Art Audio Carissa Signature 845 or 300 b amp?

08-14-12: Mattzack2
I have Dali Helicon 800 speakers at about 90 db. No problem with the 845 at 16wpc. I need to sell my Carissa and get serious about a nice 300b amp.

The MkII version of the Helicon 800 is specified as 89.5 db for a 2.83 volt input at 1 meter, with a 4 ohm nominal impedance. A point to keep in mind is that that means its efficiency is 3 db less (86.5 db) for a 1 watt input. That is because although 2.83 volts into 8 ohms corresponds to 1 watt, it corresponds to 2 watts into 4 ohms.

That assumes particular relevance with a tube amp, which will not increase its power capability significantly into low impedances, as a solid state amp would.

Also, if you may be interested in a higher powered push-pull 300B amp, rather than a low power SET amp, you may wish to consider the VAC Renaissance series (the 30/30 or 70/70 models, which are in your price range). Research posts by member "Raquel" for lots of good information about them.

Good luck in your search. Regards,
-- Al

A P.S. to my previous post. Keep in mind also that many SET amps will not do well into a 4 ohm load, even apart from power capability/speaker efficiency considerations. The Franks, for instance, appear to only provide 8 ohm and 16 ohm output taps (Charles, correct me if I'm wrong).

My push-pull-parallel VAC Renaissance 70/70 MkIII, btw, has taps designated as "4 to 8 ohms," "2 to 4 ohms," and "1 to 2 ohms"!

Regards,
-- Al