ATK Audiotek of Valencia, CA, production sound provider for the annual Grammy Awards telecast for the past 14 years, augmented its audience PA system for this year’s ceremony with prototype subwoofer cabinets utilizing Powersoft’s innovative M-Force transducer technology.
The proprietary sub bass system, designed and developed by ATK in collaboration with consultant Mario Di Cola of Audio Labs Systems in Italy, offers a package that significantly outperforms conventional subwoofers and produces a natural and controlled sound with negligible power compression even at the highest sound pressure levels.
ATK first began evaluating its new subwoofer design on the audience PA during production of the most recent season of “The X Factor” television talent show in Los Angeles.
Each cabinet incorporates an M-Force moving magnet linear motor with a 30-inch polypropylene cone and is driven by a single Powersoft K10 class D amplifier generating 9,000W.
According to Scott Harmala, ATK Audiotek’s CTO and VP Engineering, as the company continues to develop the design, the next iteration will incorporate a specially developed Powersoft amplifier module capable of delivering 15,000W that has been designed specifically for integration with M-Force by Claudio Lastrucci, Powersoft’s head of R&D and co-founder.
“The thing that was shocking to us was how it sounded, the quality of the low end and how tight it was. It’s the tightest sub bass we’ve ever heard,” reports Harmala. “I think that largely has to do with the fact that the motor is such an over-dampened design. There’s instant acceleration and de-acceleration. It sounds like nothing anybody has heard before.”
ATK has implemented M-Force in a short transmission line cabinet design, he elaborates. “The design does load the cone but it doesn’t have the characteristics of a bass reflex ported enclosure, where you have a fairly reactive port resonance.”
While a conventional ported design can extend a cabinet’s usable range down by a half-octave and requires precisely tuned high-pass filtering, he says, this new subwoofer offers low frequency extension in excess of one octave.
“We’ll probably set it for a low frequency cut off around 20 Hz. There’s not much content below that,” he says.
“Because the M-Force motor has so much travel and its cone has so much surface area, this design allows it to create a tremendous amount of SPL at very low frequencies and still be within its operating parameters,” he continues. “The motor’s strength is somewhere in the order of 50 to 60 times greater than even the best 18-inch driver on the market. At 25 Hz it has 8 dB more output than two of our double-18-inch subwoofer boxes.”