PD Cleaner vs Perfect Declipper

PD Cleaner is a free Windows app for reducing clicks, crackle, hiss, and hum in old recordings, particularly public-domain recordings made before 1926. Drop in a file and it analyzes its era, noise, and clicks; a Clean dial lets you adjust the cleaning. Its voicings cover cylinders, acoustic 78s, and early electric recordings, alongside an uncoloured transfer option. A live before-and-after spectrum analyzer can show a curve, waterfall, or both, and users can solo noise being removed. The app works as a VST3 insert in a DAW or as a standalone program. Folder-based batch processing with one preset is limited to the standalone version. Built-in formats are WAV, FLAC, AIFF, Ogg, MP3, and Opus; a free optional add-on provides AAC and more. It supports 24-bit archival exports and says it does not overwrite the original file. The maker describes it as offline software. The Windows release is open source under AGPLv3, and its build may show an unknown publisher warning when first run.

Perfect Declipper is a Windows audio-repair plugin for recordings damaged by excessive loudness and clipping. It calculates missing clipped information from the data that remains, and can restore clipped audio and some dynamics. Thimeo says results can in many cases be indistinguishable from an unclipped original, while also explaining that lost data makes perfect reconstruction impossible and that several reconstructions may be equally good. Windows downloads include VST2, VST3, and Winamp/DSP plugins. Listed hosts and applications include Adobe Audition, Audacity, Cubase, Cakewalk Sonar, FL Studio, PlayoutONE, Winamp, RadioBOSS, and AIMP. The Windows build is listed for Windows XP SP3, Vista, 7, 8, 10, and 11. A Perfect Declipper plan costs €100 as a one-time purchase, with an optional Delossifier add-on for €130. Licenses last for life and include updates, though new features may cost extra.