Wednesday, November 26, 2008

Starving Student Headphone Amplifier

Today I finished a Starving Student headphone amplifier as designed by Pete Millet. It is a hybrid design using 19J6 tubes and a low-z mosfet output. I did double the output coupling capacitor to 300uF (three 100uF capacitors in parallel) and increase the power supply capacitance a bit to 220uF. I mostly stuck to pedestrian parts - the only specialty capacitors I used were .1uF/63V ERO Polycarbonate coupling capacitors, a few 220k KOA resistors and AB carbon composition for the gate of the output mosfet.

I won't bother to show off the insides since it is nothing but quick n' dirty spaghetti wiring!

How does it sound? Very good. Using Sennheiser HD-570 headphones I hear no obvious distortion or coloration. Nice bass control, great mids and tons of details I don't hear using my speakers. For an overall budget of under $80 it is a good project - for electronic beginner and experienced alike.