Expert Audio Reports & Projects

The redesigned AudioAmateur.com website is now up and running. As you’ll see, it is a more modern, user-friendly website than its predecessor. You can access your digital subscription to audioXpress as well as read feature articles, interviews, member profiles, and news. I encourage everyone to bookmark the site and visit each day. Stay informed!

Now let’s focus on this issue.

Did you attend the 2012 Munich High End Audio Fair? If not, no worries. Ward Maas walked the floor and took copious notes on interesting audio products and systems (p. 12).

Backes & Müller BM100 on display that Munich High-End Audio Fair 2012 (Source. Ward Maas)

In the first part of his series on electrostatic speakers (audioXpress9/12), Richard Mains provided tips for selecting the proper materials for an electrostatic loudspeaker (ESL) project. This month he covers the fabrication process (p. 22).

Electrostatic cell fabrication (Source: R. Mains)

Turn to page 26 for a thoughtful product review. Gary Galo provides an analysis of Monarchy Audio’s SE-100 MK2and SM-70 amplifiers.

Here you see a pair of Monarchy SE-100 MK2 monaural power amplifiers. The rear panel shows the unbalanced RCA and balanced XLR inputs, binding posts for loudspeaker connections, and an IEC AC power connector. The front panel sports new oval handles and a cleaner appearance than the original SE-100 Delux amplifiers. (Source: Gary Galo)

This month’s interview is fascinating (p. 32). Walt Jung’s interesting life and audio-related work will inspire you to learn, design, and write.

On page 8, Mike Klasco and Steve Tatarunis describe what’s behind a speaker cone. They detail the functionality of speaker stuffing.

Are you engaged in the “sound system debate”? On page 18, Richard Honeycutt investigates the differences between hollow-state and solid-state amps.

The last article in this issue is a thorough review of B&C’s new 18” woofer (p. 38). According to Vance Dickason, “the 18TBW100 uses a ferrite motor design, which is probably going to be the trend in pro woofer design until neo’s prices drop to a more competitive level.”

The October issue is now available.

AX September: Speaker Special

Each year’s “speaker special” issue is a favorite among audioXpress members and clients. It features in-depth articles about speaker technologies and design projects, without completely ignoring other interesting topics (e.g., tube amps).

This year’s special speaker section features informative articles about a detailed loudspeaker design project and an intriguing electrostatic speaker experiment. We also included a third must-read speaker-related article, but it isn’t in the special section because it focuses on enclosures rather than speaker design. Let’s review each article.

On page 23, George Ntanavaras shares his Horizon loudspeaker design. Inspired by Siegfried Linkwitz’s work, Ntanavaras designed an open-baffle active loudspeaker featuring two woofers connected in series used as dipoles, a woofer/midrange used as a dipole, and a dome tweeter used as a monopole. He details everything from the baffle cabinet design to frequency response adjustments.

George Ntanavaras’s Horizon loudspeaker with front grilles (a) and without front grilles (b).

The Horizon loudspeaker’s dimensions

Turn to page 36 to read about Richard Mains’s excellent electrostatic loudspeaker (ESL) project. Although he started experimenting with hybrid electrostatic speakers about two decades ago, Mains hasn’t lost his passion for them. His article covers techniques relating to ESL fabrication, and includes the materials needed to complete your own project.

Richard Mains experimented with electrostatic loudspeakers. This image shows the diaphragm and stator contacts on the back of the cell (a) and on the front of the cell (b).

The third speaker-related article is about enclosures (p. 8). Mike Klasco and Steve Tatarunis cover the practical uses for enclosures, as well as wood alternatives and experimental design techniques.

The rest of the issue’s content is a nice mix of past and present audio technology. We feature an interesting turntable redesign project and the second part of a series on tube sound.

In the article “A Vintage Turntable Revisited,” Ron Tipton explains recent modifications he made to a 2011 turntable restoration project (p. 12). He describes lengthening the tone arm and why he used carbon fiber tubing.

Ron Tipton completed a second Netronics 350D rebuild. The only remaining original parts are the direct-drive DC motor, the platter, the aluminum nameplate with switches, and the 33-1/3 and 45 RPM speed control.

If you’re into tube sound, flip to page 18 for Richard Honeycutt’s insight on distortion. He covers topics such as distortion signatures and testing.