In an audio mixing console, a channel strip section is disposed on an operation panel on the basis of a group, which is derived by classifying a plurality of input channels and output channels in groups, and using channel strips provided to the channel strip section, a parameter setting can be performed for each of the channels. These outputs can be appended to data profiles of customers and prospects and can be utilized to support decisions involving prospecting, new applicant evaluation, and customer management across the lifecycle. The tube may be one of a plurality of tubes assembled in parallel to a pair of manifolds, and such tubes are preferably oriented so that their integral fins are substantially parallel, with the fin of a given tube extending toward an adjacent one of the tubes. Also, there is no need for an original and a recording sheet to pass different passages of transportation by shearing a common passage of transportation for use by both of them, hence making it possible to materialize downsizing the apparatus, and reducing the cost of manufacture as well.