[luvmusik]

Stax SRM-1/Mk-2 Professional A-B-C versions of amplifier (with both pro bias 580v & normal bias 230v outs).
 
What differs between versions A-B-C ?
Is any difference audible ?
What years were versions made ?
Are versions common or rare ?
Parts any better in versions ?
Parts available for different versions ?
Any version known for better longevity ?
Were all versions black or silver color ?
Is there a preference for any version ?
Any other details betweeen versions ?
Can it drive Koss ESP950 with enough oomph (with adaptor cable) ?
Will it drive every model Lambda & Airbow well, or falls short matching on some models (for it's price) ?
Any pros or cons ?
Does it differ or is the same as the SRA-14s amplifier section, & is it quieter ?
What does lacking an extra intermediate stage amplifier (vs SRA) result in - pros & cons ?
Can it greatly outperform a Woo Wee/hi-end speaker amp combo generally & listening impressions for sonics ?
Is the frequency bandwidth more linear, balanced and better controlled of extremes in volume-frequencies-voltage swings compared to Woo Wee (amp vs transformer question) ?
Published low frequency down to DC, are there any measurements supporting it's bottom limit (18,16,14,12 Hz, etc) ?
Pros & cons vs SRM-323 or SRM-313, and listening impressions for sonics ?
Any other important points, as I am trying to learn more about this amp ?
Appreciate everyone's input.
 
 
 
 
 
 
 

 

[luvmusik]

Hoping for info.

 

[edstrelow]

I have had all three although I foolishly sold my C model. I can' t hear any difference between my gold A and black B. They also ran  my old ESP 950 fine.  I believe part of their advantage is that they have greater peak voltage than many later  Stax amps,  about 360  volts if I remember, vs 300 for my transistor    SRM 3 and many of the tube amps. The A's are the oldest. Some people recommend replacing capacitors. I have not done so and can' t say they are that much different from the 717 I bought new. Still, that may depend on just how much they were used and abused.

 

[luvmusik]

Thank You, I always greatly value your advice.
 
Have you had a chance to hear it vs any of the SRA integrated amps ?
 
Super information, much appreciated.