Boston acoustics GT28, GT22, GT24, GT20, GT42 User Manual

Reference Amplifiers

ualMode

D

™

c

apable

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.

Key System Benefits

• Q-Tune™, to seamlessly blend
the main speakers with the
subwoofers; for Bass Up Front

™

• DualMode™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

Key Installation Benefits

• Low-profile, easy-to-install chassis

• Unique forced air cooling system
allows for installation almost
anywhere—even upside down

Boston GT amplifiers incorporate ground breaking DualMode™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.

All models rated from 10Hz – 95kHz ±3dB with 100dB S/N (A-weighted)

(Power ratings reflect a supply voltage of 12.6vdc.)

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-Tune

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.

• Sliding track-mounted feet for easy
repositioning

• Recessed RCA jacks decrease
amplifier footprint

op-mounted controls for easy

T

•
set-up

• All input/output connections are
located on one side of the amplifier
to ease installation and wire
management

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.

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)

-20 2 channels 1x220w (2-ohms) or 2x45w (4-ohms)

GT

-42 4 channels 2x350w (2-ohms) or 4x75w (4-ohms)

GT
GT-40 4 channels 2x190w (2-ohms) or 4x45w (4-ohms)
GT-50 5 channels 1x250w (2-ohms) + 4x45w (4-ohms)