ARC Ref 110 vs. Ref 210

I'm in the process of upgrading my system and need help with an amp decision. Current system includes ARC Ref 3 preamp, CD-7, Rega P5 turntable, and Dali MS-5 speakers. I auditioned the 110 at home, with pleasing results. We're designing a new home, where this system will live in a room that's approx. 20 x 25 ft, with 11 foot ceilings. Musical tastes are primarily jazz and pop/rock.

Given the cost difference and heat issues (I live in Texas), I would of course prefer to buy the 110. Still, I wonder if the 210 might be a better choice.

I would appreciate your expertise, particularly any advice from folks who are familiar with the MS-5's.

Always go with more power.
I faceed the same problem as you did. I eventually went with the Ref 110.

I talked to several ppl who heard both and they all seem to prefere the 110 by small marigin.

Here what one famous british reviewer wrote to me in an email:

"Big question, <----- 110 vs 210

If you want more slam and scale the 210 does it ultimately a bit better, at a cost!

The 110 is a bit more subtle, coherent and focused , partly because it is one box, common channel grounding, but less bass slam.

2x 210 will be hot, make no mistake, lots of standing power.

Hard choice !"

Personally, I have not heard them side by side, but a close friend of mine owns 210s, so I'm somehow familiar with them, and I think that the above statement is correct.

Hope this helps.
You have a relatively large room in your new house so 210 may be a better choice if you need more power to drive the speakers. If you have a smaller room then 110 would be a better choice. Happy listening!!
There is another great option which unfortunately doesn't work with your 4 ohm Dali speakers, but might be helpful to others with 8 ohm speaker systems. We have set up two of the REF110's in balanced bridged mode (also sometimes called push-pull). In this configuration your double the slew rate and cut the rise time in half while doubling power. You also retain the character of the REF110 amps.

A side benefit is that if one of your amps ever has a tube failure or is down for any reason, you have a second 110 that can run your whole system.
If you take the 110's, the day will surely come when you will want the extra slam and muscle of the 210's for a room that size. If you don't, you will always feel like something is missing. You've already got too much invested in other parts of your rig to not fully realize capability of your system.

Do it now (210's) and save yourself the time and aggravation of upgrading you surely will do if you buy the 110's.