Op amps and Pass Transistors

[Chris Daly]

I have been doing some interesting discovery on the sound of op amps with and with out pass transistors.

See my blog site: opamp - opamp construction

Surface mount soldering skills are needed. I use a x12 magnifying LED lamp,and vice with pivot adjustment.Either enamel wire or just 1 strand of RG58 coax the silver colored wire is used between the bias resistor and the base.

With pass transistors BC846 NPN and BC856 PNP installed on the Brown Dog dip adapter in a emitter follower configuration the left and right stereo balance improves immensely. To a level of degree making conventional op amps a complete waste of time.

Both positive and negative rails are catered for. The bias is set at 6.5ma this seems to sound the best.

Happy listening.
Cheers / Chris