User manual TERRATEC SOUNDLAUNDY

[. . . ] Sound LaundryTM TerraTec Edition is an ideal enhancement for audio editing and CD recording programs, especially, if you are in interested in transferring all your treasures from tape, vinyl or even shellac records to CD using TerraTec PhonoAmp. The Sound LaundryTM TerraTec Edition offers almost full functionality comparing to our Sound Laundry Compact TM . It was developed especially for the multi-media user who does not want to spend hours learning complicated processing procedures, as well as the meanings and uses of the neverending parameter adjustments needed by other professional software. Both processing modules, Descratcher and Denoiser require setting up only two parameters for optimization, usually within a few seconds. [. . . ] Since the CPU requirement of the Sound LaundryTM TerraTec Edition is very low (about 30% on a 300 MHz PentiumII for a 16 bit, stereo, 44. 1kHz . WAV file) you can optimize all the parameters while listening to the processing in real-time. Fig. 3: The Processing Section of Sound LaundryTM TerraTec Edition. 6 Algorithmix® Sound LaundryTM TerraTec Edition (English) 5. Descratcher The Descratcher effectively removes clicks and crackles from old vinyl or shellac records, and from audio files contaminated during recording due to switching, digital cross-talk, or thyristor buzz. The descratching algorithm consists of two main parts: the declicking filter and the decrackling filter. While the declicking filter is normally used to remove heavy clicks from old vinyl records or switching noise arising from analogue or digital audio equipment, the decrackling filter removes any remaining, mostly small but dense clicks called crackles. For the declicking of typically polluted vinyl records transferred to the digital domain, a declick value of approximately 50 works well in the most cases. Fig. 4: Typical click in the signal taken from a vinyl record (left) and restored signal (right). The higher the decrackle parameter is set, the more crackles are removed from the original signal. The extreme setting, close to 100, results in a smoothing of the input signal. In general, this parameter can safely be set to 80 without any audible artefacts. In some cases, even an extreme setting up to 100 can still improve the quality of processed audio material. In order to minimize the occurrence of artefacts in the descratching process, the final setting of the declick and decrackle parameters should be performed by critically listening to different parts of the audio file to be cleaned up. We highly recommend using the difference feature of the Playback Section, allowing optimal parameter set-up in a very intuitive way. You can switch between the original input signal and the input/output difference, i. e. , the part of signal removed by the descratching algorithms. This difference signal normally should not contain parts of the original signal you want to preserve. For further remarks on how to optimally set up the decklick and decrackle parameter, see Application Tips. Please note that the difference feature works for both Descratcher and Denoiser simultaneously. Therefore if you want to concentrate only on Descratcher performance, leave both Denoiser faders (threshold and reduction) at zero. Algorithmix® Sound LaundryTM TerraTec Edition (English) 7 6. Denoiser The Denoiser belongs to the so-called single-ended noise reduction systems. This means it does not need any special coding procedure before recording, like in the famous tape noise reduction system from DOLBYTM Lab. It is a tool that efficiently removes any kind of broadband noise from pre-recorded audio tracks. The Algorithmix® Denoiser is a weapon against tape hiss, noise from telephone-call cuts, and residual noise from old records after processing with the Descratcher. In a single-ended noise reduction systems, the user decides which noise characteristics have to be applied to the denoising process. A typical broadband noise profile, optimized for surface noise of vinyl records as well as tape hiss, is used in this version of the Denoiser. [. . . ] But please do not expect miracles if you process material with long gaps or jumps. The information theory says that once the information is lost and there is not enough redundancy in the remaining material, the restoration process for the original material is impossible. In such hopeless cases, experienced mastering engineers try to transfer similar recording parts into gaps using very precise audio editors. The same is if you process material containing so much noise that the original signal is no longer distinguishable. [. . . ]