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How to convert Class A/B amp to pure Class A

Hi. I own a wonderful Threshold Forte Model 3 solid-state amp. It is a Class A/B design that is rated at 200 wpc into 8 ohms. I have read that it is essentially the same amp as the Model 1A, which is a pure Class A amp rated @ 50 wpc, and that it is fairly easy to convert the 3A to the pure class A configuration (and consequently drop the power output to 50 wpc). I am fairly handy; anyone have any suggestions? I have read that constructing a brass or copper rectangular plate to connect the inner-most screw lugs of the 4 big caps is a good start. Any suggestions? Many thanks.
klipschking
elevick
2,636 posts
 
Wouldn't it make more sense to sell the amp and buy a class A amp? Tons of Thresholds, Sumos, Pass, Aragon and many more out there. You'll never get your money back out of this mod. And, that's if you are happy...
swampwalker's avatar
swampwalker
5,138 posts
 
When you say you are handy, does that include working around high voltages, soldering, using a VOM. etc. I don't think this is a simple as swapping out a couple of parts. I could be wrong. also be sure your physical set up can handle the high heat load. FWIW, the 50 watt Forte Class A amps were honeys, but I think you can probably buy one for $500> Of course your "newly modded" one would presumably have all new caps which at the age of the Fortes are likely to require replacement on any used one you would buy.
unsound
7,311 posts
 
You might get more help on: diyaudio.com
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