Tube model : 6SN7 /6N8P 1. Circuit features: Audio amplification uses only one 6SN7 double triode to complete left and right channel amplification. The change of preamplifier board only changes the installation position of the coupling capacitance: the coupling capacitance of the original M2 main board is suspended outside the PCB board, and the coupling capacitance we designed is installed on the PCB board.
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Leicozic 4-Channel Professional Power Amplifier 1650W per Channel for Subwoofer Stage 90-270 VAC pro Audio Equipment
Aliexpress UK
Use original 6J1 tube. The input and output use gold-plated RCA lotus seat, durable and beautiful! This board has reasonable wiring, beautiful appearance and low current noise. Size: Length 133 Width 89 Height 22MM (excluding tube height).
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Herdio 4-Way Home Power Amplifiers Audio Bluetooth & Aux Mini Amplifier for Bathroom Wall Ceiling Speakers EU/US/UK/AU Plug
Aliexpress UK
Using the classic Dual OP AMP NE5532, high frequency electrolytic capacitor, noise reduction circuit design, no background noise, effective gain audio, improve sound quality. 1 x Audio Preamplifier. Widely compatible with all audio devices.
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12V Universal Car Amplifier Board 600W Mono Car Audio Amplifier Powerful Automobile Stereo Subwoofers Amplifier Car Accessories
Aliexpress UK
・Many sound sources such as HIFI PC sound cards DACs and CD players have high output of signals. Passive preamplifiers are ideal for maximizing sound rendering because there is no powertressa. ・There is a gain for example the output remains 1V when input 1V.
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Audio Mixer 4 Channel High Power Amplifie Sound mixing with Microphone Depusheng UF4-M Digital Board Console for Karaoke Stage
Aliexpress UK
Pretty Sound: Equipped with NE5532 chip, this audio preamplifier board ensures better sound quality with little noise. Chip Model: NE5532. Item Type: Audio Preamplifier Board. 1 x Audio Preamplifier Board.
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16-300Ω HiFi Headphone Amplifier Portable 3.5mm AUX Audio Receiver Music Player Earphone Amplifier For Phone With 3.5MM Cable
Aliexpress UK
Icon Audio Passive Line Pre Amplifier - Available in black ONLY Icon Audio's Passive Line Pre Amplifier is a purer alternative to a full pre amplifier, allowing line level items directly to your power amplifier, with only high quality volume and input switching inbetween. The main reasons for having a full pre amplifier (apart from tone controls and balance which thankfully most high pre amps have dispensed with) are: (1) Voltage gain (for example where your 1 volt tuner output needs to drive a 1.5v power amp input), and...(2) Where the capacitance of very long connecting leads degrades high frequency. However, modern tuners, CD players and phono stages usually have enough output to drive your power amplifier(s) effectively without the need for (1) and in most modern systems you are.
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AIYIMA 1000W Power Amplifier Board HIFI Sound Speaker Amplify Mono Digital AC110-220V Sound Audio Amp For Home Theater
Aliexpress UK
Preamplifier tube model : 6SN7 x 1. Preamplifier PCB Size:178x 120MM, thickness:2.0MM. HiFi resistors and capacitors. Assembled Board ：have solder well （Not included tubes）.
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Ge5654/MA12070 80W*2 Power Amplifier Audio HiFi Sound Amplifier Bluetooth For Home Speaker For Headphone Karaoke Integrated Amp
Aliexpress UK
Pretty Sound: Using dual op amp NE5532 with high frequency electrolytic capacitor and noise reduction circuit design to improve sound quality with high gain. Item Type: Preamplifier. 1 Preamplifier (without power adapter).
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1PCS VTL5C2 DIP-4 High-end Audio Power Amplifier Linear Photocouple
Aliexpress UK