Thanks for the two very astute responses, guys. Let me outline the strengths and differences between the Triad InRoom Platinum PowerSub and the InRoom Silver PowerSub...
The Platinum uses two of our amplifiers in bridged configuration, for an output of 500 watts into the 18" driver load. The Silver uses an unbridged variation for 250 watts into it's 12" driver. The amplifiers are expensive bipolar output Class AB with toroidal transformers...extremely rare in competitive subs that use cheaper Class D or other amps with poor damping factors. The cast-basket Eminence drivers used in both products have the same 3" edgewound voicecoil and enormous 120 ounce magnet assembly.
The Platinum, with it's huge driver, will typically do better at frequencies below 40-50 Hz, because of the control of the more powerful amp, less excursion for the same output, and more headroom. The lowpass on the Platinum is only 12 dB/octave, so I tend to set it at around 60 Hz with my Platinum LCRs. Although variable, the -3 dB points are almost the same; 18 Hz and 20 Hz.
The Silver PowerSub (also available in an InWall model) has a better motor/mass ratio, and is more articulate above 60 Hz. The articulation is perceptably better because of the dual 12 dB/octave lowpass controls, which allow tailoring of the lowpass, or tandem use of the controls for a steeper 24 dB/octave slope. This is a real fast audiophile sub, and two of them will provide a few dB more output than a Platinum over 50 Hz.
Both the Platinum and Silver have overbuilt enclosures. Anyone wanting to see the inside of the raw cabinet with it's extensive bracing, send me an e-mail and I'll send you some pics. No one uses bracing like this. You'll think we're nuts.
Another consideration is what front speakers are you using? The Platinum may work better with larger fronts that have decent LF response, while the Silver may mate better with smaller fronts.
I'll be out of town doing training after today, but feel free to e-mail with additional questions.
Paul Scarpelli, Director of Sales & Marketing, Triad Speakers, Inc.
Director of Sales & Marketing, Triad Speakers, Inc.