audioXpress May 2021 Celebrates Its Glass Audio and Audio Electronics Roots

Our May 2021 Glass Audio Special edition is certain to inform and inspire you. We reveal what is happening at Western Electric's new Rossville Works in Georgia, where production of 300B tubes is ongoing, we explain how to draw tube load lines, and we offer a valuable preamplifier design that enables you to compare the sound of tube and solid-state circuits from the same audio source. There's also a versatile stereo tube amplifier design to build, and plenty more audio electronics theory and practice in this edition. Now available online and in print.

A brand new series of tubes was launched and the first model is now ready to ship worldwide! The new 6L6GCM-STR is the first model from a new high quality premium tube series named REBASE, from Tube Amp Doctor (TAD). As the German company explains, the 6L6GCM-STR REDBASE is an entirely new TAD development, recommended for lively clean sounds as well as powerful broadband multi-channel amps, an ideal upgrade for any guitar or high-end amplifier that uses 6L6GC or 5881 tubes.

The April 2020 edition of audioXpress is now available and features two essential Market Updates, one focusing on the industry transition to active headphone and earphone designs, and another on how to leverage the latest voice capture and processing technologies. The issue also explains how to evaluate listening effort, and Stuart Yaniger puts the Linear Audio Autoranger Mk II Interface to the test, while Ed Simon writes about AC Power Rectification. Another issue to read and use as reference.

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.

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.

Here’s an amp project especially for first-time builders featuring the 6BQ5 tube. As Rick Spencer writes in its introduction, "In order for this beloved hobby of ours to thrive and survive well into the future, we must always strive to make it interesting to newcomers." With this in mind, Rick Spencer created this single-ended design using the 6BQ5/EL84 tube in triode mode. This article was originally published in audioXpress, October 2008.

"There is nothing quite like a quality tube amplifier," states the author in the introduction to this directly heated triode amplifier project. The idea for the amplifier started from the author's discovery of the Loftin-White circuit. The author chose the 2A3 directly heated triode power tube to implement the Loftin-White circuit. The 2A3 vacuum tube is a power triode capable of outputting 3.5 W in a single-ended Class A configuration. This article was originally published in audioXpress, August 2013.

When this great tube amp project was published originally in Glass Audio magazine, Ed Dell wrote “Joseph Norwood Still is pushing the envelope. His most recent triode design, which features the Svetlana 6550s and Hammond transformers, establishes new output limits—up to 100W.” Indeed, this would become a very popular project at the time, and still is, considering the frequent references. This article was originally published in Glass Audio 3, 2000.

What can you do to ensure the best possible sound from your system? According to Nelson Pass, the “sweet spot” concept is generally regarded as “that happy balance of conditions that elicits the best possible sound,” including the interiors of the components themselves. This article was originally published by audioXpress, January 2010.