The CMoy is an inexpensive, compact, and easy-to-build headphone amplifier that nonetheless packs some serious power and audio quality. It’s a great first project for fledgling DIYers and it no doubt is an improvement over the stock headphone amp of most consumer audio interfaces. The CMoy is also handy for portable recording, as it runs on a 9v battery.

Notable Features:

• Fits in an Altoid tin
• Compatible Opamps:
• OPA2132PA
• OPA2132P
• OPA2134PA
• Many more…
• Can run on batteries or a dedicated power supply
• Low voltages and ample documentation make this a good beginner’s project

Price: Approx $30-$200 depending on parts
More Information:

• Tangent’s phenomenal CMoy tutorial. Start here!
• A review comparing the CMoy to the $350 Grado RA1