Audio Electronics: Myths in Tube Circuit Designs

Many audioXpress readers will be familiar with Peter Dieleman from his books on the theory and practice of tube amplifiers. In this article he debunks some of the myths, such as load (mis) match in output stages, which is by definition perceived as a bad thing, when that might not be necessarily the case. Another myth example regards the efficiency of a triode output stage versus a pentode.

The B&C Speakers DCX354 ring radiator coaxial dual-diaphragm compression driver is a similar design to its big brother, the B&C Speakers DCX464 that was featured in the October 2019 issue of Voice Coil. The DCX354 has a 3" midrange diaphragm and a 2" and is good down to 400Hz. The horn tested with the DCX354-16 was the new B&C ME464, a very large horn device made of durable polyurethane plastic with an 80°×60° nominal coverage pattern. This article was originally published in Voice Coil, May 2023.

In this issue. Mike Klasco looks at the exciting progress happening in magnets and new signal processing options for speaker design. James Croft compares patents of ducted loudspeaker designs for automotive. And for Test Bench, Vance Dickason characterizes the new Russo 44CDN-PK 1" PEEK diaphragm compression driver from SB Audience, and the B&C Speakers DCX354 ring radiator coaxial dual-diaphragm compression driver.

In this Glass Audio special issue, Menno van der Veen brings us his latest Vanderveen TRANS-PP80 Valve Amplifier, Tom Perazella remakes a famous (Z)OTL amplifier with 300Bs, and Peter Dieleman debunks recurring myths in tube circuit designs. Stuart Yaniger reviews the Hypex NCORE NCx500 amplifier module, while Burkhard Vogel expands his article on Vintage Op-Amp Noise Simulations, and Bruce E. Gillingham concludes its unique MB1 Monoblock Power Amplifier with Precision Bias Control.