... time keep working in 8-12 hourse Function Mp3, FM radio, Amplifier, loudspeaker, microphone, reverberation Digital mini professional portable speaker with ... via headset microphone and voice amplified via speaker box . 2.Music amplifier :When connect the computer or MP3 with the cable ... have function such as FM Radio, USB/TF/MMC input ,music reverb and telecontrol etc.Please feel free to tell me if you ...