HD-HYNUDAL&reg; White HDMI Karaoke Mixer-K9H Online Singing Machine+1 Condenser Mic for Phone DVD Laptop Tablet PC Professional echo process, with professional-grade YAMAHA reverb chipset, making a perfect blend between microphone voice and accompanying sound, so that dont have voice and accompaniment separation any more. Dual microphone interface, support the chorus, can adjust the microphone volume individually. Professional echo effect can be adjusted depending on the occasion, preference, making your voice with the magnetic, catch up with the KTV effect. Supported Apple series mobile phones, IPod, MID, DVD, HD player, Blue-ray DVD, PC and other audio input. Ordinary microphone or headset inserts to the computer directly, the singing voice is dry and with a large current noise. , but K9 have the function of Noise reduction process, filtering the current sound, so can make the voice pure.