I love this blog and was flattered Jeffrey asked me to write something. Few days ago I finished this 56 dc 171a headphone amp (more than 50% dht – 80 rectifier) – nothing fancy, scrap chassis, low cost.
Both my son and I thought it was OK at first - a bit flat. Today Jeffrey suggested to remove the 9ohm load resistors I had on the 5K:8 OPT's for the 32ohm headphones. I let my son have the first listen and in two notes he pronounces "It's Better!". It really came alive – open and fluid. Ten minutes later, thinking of Jeffrey, I treated my son to his first experience with Jimi...
Quad QA12/P Amplifier - This is pretty close to Quads first amplifier. I got to put my hands on one of these once very cool early British amplifiers. http://www.itishifi.com