RX 8407 - Car radio Hifonics - Free user manual and instructions

Product Type	4-Channel Car Amplifier
Number of Channels	4
Power Output RMS @ 4 ohms	4 x 110W
Power Output RMS @ 2 ohms	4 x 200W
Power Output Bridged (Mono)	2 x 400W RMS @ 4 ohms
Frequency Response	20Hz - 20kHz
Signal-to-Noise Ratio	>95 dB
Total Harmonic Distortion	<0.05%
Channel Separation	>60 dB
Damping Factor	>150
Input Sensitivity	0.2 - 4V
Input Impedance	>20 kOhm
Crossover Type	Variable High-Pass / Low-Pass / Bandpass
High-Pass Crossover Range	15Hz - 1kHz
Low-Pass Crossover Range	50Hz - 500Hz
Bass Boost	0dB to +18dB at 45Hz
Remote Bass Control	Yes (optional)
Fuse Rating	4 x 20A
Dimensions (W x H x D)	268 x 63 x 435 mm
Weight	Approximately 3.0 kg
Power Supply	12V DC (negative ground)
Speaker Impedance	2-4 ohms per channel, 4 ohms bridged
Installation Location	Trunk or under seat
Protection Features	Short circuit, overload, thermal

Frequently Asked Questions - RX 8407 Hifonics

What is the minimum speaker impedance for each channel?

The minimum final speaker impedance must not be below 2 ohms per channel. For mono bridged mode, the minimum impedance is 4 ohms.

How do I connect the amplifier in 4-channel mode?

Use two RCA cables from the head unit to the LINE INPUT CH1/2 and CH3/4. Connect front speakers to CH1 (left) and CH2 (right), and rear speakers to CH3 and CH4. Set the INPUT MODE switch to 4CH.

How do I set the input gain?

Turn INPUT GAIN controls to MIN. Set head unit volume to 80-90%. Slowly turn INPUT GAIN clockwise until distortion is heard, then turn back slightly until clean sound is achieved.

Can I use the amplifier with a factory head unit?

Yes, but you may need a line output converter if the head unit lacks RCA outputs. The amplifier's input sensitivity (0.2-4V) is compatible with most factory outputs.

What does the Twin Sub switch do?

When set to ON, the parameters from CH3/4 (gain, crossover, bass boost) are applied to CH1/2 as well, allowing you to control two subwoofers with identical settings. The CH1/2 controls are then disabled.

How do I bridge the amplifier for a subwoofer?

For a single subwoofer, connect it to the + MONO BRIDGED and - MONO BRIDGED terminals from CH3/4 (or CH1/2 in 2-channel mode). Ensure the impedance is at least 4 ohms.

Why is my amplifier going into protection mode?

Common causes: low speaker impedance (below 2 ohms per channel), short circuit in speaker wires, overheating due to poor ventilation, or overload from excessive gain. Check connections and reduce load.

What is the recommended crossover frequency for small speakers?

For speakers smaller than 20 cm (8 inches), set the FILTER to HP and adjust the crossover frequency between 60Hz and 150Hz to protect them from low frequencies.

How do I use the remote bass control?

Set the BASS REMOTE switch to ON. This disables the amplifier's BASS BOOST control. Then use the included remote to adjust bass boost level from 0dB to +18dB at 45Hz from the driver's seat.

What fuse rating should I use for the power supply?

The amplifier has internal fuses of 4 x 20A. For the main power wire, use an inline fuse rated at 80A (sum of internal fuses) or as recommended by the installer. Use a sufficient gauge wire (16-25 mm²).

USER MANUAL RX 8407 Hifonics

Owner's Manual in English Page 9

INSTALLATION & STROMANSCHLUSS

Installationshinweise

3D rendering of a black mechanical component with mounting holes and structural ribs (no text or symbols visible)

Top-down line drawing of a car interior with four seats and four windows (no text or symbols)

Kabelanschlüsse

Top-down line drawing of a car's front view showing dashboard, speaker, and vent (no text or symbols)

Kabelanschlüsse

Top-down line drawing of a car front view showing speaker and floor-mounted components (no text or symbols)

Kabelanschlüsse

Installation of the Amplifier, Electrical Connection 10

4-CHANNEL AMPLIFIER RX 8407

Functions & Controls 11

4-Channel-Mode: 2 Frontspeakers / Stereo & 2 Rearspeakers / Stereo 12

3-Channel-Mode: 2 Speakers / Stereo with 1 Subwoofer / Mono Bridged 13

2-Channel-Mode: 2 Subwoofer / Mono bridged 14

TROUBLE SHOOTING 15

Specification

	RX 8407
Channels	4
Watts RMS/MAX. @ 4 Ohms	4 x 110/220
Watts RMS/MAX. @ 2 Ohms	4 x 200/400
Watts @ 4 Ohms mono bridgedRMS/MAX.	2 x 400/800
Damping Factor	>150
S/N Ratio	>95 dB
Channel Separation	>60 dB
THD&N	<0,05 %
Input Gain	0.2 - 4 Volt
Input Impedance	>20 kOhm
X-Over CH1 & CH2
Filter Switch	HP/OFF/LP(BP)
Low Pass Adjust LP	50Hz - 500Hz
High Pass Adjust HP	15Hz - 1KHz
X-Over CH3 & CH4
Filter Switch	HP/OFF/LP(BP)
Low Pass Adjust LP	50Hz - 500Hz
High Pass Adjust HP	15Hz - 1KHz
Bass-Boost @ 45Hz	0dB - +18dB
Bass Remote Switch	ON/OFF
Twin Sub Switch	ON/OFF
Line Input Switch	4CH/2CH
Fuses	4 x 20 Ampere
Dimensions in mm
Width x Height x Length Heatsink	268 x 63 x 435

All specifications are object to change!

INSTALLATION & ELECTRICAL CONNECTION

General Installation Notes

The amplifier is generally mounted in the rear trunk area but can be mounted in any convenient area such as beneath a seat. Please be sure to locate this unit where you have reasonable air circulation and protection from moisture. When considering the mounting location you should minimize the length of the power and speaker leads. Minimizing both leads will yield a more reliable installation. It is also important to ensure that the heat sink fins are not against a panel or a surface, preventing air circulation. Do not install the amplifier on a subwoofer box or on vibrating parts of the vehicle, since the vibrations can cause damage to the amplifier's electrical components.

Installation of the amplifier

At first you have to pull out the screws of the cover of the amplifier. Then you are abel to remove the cover and now you can mark the location for the mounting screw holes by using the amplifier as a template. Drill holes at the marked locations and firmly fasten the amplifier in place with the mounting screws supplied in the accessory kit. Before drilling or cutting any holes, investigate the layout of your automobile thoroughly:

Take care when working near the gas lines or hydraulic lines and electrical wiring of your car.

Electrical Connection

Ground (GND)

This wire is the electrical ground and must be fastened securely to the vehicle's chassis. The best method is to use a threading sheet metal screw since the threads cut into bare metal. Ensure that all paint or other insulation is removed from around the hole area, and using self tapping screw, securely affix the bare wire ends to the vehicle chassis. Use as short a piece of cable as possible - use the same gauge that is used for the +12V cable. Make sure that the connection is safe, a loose connection may result in amplifier noise and fault condition.

3D rendering of a mechanical component with mounting holes and internal channels (no text or symbols visible)

Remote (REM)

Many music sources have an output terminal for connection of the remote turn-on of the power amplifier. If a radio doesn't have a remote turn-on feature, then you can use the antenna relay wire, which activates the antenna motor. Please note, if the power antenna retracts when the radio is operating, then you cannot use the antenna relay wire to operate the remote turn-on.

Battery Connection (+12V)

This wire is usually connected directly to the positive battery terminal. Ensure that the + power supply wire is fused via an assigned fuse in line with the + power supply wire. Please use a sufficient gauge for the installed amplifiers (16 - 25 mm²). This connection must be completed using spade lug with insulating sleeve.

Fuses

The integrated amplifier fuses protect the units from short circuit and overload. The fuse rating is for 4 Ohm loads (impedance) of the speakers, for 2 Ohm loads the fuses may have to get increased in case of higher power consumption.

Power / Ground / Remote Connection

4-CHANNEL AMPLIFIER - FUNCTIONS & CONTROLS

4-CHANNEL AMPLIFIER - SPEAKER & RCA-CONNECTION

4-Channel-Mode: 2 Frontspeakers / Stereo & 2 Rearspeakers / Stereo

Top-down line drawing of a car interior with four seats and front-mounted doors (no text or symbols)

Interconnect Cable Checklist

• Connect the head unit line outputs with good quality RCA to RCA cables with the LINE INPUT SECTION for CH1/2 & CH3/4 of the amplifier.
• Connect the speakers with the terminal blocks (SPEAKER OUTPUT + CH1 -, + CH2 -, + CH3 - and + CH4 -) of the amplifier.
• The minimum final speaker impedance must not be below 2 Ohms per channel. Too low speaker loads results in too high heat dissipation and may cause the amplifier runs into protection-mode.
• Please observe speaker channel and polarity as printed by the speaker terminal block. Incorrect phasing of the speakers results in total loss of bass response.

Caution Please avoid to connect speaker (-) to the ground or vehicle chassis.

FILTER - Switches & Controls Channel 1/2 & Channel 3/4

• If larger than 20 cm speakers are used, the FILTER selector should be set on "OFF" (Full-range).
• For all smaller speakers ( 8.7cm - 16cm) the FILTER selector should be set on "HP", which eliminates the lowest frequencies and protects the speakers from damages. Set the crossover-frequency between 60Hz - 150Hz, depending on the size of the installed speakers. The Highpass adjustment can be done with the HP control. The crossover-frequency is continuously variable from 15Hz - 1KHz.

TWIN SUB - Switch

- This switch should be set on "OFF" - position.

BASS REMOTE - Switch

- This switch should be set on "OFF" - position.

INPUT MODE - Switch

- This switch should be set on "4CH" - position, when you use two RCA to RCA cables. This switch should be set on "2CH" - position, when you use one RCA to RCA cable. Use the inputs CH3 & CH4 when you only use one RCA to RCA cable for connection with the head unit.

INPUT GAIN - Control Channel 1/2 & Channel 3/4

• Turn the INPUT GAIN - controls on the amplifier to "MIN." - position.
• Turn the head unit volume control to about 80-90% of its full setting.
• Turn the INPUT GAIN - controls clockwise until you hear some distortion.
• Then turn back the INPUT GAIN - controls slightly until you can hear clean sound.

BASS BOOST - Control Channel 3/4

- Turn the BASS BOOST control into "0dB" - position.

REMOTE CONTROL - Channel 3/4

4-CHANNEL AMPLIFIER - SPEAKER & RCA-CONNECTION

3-Channel-Mode: 2 Speakers / Stereo & 1 Subwoofer / Mono bridged

Top-down line drawing of a car interior with speakers and a speaker base (no text or symbols)

Interconnect Cable Checklist

• Connect the head unit line outputs with good quality RCA to RCA cables to the LINE INPUT SECTION CH1/2 & CH3/4 of the amplifier.
• Connect the speakers with the terminal block (SPEAKER OUTPUT + CH1 - and + CH2 -) of the amplifier.
• Connect the subwoofer with the terminal block (SPEAKER OUTPUT + MONO BRIDGED - from CH3/4) of the amplifier.
• The minimum final speaker / subwoofer impedance must not be below 2 Ohms / 4 Ohms mono. Too low speaker loads results in too high heat dissipation and may cause the amplifier runs into protection-mode.
• Please observe speaker channel and polarity as printed by the speaker terminal block. Incorrect phasing of the speakers results in total loss of bass response.

Caution Please avoid to connect speaker (-) to the ground or vehicle chassis.

FILTER - Switches & Control Channel 1/2

• If larger than 20 cm speakers are used, the FILTER selector should be set on "OFF" (Full-range).
• For all smaller speakers ( 8.7cm - 16cm) the FILTER selector should be set on "HP", which eliminates the lowest frequencies and protects the speakers from damages. Set the crossover-frequency between 60Hz - 150Hz, depending on the size of the installed speakers. The Highpass adjustment can be done with the HP control. The crossover-frequency is continuously variable from 15Hz - 1KHz.

FILTER - Switches & Control Channel 3/4

- In 1-Channel-Mode in Mono the FILTER selector should be set on "LP", which eliminates the higher frequencies. The recommended crossover-frequency should be between 60Hz - 150Hz , depending on the size and response of the subwoofer. The lowpass adjustment can be done with the LP control. The crossover-frequency is continuously variable from 50Hz - 500Hz . When you use this setting the HP control is activated as a subsonic-filter. This filter eliminates too low frequencies. The threshold is continuously variable from 15Hz up to 1KHz and should be between 15Hz and 50Hz .

TWIN SUB - Switch

- This switch should be set on "OFF" - position.

BASS REMOTE - Switch

- This switch should be set on "ON" - position, if you want to use remote control. When this switch is set on "ON" - position BASS BOOST - Control of the amplifier is out of function.

INPUT MODE - Switch

- This switch should be set on "4CH" - position, when you use two RCA to RCA cables. This switch should be set on "2CH" - position, when you use one RCA to RCA cable. Use the inputs CH3 & CH4 when you only use one RCA to RCA cable for connection with the head unit.

INPUT GAIN - Control Channel 1/2 & Channel 3/4

• Turn the INPUT GAIN - controls on the amplifier to "MIN." - position.
• Turn the head unit volume control to about 80-90% of its full setting.
• Turn the INPUT GAIN - controls clockwise until you hear some distortion.
• Then turn back the INPUT GAIN - controls slightly until you can hear clean sound.

BASS BOOST - Control Channel 3/4

- The BASS BOOST controls the bass level (only CH3/4) from "0dB - +18dB" at 45Hz.

REMOTE CONTROL - Channel 3/4

- Allows to control Bass Boost via remote control from any location, e.g. from driver's seat.

4-CHANNEL AMPLIFIER - SPEAKER & RCA-CONNECTION

2-Channel-Mode: 2 Subwoofer / Mono bridged

Top-down line drawing of a car front view showing speaker and sound unit (no text or symbols)

Interconnect Cable Checklist

• Connect the head unit's subwoofer line output with a good quality RCA to RCA cable to the LINE INPUT SECTION CH3/4 of the amplifier.
• Connect the subwoofers with the terminal blocks (SPEAKER OUTPUT + MONO BRIDGED - from CH1/2 and + MONO BRIDGED - from CH3/4) of the amplifier.
• The minimum final speaker impedance must not be below 4 Ohms per channel pair. Too low speaker loads results in too high heat dissipation and may cause the amplifier runs into protection.
• Please observe speaker channel and polarity as printed by the speaker terminal block. Incorrect phasing of the speakers results in total loss of bass response.

Caution Please avoid to connect speaker (-) to the ground or vehicle chassis.

FILTER - Switch & Control Channel 1/2 & Channel 3/4

• In 2-Channel-Mode with 2 subwoofers mono bridged set the FILTER selector to "LP"- position, which eliminates the higher frequencies. The recommended crossover-frequency is between 60Hz - 150Hz , depending on the size and response of the subwoofer. The lowpass adjustment can be done with the LP control. The crossover-frequency is continuously variable from 50Hz - 500Hz . When you use this setting the HP control is activated as a subsonic-filter. This filter eliminates too low frequencies. The threshold is continuously variable from 15Hz up to 1KHz and should be between 15Hz and 50Hz .

TWIN SUB - Switch

- When this switch is set on "ON" - position the same parameters of CH 3 & 4 for GAIN, HIGH PASS, LOW PASS and BASS BOOST are also used for CH 1 & 2. When you use this setting the controls of channel-pair CH1/2 are out of function.

BASS REMOTE - Switch

- This switch should be set on "ON" - position, if you want to use remote control. When this switch is set on "ON" - position BASS BOOST - Control of the amplifier is out of function.

INPUT MODE - Switch

- This switch should be set on "4CH" - position. Use the Inputs CH3 & CH4 for connection with the head unit.

INPUT GAIN - Control Channel 3/4

• Turn the INPUT GAIN - controls on the amplifier to "MIN." - position.
• Turn the head unit volume control to about 80-90% of its full setting.
• Turn the INPUT GAIN - controls clockwise until you hear some distortion.
• Then turn back the INPUT GAIN - controls slightly until you can hear clean sound.

BASS BOOST - Control Channel 3/4

- The BASS BOOST controls the bass level from "0dB - +18dB" at 45Hz.

REMOTE CONTROL - Channel 3/4

- Allows to control Bass Boost via remote control from any location, e.g. from driver's seat.

Caution! Please use the Bass Boost carefully. The additional boost may result in clipping or overload.

©

RECARO

RX8407

POWERED BY

HIFONICS

LIMITED EDITION

Distribution:

Audio Design GmbH

Am Breilingsweg 3

76709 Kronau

Tel. [phone], Fax [phone]

www.audiodesign.de