Fosi Audio ZA3 Mini Stereo Class-D Amplifier — 2-Channel Amp with Subwoofer Output, 48V Power Supply, for Passive Speakers & Home Theater

Next-gen dual-mode design: The compact Fosi Audio ZA3 switches easily between stereo and mono operation to fit different setups. In stereo it delivers up to 155W, and when switched to mono it can output up to 235W. For even greater power, two ZA3 units can be paired in mono configuration to drive a larger audio system. Balanced connectivity & remote trigger: The ZA3 debuts balanced input and a 12V trigger-in for synchronized power control. Its balanced combo audio input accepts both XLR and 1/4" TRS plugs, reducing interference and lowering the noise floor. Audiophile-grade parts and performance: Built around the TPA3255 high-end Class-D amp chip, the ZA3 uses Japanese NCC and ELNA capacitors, German WIMA capacitors, and Japanese Sumida inductors for superior audio fidelity. Measured performance reaches a SINAD of up to 89dB, an SNR up to 106dB, and a very low noise floor of only 150μV. Improved cooling for sustained output: Based on the V3 heat dissipation approach, this model upgrades the cooling system with a larger chassis, relocated side vents, and added dust covers to promote better airflow and stable high-power operation. Op-amp rolling and tuning: The ZA3 provides five swappable op-amp positions covering left and right channel outputs, balanced input, and subwoofer output so you can tailor the sound. Compatible DIP8 dual op-amps include Sparkos SS3602, MUSES02, OPA2604, OPA2134PA, OP249, AD827, RM4558, LM4562, LME49720HA, etc. 48V power supply support makes it ideal for home theater, passive speakers and subwoofer setups.