History
The Nemesys Gigasampler took the music industry by storm, proclaiming "no more looping", since its sampler software played "endless waves" directly from disk. Giga did this with technology developed and licensed from Rockwell. Since disk space is (sort of) infinite, the idea was that no looping is necessary since memory did not have to be conserved. Even so, Gigasampler does provide looping, and that is good. Gigasampler uses the DOS disk format, since it is a Windows computer program.

Nemesys then expanded their product line to include the Gigastudio, which is essentially Gigasampler 2.0; It has an improved interface, added functionality, and greater polyphony. And finally Giga3 came out in 2004, with many new features

Gigasampler and GigaStudio are very similar - we will refer to them as Giga for the remainder of this article.

Nemesys was recently bought by Tascam; certainly a new chapter to Giga is about to be written.

Synthesis and File Structure
The basic Instrument unit on Giga is the Instrument, or .gig file. A gig file can hold up to 128 Instruments; they hold the parameters and the wavedata to be played. An Instrument holds a maximum 4 (GigaStudio maximum 8) keymaps, arranged in a horizontal mapping system called Regions (same as a Keygroup on Akai samplers, except they do not overlap). You can have a Region for every key on the keyboard, and a Region can specify up to 4 (8 for GigaStudio) samples (called Layers). Stereo interleaved samples are supported (they take up two Layers, of course), but a Region cannot hold both Stereo and Mono samples. You can also specify up to 32 velocity splits (wow), but this is lessened the more Layers you use. The envelopes are semi-regular PADSR's.

Giga also supports Performance files (.prf in Giga 1.0, .gsp in Giga 2.0), which are essentially macros that load Instruments into the different MIDI channels. Translator presently supports the Giga 1.0 .prf format, which can easily be translated into 2.0 .gsp GigaStudio files within Giga.

There are quite a few commercial Giga libraries that use a special compression algorithm; these files won't permit .wav extraction, and make the file smaller in size by about 20%. These .wav aren't looped - but since when is it important for Giga samples to be looped...

Translating and Building Giga Instruments

Since the Fusion is a Bank format, you can convert any format into a new Fusion Bank, or you can insert a conversion into an already existing Bank.

Samples are converted into Alesis's proprietary .afs sample format. The incoming structure is arranged into the Program-Multisample-Sample Fusion structure.

Since there are restrictions on Oscillator-level programming and only 4 Oscillators, somtimes multiple Programs must be created to imitate an incoming Program. Programs like this are prefaced with an asterisk (*) and a Mix is created, which can play mutiple Programs at one time.

Parameter Tolerence can be used to reduce the need for multiple Programs; higher tolerance allows the Translator conversion engine to average programming needs and while the final result will not exactly match in the incoming source, it will be less complicated to deal with. 0% Parameter Tolerance means no averaging will take place, 100% tolerence means the first claim to a parameter will apply to all further ones.

Samples can be stereo in the Fusion.

Translating Out of GigaStudio Format

The Instrument Unit on the Fusion is a Program. A Mix is a Performance type that can define multiple Programs on different or the same MIDI Channels.

Samples will be converted out of the proprietary .afs format and converted into the destination format.

You can also convert an entire Fusion Bank into a Bank-type destination such as SoundFont, Giga, Motif, etc.