New EPC High-Power GaN-Based Class-D Audio Reference Design Now Available

Encouraging developers to design high-performance Class-D audio amplifiers leveraging GaN FETs, EPC has launched the new EPC9192 reference design enabling high power and high efficiency Class-D audio amplifiers in a modular design that is ideal for customization. The EPC9192 showcases the high performance capabilities of EPC's 200V, EPC2307 eGaN FETs in a ground-referenced, split dual supply Single-Ended (SE) design, delivering an impressive 700W per channel into a 4Ω load.

Unlocking the potential of its best-in-class power MOSFET technology, Infineon Technologies introduced the MERUS 2-channel, analog input, class D audio amplifier multichip module (MCM) MA5332MS, adding a higher power and smaller footprint device to its MERUS technology family. It is a powerful upgrade to its predecessor, offering the same or even higher output power than monolithic alternatives, without a heatsink and 50 percent less footprint.

audioXpress readers have long been anticipating the announcement, and Western Electric finally confirmed that the company is taking orders for the new 91E integrated amplifier. Following the resumed production of the 300B triode tubes at the modern Rossville Works facility, Western Electric now launches a single-ended (SE) high-fidelity amplifier inspired by the 91A, its famous predecessor used in early Hollywood motion pictures. The new SE design offers over 20 watts per channel - a first for the 300B in a totally new design for the 21st Century.

High-end audio adepts do not only like music. Many of them also like to construct their own tube amplifier. For those, Menno van der Veen (electronic design) and Guido Tent (mechanical design and realization) created their newest Valve Amplifier kit: the Vanderveen-Trans-SE10. All parts of the case, the components and the transformers are of the highest quality. The DIYer only has to combine all these fine components into a great amplifier.

This simple single-ended amp project by Pete Millett is a great performer and a very well documented project that was immediately adopted by many DIY'er's. The amplifier achieves good power output and low distortion by employing “E-linear” feedback in the output stage. This article was published in audioXpress, April 2005.

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.

The 150-year-old Western Electric will reintroduce its flagship product to market, the famous 300B electron tube. In time for its 80th anniversary, the 300B is returning to production this year, and the Rossville-based company announced they will restart the manufacturing in a brand new facility. Charles Whitener, Western Electric CEO, also confirmed the company will unveil a new single-ended amplifier called the 91E, as an homage to its famous predecessor the 91A, first introduced in 1936.

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.