The Magic of Tubes is Back with audioXpress May 2018 Glass Audio Special

The May edition of audioXpress continues to be a favorite among tube and audio electronics aficionados. For this Glass Audio Special issue, Menno van der Veen, details his fifth 300B-SE amplifier, Patrick Brunner discusses DIY Tube Amp Heat Management, and Gerhard Haas shares what he knows about output transformers for tube amplifiers. We interviewed Jason Stoddard, the heart and mind of Schiit Audio, and Richard Honeycutt compares Tubes, FET, and BJT circuits. Also in this edition, Andy Lewis looks at Back EMF in loudspeakers, and Ron Tipton finds a way to measure the high-frequency content of Master Quality Authenticated (MQA) recordings. Download your May issue now.

Recently, I got bitten by the nostalgia bug and picked up a pair of old factory-wired Dynaco ST70s in pretty nice condition. On one of the Dynaco ST70s, I installed a new 6GH8 driver board instead of dealing with the rare 7199 issue, and I designed a small (3” × 3”) PCB to combine the bias supply and added the LED bias-setting circuit. This article was originally published in audioXpress, April 2013.