This command inserts the channel(s) of one or more audio files into the current document. This lets you create a multi-channel file by combining source files. Note that a source file needn't be mono; it can also be multi-channel, in which case all of its channels are inserted. The command is available from both the Audio menu and the view's context menu. If you use the Audio menu, the source channels are appended to the document. To specify an insert position, i.e. the channel before which the source channels should be inserted, use the context menu, as follows: right-click anywhere within the target channel to display the context menu, and select Insert Channel. In either case you're prompted to select the source file(s). Note that the file dialog allows multiple files to be selected, making it easy to insert many channels at once. Files are processed in alphabetical order. To do the opposite, i.e. separate the channels of a multi-channel file, use Extract.