Sonar 7 is positively bristling with soft synths, including z3ta+ (the subject of last issue's workshop article), the TTS1 GM module, DreamStation, Pentagon I, PSYN II, Roland GrooveSynth, and the underrated Cyclone. And there's another group of soft synths, including DropZone, RXP, SFZ, Session Drummer 2 and LE versions of Dimension and Rapture, that all have something in common: they can load SFZ-format files. Should you care? Yes, you should, and here's why.

The SFZ file format is not unlike the concept of Soundfonts, where you can load a ready-to-go multisampled sound — not just the samples — as one file. We touched on SFZ files in the Sonar workshop in SOS April 2007 (), which described Session Drummer 2 and how to create your own drum kits by collecting various samples, then assigning them to pads with SFZ-format files. However, the SFZ concept goes much further than that simple example, so we'll explore the subject further here.

Unlike Soundfonts, which are monolithic files, the SFZ file-format has two components: a group of samples, and a text file that 'points' to these samples and defines what to do with them. The text file describes, for example, a sample's root key and key range. But it can also define the velocity range over which the sample should play, filtering and envelope characteristics, whether notes should play based on particular controller values, looping, level, pan, effects, and many more parameters.

However, note that not all SFZ­compatible instruments respond to all these commands; if you try to load an SFZ file with commands that an instrument doesn't recognise (possibly due to an SFZ v2 definition file being loaded into an SFZ v1-compatible instrument), the program will generate an error log in the form of a text message. Fortunately, nothing crashes, and the worst that can happen is that the file won't load until you eliminate (or fix, in the case of a typo or syntax error) the problematic command.

It's worth mentioning that the SFZ spec is license-free, even for commercial applications. For example, if you want to sell a set of SFZ-compatible multisamples for use in the Cakewalk synths, you needn't pay any kind of fee or royalty.

Why bother learning about SFZ files? Well, there are three main reasons. Firstly, if you like to create your own sounds you can make far more sophisticated ones for SFZ-compatible instruments if you know how the SFZ format works. The files you create will also load into other SFZ-aware instruments (particularly if you limit yourself to using commands from the version 1.0 SFZ spec). Secondly, by editing SFZ files you can overcome some of the limitations of the LE versions of Rapture and Dimension included in Sonar 7. It's been pointed out that you can't adjust tuning in the LE versions, which can be a real problem if, say, you've recorded a piano track where the piano was in tune with itself, but not tuned to concert pitch and you then want to add an overdub. If you know your way around SFZ, you can edit the tuning of the SFZ file that's loaded into the instrument, and get around the problem that way. Finally, SFZ files facilitate cross-host collaboration. The SFZ Player included in Sonar 7 is a VST plug-in...