TOPPING A90 Discrete HiFi Headphone Amplifier

【Fully Discrete NFCA Technology for Superior Sound】
【2 Gain Settings for Versatile Headphone Compatibility】
【Ground Loop Noise Terminator】
【Dual Function: Headphone Amp and Preamp】
【Expanded Input Options with Ext90】
【Precision R2R Volume Control】
【Volume Memory Function for Convenience】