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Overview: The MTX TH90.4 is a 4-channel, Class-AB amplifier.
It has anodized aluminum heatsinks to dissipate heat generated by the amplifier.
The amp produces 60 watts RMS x 4 at 4 ohms, and 90 watts RMS x 4 at 2 ohms.
Bridgeable: The front and rear channels of the amp are
independently bridgeable. The bridged output is 180 watts x 2 at 4 ohms.
Protection Circuits: The TH90.4 provides protection against
overheating and electrical short circuits.
Gain: The amp's independent front and rear rotary gain controls
continuously variable from 100mV to 6V to match the output of the source unit.
Crossovers: The built-in front and rear crossovers can be
independently set to high-pass,
full-range, or low-pass operation via a 3-way switch. If set to high-pass or
low-pass, the cutoff frequency can be set between 40Hz and 400Hz.
Line Level Input/Output: The line-level signals from the
source unit are input using two pairs of stereo RCA inputs. The amp does not
offer a line-level output.
Speaker-level Inputs: If the source unit lacks RCA outputs,
such as a factory head unit, you can connect the amplifier via speaker-level
inputs. Two plug-in 2-channel input harnesses are included with the amp, which can be
spliced to the head unit's speaker wires.
Power Terminals: The TH90.4 features set screw terminals for
power, ground and remote turn-on. The power and ground terminals will accommodate
up to 4 AWG wire, while the remote turn-on terminal will accept up to 8 AWG
wire. The set screws can be loosened or tightened with the supplied Allen
wrenches. MTX recommends the use of 4 AWG power and ground wires with the
Speaker Connections: The amplifier is equipped with set
screw terminals for the speaker outputs. The terminals will accommodate up to 8
AWG wires, and can be loosened or tightened with the supplied Allen wrench.
5 Year Warranty Terms: This product carries a 5-Year
Prorated Warranty with the following terms:
- Years 1-2: Products found to be defective in materials
or workmanship during the first two years will be, at Mitek's option,
repaired or replaced by Mitek at no charge. The warranty period does not
renew, but continues on from the original date of purchase.
- Years 3-5: The purchase price of an item which becomes
defective after the first two years and prior to the end of the warranty
period will be prorated and credited toward the purchase of a new MTX
product. The amount of proration is determined by dividing the original
purchase price by the number of months in the warranty period (60), then
multiplying the result by the number of months remaining in the warranty