Circuit Project Electronic

care must be taken to ensure that R5 and RV2 are adequately rated. The current through these components is slightly greater than the sum of the output transistor base currents. The output transistor base current is the output transistor quiescent collector current (Ic) divided by the current gain (Hfe) of the device. The current through [...]

A high-current output amplifier for low-impedance dynamic headphones such as the Grados. The amplifier features an new servo biasing circuit which operates entirely outside the audio feedback loop. The author includes a balanced-bridge version of the amp for headphones that are wired in dual-mono as well as instructions for converting a Grado SR80 to dual-mono [...]

I was in need of high quality headphones amplifier because of many reasons and decided to build SDS Labs phone amp. This is extremely rewarding project in a sense that it is fully documented, includes PCB, parts list and building notes - so it’s easy to build and then it sounds great. I have used [...]