and now for something completely different part 3

[JoaMat]

Finished the right channel today. Feedback as suggested by Justin. Bias servo as suggested by Kevin.

Red smoke – Super Symmetrical mode.

Green smoke  –  Zero Feedback mode.

[rumina]

i habe some current mirror amplifier ss/zf version 1.21 here that i like to use for the amp build.

may i ask about two points on the underside of the board (orange marked) look liks place for a jumper on the front siede the are between the two 82ohm resistors. are they for jumper and/or what are they used for. thx

[ang728]

reserved for the SMD MLCC 47uF Caps

I used Thru-hole ones

[rumina]

thank ang728 for the info, then im ready to order parts 🙂

[rumina]

finished my cfa3 this week, thanks kevin gilmore for the desing and the support from the forum members.

running on +-30v with moderat bias, changed the gain resistors to 3.2k for lower gain.

needed some 3d printed parts so that all fit fine, a cfa3 in a quad 405 chase. no pot this time, i use a dac with volume control or a preamp.

after all amps i build i think the best solution for a 1 case build ist mounting the trafos outside in vertical position, absolut no magnetic hum inducted. i also added grain oriented metal band around the trafos inside the trafo cases.