A Double-Ended Two-Channel Amp

Following the publication of its original SE 6C33C amplifier in audioXpress July 2004, Ari Polisois returned with more information on how to further simplify the whole construction and reduce the costs. The results, as the author describes, "combine the advantage(s) of the push-pull (mainly power) to the wonderful character of the SE: sensitivity, smoothness, simplicity, and warmth (due to the 2nd harmonic content, easily tolerated by our ears, as against the third, fifth, seventh, and so on harmonics produced by the push-pull)." This article was originally published in audioXpress, February 2008.

This article from respected author Ari Polisois deals with a single-ended amplifier with enough power to drive even the most difficult speaker systems - delivering 50W per channel. This is a project that quickly became the focus in lots of tube-oriented forums and has inspired long threads and many iterations, including further articles published in audioXpress from the author himself. This article was published in audioXpress, July 2004.

Where do tubes come from? In this article Richard Honeycutt revisits the history of tube electronics, from its early invention to the widespread adoption in radios and television receivers. And because familiarity simplifies tube selection, the article explains where some of the most common tube types can be applied in todays designs on power amplifiers and pre-amplifiers and tube stages. This article was originally published in audioXpress, April 2013 as part of the Hollow-State Electronics monthly column by Richard Honeycutt.

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.

In this article, Richard Honeycutt provides a brief description of the main tube types used in audio applications, from triodes to tetrodes and pentodes, describing its uses, features and potential benefits. If you are looking for a quick reference reading about tubes that have been used in audio amplification this article is a great start. This article was originally published in audioXpress, May 2013 as part of the Hollow-State Electronics monthly column by Richard Honeycutt.

Now launched on crowdfunding platform Indiegogo, the PLASMA Pedal is an interesting innovation in an area where there's hardly been any for decades. The idea for the PLASMA comes from a young Latvian company, Gamechanger Audio, dedicated to infuse new ideas into the musician market. And the PLASMA is certainly new in the fact that instead of the traditional circuits, it sends continuous high-voltage discharges within a xenon-filled tube. In essence - playing a bolt of electricity!

Reedsburg, Wisconsin-based Sound Devices announced the recent acquisition of Audio Limited, the UK manufacturer and developer of high-performance wireless microphone systems. Audio Ltd., now a wholly-owned subsidiary of Sound Devices, will continue to operate out of its Watford, UK offices with Kishore Patel and Lee Stone continuing as managing director and technical director, respectively.

audioXpress February 2018 explores the progress being made by ORA Sound and GraphAudio, two pioneering companies with distinctly different approaches to the use of graphene based transducers. We explain why open reel analog tapes are coming back in force, the differences between Line Source and Point Source speakers, and how Dante Domain Manager is providing an integrated approach to media network management. All this and much more, now available!

This year we thought our readers would like to know which of the topics and stories published online in 2017 were the most popular for our community. We looked at the most-read articles of 2017 in audioXpress.com (which also includes selected articles from Voice Coil magazine), and we created this Top 10 list of news stories and online articles. Here are the results!

The MA252 Integrated Amplifier is the first ever hybrid integrated amplifier design from McIntosh. Unveiled early November 2017, the MA252 is now shipping. The amp brings the benefits of vacuum tube (valve) to its preamp stage, with solid-state technology on the output stage, all with a visually stunning, integrated package, taking retro design cues from the legendary McIntosh MC275 Vacuum Tube Amplifier.