This method of deriving the center (third) channel of a stereo system is an exclusive Dynaco development which provides the proper in-phase (A+B) signal without loss of stereo separation and without the need for an additional amplifier. It is useful where the left and right speakers must be widely separated, and it also enables the use of the third channel speaker as a monophonic system in another location.
Doesn't look like the circuit will work in an ST-120 as designed using my 8ohm speakers, due to the lack of 16 ohm taps for output.
UPDATE > > See Post #13 ... apparently the ST-120 DOES have 16 ohm taps, and Bob gives a step by step on how to make it happen.
Credit where credit's due ... here's the PDF I pulled it from ...
Last edited by sKiZo on Sun Aug 25, 2013 5:13 pm; edited 1 time in total