Reference Amplifiers Key System Benefits · Q-TuneTM, to seamlessly blend the main speakers with the subwoofers; for Bass Up Front TM · DualModeTM capable, for 1-ohm stereo or 2-ohm mono operation · High efficiency, class AB design · Adjustable 12dB/octave highpass and selectable 12 or 24dB/octave lowpass crossovers DualModeTM capable Allows 1-ohm stereo or 2-ohm mono operation on all GT amplifiers, increasing amplifier flexibility. GT amplifiers excel in both main and subwoofer applications. All models rated from 10Hz ­ 95kHz ±3dB with 100dB S/N (A-weighted) (Power ratings reflect a supply voltage of 12.6vdc.) Boston GT amplifiers incorporate ground breaking DualModeTM operation for reproduction of your music as it was originally recorded and meant to be heard. The GT Amplifiers not only offer high power with high efficiency; DualMode design allows the GT to excel on front-end components for vocal sound quality with low distortion or on high current demanding subwoofers. Every GT amplifier is usable into brutally low impedances (1-ohm stereo/2-ohm mono). In addition, GT amplifiers reside in a low profile, easy-to-install chassis with forced air cooling so that they can be mounted in any position, even upside down! Perhaps for the first time there is an amplifier suitable for use with any Boston loudspeaker, under any use condition. Adjustable 12dB/octave highpass and selectable 12 or 24dB/octave lowpass crossovers GT amplifiers feature variable highpass and lowpass crossovers. These filters can be used together to bandpass a midbass driver or with a subwoofer; using the highpass as a subsonic filter. (12dB lowpass on GT-22 and GT-20) Q-TuneTM User adjustable crossover Q dramatically increases bass impact from the front speakers, without the risk of overloading. Also can be used in subwoofer applications to improve bass impact. Forced Air Cooling Allows all GT amplifiers to be mounted in any position--even upside down. This design also offers reduced weight and increased cooling efficiency over traditional heat sinks. MOSFET output stages Uses N-Channel devices (the fastest available) for the quickest recovery under heavy transient conditions. Aluminum security cover Protects the controls once installed. Sliding track-mounted feet For easy repositioning that allows installers to work around hazards found in all vehicles such as electrical wires or fuel lines; move the feet, not the amp. Optional accessory: GT-RSL Remote Subwoofer Level uses voltage control amplification to adjust subwoofer level, eliminating noise and phase error issues. Key Installation Benefits · Low-profile, easy-to-install chassis · Unique forced air cooling system allows for installation almost anywhere--even upside down · Sliding track-mounted feet for easy repositioning · Recessed RCA jacks decrease amplifier footprint · Top-mounted controls for easy set-up · All input/output connections are located on one side of the amplifier to ease installation and wire management GT-50 GT-42 GT-40 GT-28 GT-24 GT-22 GT-20 7 models (power ratings @ 12.6vdc): GT-28 2 channels 1x1100w (2-ohms) or 2x200w (4-ohms) GT-24 2 channels 1x750w (2-ohms) or 2x120w (4-ohms) GT-22 2 channels 1x375w (2-ohms) or 2x75w (4-ohms) GT-20 2 channels 1x220w (2-ohms) or 2x45w (4-ohms) GT-42 4 channels 2x350w (2-ohms) or 4x75w (4-ohms) GT-40 4 channels 2x190w (2-ohms) or 4x45w (4-ohms) GT-50 5 channels 1x250w (2-ohms) + 4x45w (4-ohms) ...