The MINT Headphone Amplifier

What is a MINT?

The MINT was a Jung multiloop type amp circuit designed similarly to the META42 ® but packed down into a much smaller board. (About two fifths the board area!) The cost of being small is that the MINT wasn't expandable in any real sense, and was harder to build than some bigger amps.

The MINT is now obsolete. I have replaced it with the PINT design.

The MINT board featured:

Very small board size: 1.9" × 1.5" (48mm × 38mm)
Accepts dual-channel SO-8 op-amps.
Burr-Brown BUF634U (SO-8) buffer on each output channel, including a place on the board for a bandwidth setting resistor.
Very basic power supply circuit compared to META42: just two 10mm diameter electrolytic capacitors and an unbuffered TLE2426 rail splitter.
Reverse power supply voltage protection (crowbar method)
The board makes using 2× series power sources easy. This is ideal for 2×9V batteries or 2×AAA battery holders.
Accepts CRDs for biasing the op-amp channels into class A.
Pads for the Panasonic EVJ potentiometer
Most resistors are on 0.100" × 0.300" spacing so you can put a DIP socket in their place and socket the resistors for easy experimentation.
You can cut the board in half down the long axis and connect the halves together back-to-back. This allows you to mount the board in the case with the Panasonic pot sideways, which is a must for short enclosures like mint tins and Serpac H-65s. (Picture)