Now, the only work left to do is decide whether these amps sound better through AR3a or Rectilinear Xa speakers (I have both, and will keep one set or the other). You all know AR. Rectilinear was a competitor back in 1970, and this model was a very lifelike speaker. Neither set has ever sounded better than with these Dynas.
My thanks to Bob and the others on this forum for their expert advice.