MTX Audio TA4252 User Manual

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5. Stereo Gain Control – This feature is used to ﬁne-tune the input sensitivity of the ampliﬁer to the source unit’s

output level.

6. Switchable Hi, 12dB / Low, 24dB @ 85Hz X-over– This switch is used to pick the preferred frequency range the

ampliﬁer will play. A high pass, low pass, or full range output may be selected. The upper end of the low

pass crossover is 85Hz at 24dB per octave with a mono output. The lower end of the high pass crossover is

85Hz at 12dB per octave with a stereo output.

7. ThunderEQ (Variable) – This feature will add up to 18dB of low frequency impact to the audio system. The

Bass Boost is centered at 40Hz.

8. Remote Subwoofer Level Control (Remote Gain) – This port allows the use of the optional “remote level

control”. The Remote Subwoofer Control is a bass control module that can be installed in any location within

the vehicle for remote adjustments.

9. StreetWires Connectors – All MTX ampliﬁers include StreetWires connectors for efﬁcient current and

maximum voltage transfer.

10. Speaker Connection – These output terminals are individually labeled for proper speaker connections. When

bridging the ampliﬁer, use the left positive terminal and the right negative terminal only. Warning, do not

bridge the ampliﬁer with an impedance lower than 4 ohm.

11. Power Terminals – This is the main power connection for the ampliﬁer. The power and ground wire size

should be the same gauge.

• GND – The ground wire from this connection must be attached to bare metal on the vehicle. The distance

to the ground should be as short as possible and no more than 18”.

• REM – To turn the ampliﬁer on/off, this terminal must be connected to the source unit’s “remote or electric

antenna” wire.

• +12V – The power wire from this connection must be attached to the positive side of the vehicle battery.

• CAP+ - Capacitor Positive Input – The ideal connection point for the positive side of the capacitor to

increase the ampliﬁer’s performance.

• CAP – Capacitor Negative Input – The ideal connection point for the negative side of the capacitor to

increase the ampliﬁer’s performance.

Before Starting

MTX recommends that you have your new Thunder ampliﬁers installed by an authorized MTX retailer, preferably

MECP certiﬁed. If you do decide to do it yourself, make sure you have read the instructions carefully and have

the following tools:

• Electric drill

•

Phillips bit or screwdriver

• 1/8” bit

•

Wire cutters/crimpers

• Safety glasses

•

X-Acto knife

Disconnect the vehicle’s negative battery connection. Any deviation from the recommended connection

procedures may cause serious damage to the ampliﬁer, speakers, and/or vehicle electrical system. Please

double-check the connections before turning the system on.

Installation

Mounting

Place your Thunder ampliﬁer at the predetermined mounting location. Use a felt pen to mark the exact position

of the mounting holes on the mounting surface. Set the ampliﬁer aside. With a sharp, precise blade cut small

circles in the carpet and padding around the four marks denoting your mounting holes to expose the metal

underneath. Use a center punch to make an indentation in the metal to ensure that you drill the exact position

for the screws.

Note: Please use common sense and make sure that all vehicle wires, gas lines, brake lines, etc. are clear and will

not interfere with the installation. ALWAYS WEAR PROPER SAFETY GLASSES.