Thoughts on Audio Research D70

As Hifigeek notes, the circuit is almost identical to the D-115 but with 4 output tubes instead of 8. This is a really nice tube amp, along with the D-115 and for the price of purchase on the used market, if in the market for a tube amp, you can't do better at the price, at least I haven't heard it. With improved caps and careful selection of input/driver tubes these amps can really compete if lacking the ultimate detail, air and bass control of much more expensive tube amplifiers. The build quality is superb as ARC is noted for. You can't lose, the prices used on these amps are higher now than 15 years ago indicating their continued value.

Indeed the D-115 Mk 2, which I owned for several years and is currently used by a friend in his system, has great bass drive and slam and is very dynamic HOWEVER it has less control and definition in the low bass than my current amp or some others I have listened to in my system. Also the presentation is a bit less airy, missing some of the ambient detail of some more resolving amplifiers. The D70 and D115 fall into the general category of "classic tube sound", a little rounder on the leading edges and thus can sound a bit fuller AGAIN a preference issue as often is the case in these matters. When more resolution is gained poorer recordings can come off as harsher than with a somewhat more forgiving amp. To be honest I could easily live with his amp as he has owned it for 12 years and done quite a bit to enhance its performance, again a great choice but still not as ultimately resolving as some that I've had in my system (all OTL's btw) but not enough of an issue to fret over for sure. Preferences and taste always comes more into play than absolutes but on balance these are truly excellent products and have aged quite well.