Aksa amplifiers driving Acoustat 2+2 speakers

Gram · « **on:** 20 Sep 2003, 01:59 am »

Interesting comments are being made about these amps. Can anyone advise whether they are suitable to drive Acoustat 2+2'S? Not a nice load...86 dbW efficiency, impedance dropping to around 2.5 ohms.. Your opinions would be appreciated. Thanks.

AKSA · « **Reply #1 on:** 20 Sep 2003, 04:16 am »

Gram,

If these are ribbons, then the 100W AKSA will handle them with aplomb.

If they are electrostatic, then no, they won't, sorry.

Cheers,

Hugh

Gram · « **Reply #2 on:** 20 Sep 2003, 05:56 am »

yes..they're electrostatics..Why won't they drive them Hugh..? Ive been using a ss 120W amp or a Radford STA-25 copy for years with them..

AKSA · « **Reply #3 on:** 20 Sep 2003, 07:11 am »

HI Gram,

Have a read of this:

http://www.audiocircle.com/index.php?topic=1816&highlight=esl63

It answers all the usual questions on ES speakers. The topic is quite complicated; ES speakers are a VERY difficult load for SS push pull amplifiers.

Cheers,

Hugh

Gram · « **Reply #4 on:** 21 Sep 2003, 11:34 am »

Thanks for that Hugh..damn... I'll wait for the hybrid. Any news of it yet..?

AKSA · « **Reply #5 on:** 21 Sep 2003, 12:10 pm »

Hi Gram,

Although almost fully built, it's on ice at present as I start making the retail version of the GK-1 and concentrate on design issues with Ben for the DAKSA.

Besides, I'm so bloody scared I'll fire it up only to find it doesn't meet expectations! It has a very trick sliding bias arrangement which is as yet untested, but should enable 44% efficiency with a potential single ended output of 42W per channel, allowing most real-world speakers.

I did make a 56W Single Ended amp once. It dissipated 620W of heat - I water cooled the beast - and I'll swear each watt was equivalent to about four watts of Class AB. The amp shook the ground like an earthquake; it was a revelation!

Thank you for your interest, I'm on the case!

Cheers,

Hugh