayre VX-R was plenty of power for my listening habits/room

i even had a loaner aRC REF 75SE in the system while Ayre was back at Factory- adequate except for Cowboy Junkies - Devils Paintbrush Road....

try that out.....
In addition to more power, a potential advantage of monostrapping (i.e., paralleling) Ralph's amps is that the resulting output impedance would be cut in half.  In the case of the M-60 Mk 3.3 for example, the output impedance of a monostrapped pair would be 2.05 ohms instead of the 4.1 ohms that is specified for a single monoblock.  That would seem likely to significantly broaden the range of speakers that would be suitable matches for it, and potentially eliminate the need to use a Zero autoformer in conjunction with many speakers.

Regards,
-- Al
Al,
   That was exactly the information I was looking for. I was going to ask Ralph about that. Ummmmm.... Thanks  for the response.