Large Array Subwoofer Listening Workshop
January 20, 1998
14 JPEG images, typ. 16K each with links to full images.
On January 20, 1998 over 85 members and guests of the AES Pacific Northwest Section (PNW) and the Washington Association of Production Services (WAPS) converged on the Paramount Theatre in Seattle for a Large Array Subwoofer Listening Workshop. It was an evening of listening, walking, questioning and feeling three industrial-strength subwoofer arrays.
This was the second joint speaker workshop event between the two groups, (the first was held a year ago and we listened to several full-range systems) and there is some crossover between the two sets of members. WAPS was created by companies in the live event production industry in the State of Washington, whose specialties include: Sound, Lighting, Audio-Visual, Motion Picture, Convention, Trade Show, and Special Event services.
WAPS President and AES Committee member Dan Mortensen organized the event. The goal was to listen to an array of each manufacturer's product in a size that might be representative of a small arena system. The overall mouth area of the arrays was limited to 50 square feet each. In the end, three manufacturers were present: Aura Systems, Bag End, and McCauley Sound. Aura provided their Seismic Series RS 8.1 with 8 Aura 1808 drivers; Bag End sent their Quartz system with 16 EL-18A drivers and McCauley came with their Eagle-8 system with 12 model 6174-8 drivers. Each manufacturer sent members of their technical staffs: Barry Bozeman and Ted Leamy (of Electrotec) for Aura Systems, Henry Heine for Bag End, and Tom McCauley and Bruce Anderson for McCauley.
The morning and afternoon were consumed by move-in and testing. Each array was setup and voiced by their own factory personnel. The Paramount's array of Meyer CQ-2s and MSL-4s provided a common mid-high array for each of the three subwoofer arrays. Each sub array used its own crossover-processor and the three resulting highpass outputs were summed and sent to the Meyer mid-high array. Each crossover input received its own send from the matrix section of the Paramount's Yamaha PM4000 mixer.
Testing consisted of voicing, level balancing, and frequency response measurements using both swept-sine on an Audio Precision and TEF measurements. Finally, an AudioControl Industrial IASYS analyzer provided power compression data. All of this information was compiled and duplicated for each attendee. In addition to the IASYS, AudioControl Industrial provided six SPL meters and placed them on stands located throughout the auditorium, giving attendees continuous unweighted SPL readings from a variety of locations. The "official" SPL reference microphone was positioned on the face of the balcony (a large boundary zone), and connected to a very bright and large LED display which was located center stage and visible throughout the theater. McCauley also provided lunch pizzas for the set-up crews.
Of course, the evening was the fun part. Each manufacturer spoke for 15 minutes about their system, then played 10 minutes of their favorite demo material. Before intermission and refreshments, PNW Chair David Scheirman and Dan Mortensen held the random drawing for door prizes donated by Aura Systems - 10 Aura Interactor Cushions. This device connects to one's computer game and you sit on it for a visceral experience while playing.
The remainder of the evening consisted of ABC system comparisons. There was no shortage of program material: pink noise, sweeps, bass guitar, kick drums, synthesizer parts, and music. Musical selections ranged from Toccata & Fugue in D-minor to Bassgasm to Jennifer Warnes. A train wreck from the movie, The Fugitive, provided an interesting source of low-frequency energy.
Listening at high levels (isn't that how these systems are supposed to be operated?), there was no shortage of bass. For anyone who has ever wanted more bass, this was their moment. 100 feet from the array, parts of the building were still being set in motion, and the chest-cavity compression effect was still very apparent. As you moved closer, the experience became even more physical; the visceral experience heightens the low-frequency energy already saturating your auditory system. Even closer, I found the effect one of almost giddiness. It was difficult to speak, let alone think, and I had to consciously suppress my desire to move further away. SPL readings at the balcony showed peaks over 120 dB (flat); higher levels were seen down front. Attendees had been advised to bring ear protection, and earplugs were made available.
This was not a contest; it was a listening workshop. Attendees were given extensive instructions on the test methodology and evaluation techniques. Everyone left with their own impressions. On much of the program material, the three systems sounded quite similar. Each of the systems sounded best on different program material. Their strengths were brought out at one part of the evening or another. The three systems represented very unique and individual engineering approaches to the problems of high-level low-frequency sound reproduction. In spite of these differences, all performed very well; never to the detriment of the others.
The AES PNW Section and WAPS would like to thank Aura, Bag End and McCauley for their participation; AudioControl Industrial, Armstrong/Boyce Marketing, Carlson Audio, Dansound, First Choice Marketing, Mackie Designs, Morgan Sound, Paradise Cases and Pro Sound, Rick Fisher/RFI Mastering, Uneeda Audio, and the Paramount Theatre and its staff Allan Bagley and David Allen.
Nobody left for the lack of bass.
Back to the AES PNW Homepage