This Windows-only, stand-alone program reduces noise, hum, clicks, scratches, and other gremlins, but also offers enhancement options such as equalization, dynamics, and even reverb. Originally designed to restore wax cylinder and vinyl recordings as well as for forensics, DC5 has since broadened into a more user-friendly program.
There are two operational modes. FastEdit works on a single file and offers several levels of undo. Classic Mode opens up both source and destination files on screen, saving every change as you go. So, the original file is always available for comparison, as are different stages of the restoration process.
If you just want to get rid of garbage, DC5 is easy to use. Like most systems, continuous noise reduction requires sampling the noise, so the effectiveness of hiss reduction depends on how well the sample represents the noise to be removed. But DC5 can also go much deeper and do batch processing, de-clipping, dynamic (frequency-selective) noise reduction, file conversion, and “pencil editing” for clicks; it can even serve as a programmable audio signal generator, and includes a spectrum analyzer. And there’s much more, as explained in the comprehensive manual.
DC5 calls each process a “filter,” but an additional “multifilter” mode treats each filter as a plug-in for a series chain. You can preview each effect individually, or all simultaneously — powerful stuff.
There are some interface quirks. Undo is Ctrl-U, not Ctrl-Z. Pressing the space bar starts the file from the beginning; to play at the current cursor position, you have to right-click and select “Play from here.” And you can’t just zoom in. You have to select a region, then zoom in so the selection fills the screen.
But these are minor complaints.