Abstract: The present invention is related to a recordable device that can record flash disks without computers. There are two slots for general serial buses. Two flash disks can insert into these two slots for mutual copy. A control circuit chooses the file format and the file date according to the selections from the first function key and the second function key and executes the copy command to copy files between the two flash disks. The control circuit controls LED indicators to indicate when the copy command has been executed.

Abstract: An audio collecting device by audio input matrix comprises: a plurality of audio input devices for inputting audio sources and generating a plurality of audio signals; a plurality of sub-processors for connecting with a plurality of audio input devices to process the audio signals and generate audio processing signals of them, respectively; and a main processor electrically connecting with the plurality of sub-processors to process the audio processing signals as inputs for controlling these a plurality of sub-processors to do the synchronously sampling actions.