Power Ratings: The Sound Ordnance M75-4 is a 4-channel Class
D amplifier with an RMS power rating of 75 watts per channel into 4 ohms, and 110
watts per channel into 2 ohms. The amp can also be bridged into a 4-ohm load for
a power rating of 160 watts (x 2). Power ratings are measured with an input power
of 13.4 volts.
Crossovers: The M75-4 is equipped with independent crossovers
for the front (channels 1 and 2) and rear (channels 3 and 4) channels. Each can be
set to high-pass, low-pass, or full range. The crossover points are continuously
variable from 50 to 750 Hz. The crossover slopes are 12dB per octave.
Bass Boost: The front and rear channels also have independent
Bass EQ settings. The bass boost is continuously variable from 0 to +12 dB and is
centered at 45 Hz.
LED Indicators: There are two LED indicators: a green LED that
illuminates when the amp is powered on, and a red LED that illuminates when the
amplifier is in protect mode due to overheating or a short circuit in the speaker
Power Connections: The power and ground connections are set
screw terminals that will accommodate up to 8-gauge wire. (An 8-gauge amplifier
wiring kit is recommended.) The remote turn-on terminal is a set screw terminal
that will also accept up to 8-gauge wire. A 3mm Allen wrench is required to
tighten/loosen the terminals (included).
Speaker Connections: The speaker terminal can be removed from
the amp, which makes connecting the speaker wires easier. The terminal is mounted
to the chassis of the amp with two screws. Bare speaker wire, up to 12-gauge, is
held in place by screw-clamps on the terminal. A flat blade screwdriver (not
supplied) is required to tighten/loosen the screw-clamps.
Signal Inputs: The amplifier has two pair of stereo RCA inputs,
one for the front channels and one for the rear channels. If your head unit only has
one pair of preamp outputs, you can feed all four amplifier channels by connecting
optional Y-adapters (item number
120RCAY1, sold separately). Front-to-back fader capability is lost
when using Y-adapters.
Fuses: The M75-4 is protected by two internal 30-amp ATM fuses,
accessed by removing the bottom plate. However, removing the bottom plate voids the
warranty, so the fuses are not user replaceable within the warranty period.
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