2 channel adjustable line convertor. RCA Phono Cables. Line level converter / High-Low converter allows the user to run an RCA cable to an amplifier with a radio that only has speaker wire outputs. Subwoofer Boxes.
eBay
DIYUSER XH-M802 Amplifier Board High and Low Voltage Mixer Tone Board Volume Control Subwoofer PCB Adjustment Amplificador
Aliexpress UK
Line level converter / High-Low converter allows the user to run an RCA cable to an amplifier with a radio that only has speaker wire outputs, Inputs are adjustable as well! Each converter does 2 channels (2 speakers).
eBay
Variable-Speed Fan Cooling Class D 1000W 2-Channel Power Amplifier: LLC Power Switch, High Efficiency/Low Power Consumption
Aliexpress UK
Converts car stereo speaker output to RCA outputs. Allow the addition of 2 or 4 channel amplifier to most stereos without RCA Outputs. This device will convert the factory speaker signal into anRCA output so that your amplifier can read the signal.
eBay
160WX2+220W 2x50W+100W Bluetooth Digital Power Amplifier ZK-HT21 ZK-MT21 2.1 Channel TDA7498E Module High And Low Tone Subwoofer
Aliexpress UK
Converts car stereo speaker output to RCA outputs. Allow the addition of 2 or 4 channel amplifier to most stereos without RCA Outputs. Converts 2 channels of speaker wire to RCA outputs. Features: High to Low 2-Channel Line Output Converter.
eBay
ZK-HT21 2.1 Channel TDA7498E 160WX2+220W Bluetooth Digital Power Amplifier Module High And Low Tone Subwoofer
Aliexpress UK
Two Channel Hi-Lo Line Out Converter is an electronic device that allows any stereo to be easily connected to an external amplifier by connecting directly to the high level speaker output and converting it into a low level female RCA connection.
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25A Power Filter EMI High Frequency Two-stage Power Low-pass Filter Board For Power Supply Amplifier PCB Copper Audio Amplifier
Aliexpress UK
Audio Adapter for Audi A3, S3, A4, S4, and TT This XTRONS 40-pin ISO harness adapter features a high-to-low impedance converter, designed to resolve common issues with Audi vehicles: • Eliminates problems where rear speakers produce no sound or emit static noise after installing an aftermarket stereo. • Specifically addresses static/buzzing issues with BOSE speakers, ensuring clear audio performance. • Provides a perfect fit with factory power cables for Audi stereos, ensuring a seamless installation. Upgrade your audio system effortlessly with this reliable solution.
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6.5w*2 EL34 Vacuum Tube Amplifier Diy Kit High Power Low Distortion Warm voice Bluetooth 5.0 Vu Meter HIFI Amplifier Audio
Aliexpress UK
Allows the addition of amplifier and subwoofer to existing factory systems. Converts car stereo speaker output to RCA outputs. Converts 2 channels of speaker wire to RCA outputs. Allow the addition of 2 or 4 channel amplifier to most stereos without RCA Outputs.
eBay
HT004A Battery 0.1MHz-6GHz Low Noise Amplifier 30dB High Gain LNA Amplifier for Shortwave,FM Radio,RF Power Preamplifier Module
Aliexpress UK
The easy way to add an amplifier to your vehicle without changing your factory head unit. Audio Critical Link 4 Channel Low Level RCA Output Line Converter. 4 Channels in and 4 Channels out.
eBay
TS-VU003 VU Meter Driver Board AC DC 12V-18V Support High Low Level Input Backlight Adjustable for Vacuum Tube Power Amplifier
Aliexpress UK