The PPA is ppl's Portable Amplifier. ppl has been building and advocating Jung multiloop type buffered headphone amp designs.
Uses National Semiconductor LM3876 Power IC. Voltage gain is 27dB.
200W audio amplifier solution using multiple LM336s and and design concept to reach even higher output power levels.
A commercial Class D Amplifier, complete schematics in pdf format.
This article is for those who wants to make their own car amplifier. In this article, I will discussed the car power amplifier in 3 steps : 1.The design of audio power amplifier, 2. The design of DC-DC converter, 3. Miscellenous tips for making car power amplifier.
The LM3886 is a high-performance audio power amplifier capable of delivering 68W of continuous average power to a 4Ohm load and 38W into 8Ohm with 0.1% THD+N from 20Hz-20kHz
Source: National Semiconductor Linear-Applications-Handbook. Vo = µ/2 = 500; µ = Yfs / Yos
Here is a little audio amplifier similar to what you might find in a small transistor radio.