[AMRadio] Class AB and B audio XFMRS

doxemf at aol.com doxemf at aol.com
Mon Mar 13 20:07:02 EST 2006

Some of the early solidstate audio line anmplifiers and also power amps used a single ended circuit
cap coupled to the transformer to avoid DC in the primary. My 65 McCurdy console is single ended class a
cap coupled to the attenuator then about the same circuit cap coupled to mix buss with a quasi comp cap coupled transformer mix output. 20-20kc spec even with three transformers in line. 
 There are still some amplifiers using this technique and of course the heising mod varients.
 The C/L relationship of this type of circuit appears to neutralize some of the detrimental behavior of the transformers. I'm currently doing research regarding the relationship since the quality of the sound produced has a bit of the smoothness of Vac tubes without them. IE less fatiguing on the ears. The low freq response also has more of the fatness attributed to Vac tube amps.
Bill  KB3DKS/1

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