You Can DIY!: Build a Single-Ended Guitar Tube Amplifier

In this project article for audioXpress, the author shares his guitar tube amplifier, a simple, low-wattage, that any DIYer can easily build. Costas Sarris believes in building simple tube amplifier designs, with simple circuits that he found to work better, particularly when the electric signals carry music information, because the signal distortion is easily handled. This article was originally published in audioXpress, June 2015.

An interesting patent review of a Bipolar Speaker assigned to Definitive Technology, the Maryland-based company that is now part of Sound United. The patent describes a forward-focused bipolar loudspeaker design with front-facing and rear facing driver-arrays, adjusted to generate a front-to-back acoustical output balance equal to a 2:1 ratio (about 6dB reduction) in the output of the rear firing transducers relative to the direct forward output. This article was originally published in Voice Coil, June 2015

In this Voice Coil Acoustic Patents article, James Croft discusses an interesting Transmission Line Loudspeaker patent assigned to three engineers from Bose regarding an electro-acoustic driver and acoustic waveguide that includes “an enclosure, an acoustic transmission line formed within the enclosure, and a plurality of acoustic transducers contained within the enclosure and disposed along a length of the acoustic transmission line.” As Croft notes, this seems to be an improvement over the Tapped Horn loudspeaker architecture patented by Tom Danley, assigned 10 years ago. This article was originally published in Voice Coil, June 2015

Part 1 of an article series that looks at some of the available options and methods to create a low-cost system (emphasis on “low-cost”) for lab-grade audio electronics measurements. Focusing on solutions within easy reach of budget-conscience hobbyists, the goal is to demonstrate how you can generate useful data, similar to the graphs and charts in the audio review magazines, but without the expense. A great test and measurement article series by Stuart Yaniger, which started to be originally published in audioXpress, June 2015.

Introduced during the 137th Audio Engineering Society (AES) Convention in Los Angeles, CA, the new Genelec 8351A Acoustically Coaxial Smart Active Monitor (SAM) System is a tri-amplified studio near-field monitor with an ingenious design that introduces enhanced directivity control at lower frequencies in a relatively small speaker. This brilliant design reflects the Finish brand’s “outside-the-box” thinking improving the reference in recording studios. This article was originally published in audioXpress, June 2015.