Meeting Topic: The Evolution of a Home Loudspeaker Design
Moderator Name: Dan Mortensen
Speaker Name: Dana Olson, AES PNW Section Committee
Other business or activities at the meeting: New Chair Dan Mortensen announced the November meeting on drum miking at Robert Lang Studios.
Meeting Location: Shoreline Community College, Rm 818 (music bldg), Shoreline, WA
The PNW Section October 2016 meeting had Dana Olson describe the design process behind his DIY loudspeakers that won top prize at the 2016 Pacific Northwest Audio Society DIY (Do It Yourself) Speaker Competition. Dana is a semi-retired aeronautical engineer and member of the AES PNW Section Committee. 14 AES members and 15 non-members attended the meeting at Shoreline Community College in Shoreline, WA. René Jaeger was also originally scheduled to speak, but was ill that evening.
Terry Olson (no relation) is the organizer of the competition and described how it's run. Briefly, speakers are blind auditioned one at a time, behind a screen, by judges with a score sheet. All must use the same "club" amp and CD source material, and are level matched with an analyzer. Categories are defined by cost and whether a kit or DIY.
Dana is currently semi-retired, consulting on new touch screen technology. He has BS and MS degrees in Aeronautical Engineering from U of W, worked at Boeing on design software, windshear detection, and fly by wire on the Boeing 777, and at Physio Control (Medtronic) in firmware, digital signal processing, ECG measurement signal processing filters, and product development. He's also been a Sr. application engineering manager for capacitance touch screen sensing, and architect for large touch screen and noise rejection systems.
Dana went into elaborate detail to describe his design process for his speaker systems. He spoke about driver parameters, testing and selection, modeling of enclosure characteristics, baffle diffraction and crossover design. He chose to make a 3-way system, with a single 12-inch subwoofer, 7-inch midrange, and a line array of 4 tweeters. Several commonly available software programs aided in design, and some ordinary materials went into the construction, including birch plywood, steel pipe, plastic pipe, a 25 pound barbell, and mattress foam. He figures the parts cost $1200.
Door prizes went to:
Syn-Aud-Con coffee mugs (courtesy Steve Macatee): Joe Grisso and Jayney Wallick
Amprobe DMM (courtesy Rick Rodriguez): Rick Smargiassi
AEA swag bag (courtesy Gary Louie): Ed Gruse
Rane 3 ring binder (Macatee): Ken Lorenzen
AES Convention bag, with 141st Dailies, Voice Coil magazine, Genelec bag (GL): Jeff Thompson
Written By: Gary Louie