TPA3223 2.1-channel HIFI Audiophile Digital Amplifier Optical Fiber Bluetooth 5.1 Inputs. Amplifier chip: TPA3223 1. 1pc TPA3223 2.1-channel High Power HIFI Audiophile Digital Amplifier. 4, D323E default is optical fiber input, when the phone Bluetooth connection to the machine will automatically switch to Bluetooth input.
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