Linear Audio Vol4: Volume 4

Linear Audio Vol 4 is the fifth issue of a series of printed bookzines dedicated to technical audio and perception.Guest EditorialIn The case for subjective Listening Tests, Dr. Hans van Maanen argues that there is a large body of circumstantial evidence for audible effects in audio equipment. Although not strictly ‘scientific’, this evidence can be used to determine promising avenues of development.TutorialsBurkhard Vogel discusses The Glowing NoiseMaker - On the demystification of triode noise, developing useful procedures to calculate realistic triode noise figures. Ian Hegglun makes progress Towards a reconciliation of measurements with listening tests with a weighted distortion measurement protocol that much better matches subjective listening tests. TechnologyNelson Pass gives an overview of Static Induction Transistors, from the vintage Sony and Yamaha VFETs to the exciting new PASS-SIT-1 device. Lennart Jarlevang, in Revisiting the SIT Nemesis gets his hands on a couple of PASS-SIT-1 devices and develops a single-ended, transformer output class-A amplifier with excellent sound. Finally, Alfred Hesener presents The “Terrible Twins” – a push-pull amplifier with solid state pentodes based on SITs.Circuit DesignMarcel van de Gevel goes tubes with his elegant Tube based Phono Preamplifier, while Bob Cordell takes another approach with VinylTrak – A full-featured MM/MC phono preamp.System designLes Bordelon takes a wider view of audio DAC system design, Building a Great Sounding DAC with a Little Help from My Friends. Test reportJohn Walton reports on the audibility of audio power supplies in A comparative overview of power supply regulator designs with listening tests and reaches some expected as well as unexpected conclusions.The Way I see itIn Supply Decoupling – Finesse before Brute Force Stan Curtis explains how the indiscriminate addition of decoupling caps can be counter-productive and that a few caps placed with finesse can be more effective and less costly.Book reviewsOvidiu Popa reviews Art Kay’s Operational Amplifier Noise - Techniques and Tips for Analyzing and Reducing Noise and concludes that it’s a worthwhile addition to the opamp designer book shelf.Jan DiddenPublisher/Editor