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suggestion for a SS class AB amp that sounds like a class A ... if such a thing exists

Looking for an amplifier below 2K for my Altec 620A (99 db efficiency). My actual amp is a Sugden A25B, which has 34 watts/chanel in class AB. Although quite musical, it lacks transparency and details. Of course, the best amplifier would be tube or class A but I'm trying to avoid these because of the heat and the electricity bill (my amp is on all day long). My short list include :

  • Audio by Van Alstine Set-120
  • Ayre AX 7e (used)
  • Sugden Mystro (class AB)
  • Benchmark AHB2 (used)

NOTE : please, no class D since I'm not familiar with it (and pretty skeptic too).
128x128alaindexe
georgehifi's avatar
georgehifi
10,312 posts
 
a SS class AB amp that sounds like a class A
This thread is going nowhere. As it doesn’t address the OP’s thread title

Nothing repeat nothing! solid state A/B (low bias A) sounds like a 20w> high bias Class-A amp.
As there is no xover distortion in Class-A when the top and bottom transistors switch over from each other, because they’re still both biased into Class-A.
The transistor xover distortion is most noticeable in the highs, (strings, piano, tops of female high notes etc) on a low bias Class-A/B amp when it switches to B, after a couple of watts.

You need around 20w of Class-A to make it disappear on a A/B amp, then it gets too hot because of the rail voltage to get it to be 100w in Class-B. The A’s heat goes up exponentially. compared to just having a 20w class-A push pull with no Class-B

So go back to my first post, bi-amp with a simple 20w Class-A for the highs (no B and not very hot). Then an A/B for the bass.
https://forum.audiogon.com/posts/2065044

PS: last weekend we listened to Wilson Alexia MkII’s driven by a Class-A/B Gryphon Antillion Evo (it’s got 3 Class-A bias settings 10w 30w and 100w, switchable on the fly), we were listening mainly to streaming v cd, and at the end of the session we decided to go from 30w to 100w, all of us heard the improvement within seconds, and felt the room heat up after 1/2hr. (Didn’t change the streaming v cd outcome though).

Cheers George
jafant's avatar
jafant
19,742 posts
 
alaindexe

Another +vote for AYRE.  Happy Listening!
alaindexe's avatar
alaindexe OP
75 posts
 
Thank you all for your suggestions ... they are greatly appreciated ... I am researching each of them and added to my list the Belles Aria, Plinius 8100, Portal Panache and Odyssey khartago ... Apart from the Belle Aria, all have 100 watts / channel (or more) ... as my speakers are 100 db efficient, I won't use all that power ... my current amp is 34 watts / channel and it can drive my Altec hard enough ... I'd rather have a great sounding amplifier of 50 watts (plus or less 10 watts) than a 100 watts (or more) ... thanks!
audio2design
1,351 posts
 
The Benchmark distortion at low power, i.e. where crossover distortion comes into play is every bit as good and probably better than most Class-A. Same would be true of several new Class D amps.


Nothing repeat nothing! solid state A/B (low bias A) sounds like a 20w> high bias Class-A amp.
As there is no xover distortion in Class-A when the top and bottom transistors switch over from each other, because they’re still both biased into Class-A.



techno__dude
511 posts
 
Luxman M-900u is tha best. 150 W. RMS Will make any PassLabs class A amp sound broken...

First 12 Watts high bias class A. With most speakers, you never get out of the class A range.
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