Audio Research Ref 110 vs. ARC HD220

I sell both and have spent quite a bit of time listening to them side by side with Quatros. My preference is for the REF110, especially on the Quatros where I like to run the REF on the 16 ohm taps. It has plenty of power for very loud listening in all but the largest rooms.

The HD220 is a very good amp but the REF110 is magic.

As an owner of a Reference 110, I would say that if you want the maximum tube “bloom”, musicality, and midrange presence, the REF110 will do a wonderful job, as long as your room is not too large and you do not need to play at extremely loud levels, for long periods. But to realize the full bass dynamics and speed of the Vandersteen 3a sigs, the HD220 can do do a better job. And you can play as loud as you want, for as long as you want, with no output tubes to replace. One other thing: if you often experience some line-voltage variation such as a dip of 8-10 volts or more, then I would also lean toward the HD220. Tube amps need consistent line voltage for both best performance and best service life from the output tubes.
I think, either amp will give you wonderful results, with slightly different sonic “shadings.”
Hope this helps you make your decision.

Tomer

It all depends on the size of your room and the efficiency of your speakers. In my 14x19 room, with Wilson Audio Sophia 2 speakers that are 86dB efficient, I have had absolutely no problems to rise the volume on my Ref 110 to the head banging levels.

Thanks for your input! I'll have to do a little more auditioning, but I think I'll listen a little more closely to the 110. How does using the 16 ohm taps change the sound/response of the speakers? I currently don't have that option with my current amplifier.

Using the 16 ohm taps on the REF110 with a speaker like the Vandersteen Quatro that has a pretty flat 8 ohm impedance, makes the sound bigger, more open, relaxed and effortless if a little less tight and fast. It's really a subjective preference and you should try it both ways.

Here's an imperfect but perhaps useful analogy.

If you are driving a car with a manual transmission on a road where the speed limit is 40mph, you might have a choice of two reasonable gears to cruise in, 3rd and 4th.

In 3rd gear (analogous to the 8 ohm tap) your RPM is higher and in the power region where if you step on the accelerator quickly the car will be very responsive. But if you continue to floor it you will wind out and red line sooner, not being able to achieve a very high top speed.

In 4th gear (analogous to the 16 ohm tap) your RPM is lower and may be barely at the beginning of the power band, so if you step on the accelerator the car will be a little less quick to respond, but if you continue to keep the pedal to the floor you will be able to achieve a much higher top speed before red line.

Hope that helps.