What’s the difference
I’ve used soundfonts before. What is a VST?
From Sound on Sound :
Q: What is a VST Instrument, and how do they work?
The VST (Virtual Studio Technology) system was developed by Steinberg to enable a complete studio to be created in software. Even in its earliest incarnation, it allowed third-party developers to produce real-time effect modules that could ‘plug in’ to the host application. However, when Steinberg introduced the second version of the VST plug-in standard it also became possible to send MIDI data to and from such effects. This enabled developers to add more features, such as MIDI control of effect parameters and locking of effect settings to tempo. The inevitable result of this advance in the protocol was that this MIDI information was also used to run synth engines, rather than just effects processors. It is these synths, masquerading as effects plug-ins in order to fit directly into the sequencing environment, that are called VST Instruments.
Q What do I need to be able to use VST Instruments?
The most important thing is a suitable VST 2.0-compatible host application. The main ones are Steinberg’s Cubase VST from version 3.7 onwards for PC owners, and from version 4.1 on the Mac, along with the entry-level Cubasis VST, and the latest versions of Emagic’s Logic Audio range, including their entry-level MicroLogic AV 4.5. A few other applications (mostly shareware and freeware) also support VST Instruments, such as the freeware VSTi Host for Mac that turns them into stand-alone synths, and Orion and n-Track Studio, both shareware virtual studios with comprehensive MIDI and Audio support.
You will also need a fairly powerful CPU, since the sounds are created in real time using some of the processing power of your computer – each extra note you play needs more calculations, and thus consumes additional CPU cycles. As a rough guide, you should add together the minimum specifications quoted by both your MIDI + Audio sequencer and the VST Instrument, since you will obviously be running them both simultaneously.
You get soundfont VST instruments as well.
Were you talking about VST or VSTi ?
Good post. Here are some other ways to think about it.
A VSTi or DXi is a plugin instrument. It plugs in to a DAW just like VST and DX effects do (for the most part), only they take MIDI input and play sounds rather than taking audio input and modifying it. (Some plugin instruments can do both, but let’s not get too complicated here!)
A soundfont is a file that contains samples and instructions on how to play the samples in response to MIDI from a keyboard or sequence. It’s a format that is used for SoundBlaster cards, and is also used by “soundfont players” which are a kind of software synth that plays soundfonts. Soundfont is just one format for samples – most sample-based synths have their own formats, like Giga, Halion, Kontact, EXS24, etc. Sounfont format is nice because it’s supported by more than just one manufacturer: it’s an “open standard”.
There are plugin instruments that play soundfonts! A good example is “sfz”, which is free and you can use it to play any soundfont you have enough memory for. (Most soundfont players load the whole sojundfont into memory before starting.)
And there are plugin instruments that just make their own sound by synthesis or modeling something, like Native Instruments B4 which sounds like a Hammond organ and is a lot more complex than a soundfont. There are also plugin synths that sound like a minimoog, for example. In that case, you want to be able to adjust synth controls like a minimoog has, you don’t want to just play samples of a minimoog that’s set up a certain way (which is the best you could do with soundfonts).
A soundfont is built by recording lots of notes at different strengths (e.g., how loud you hit a piano key), and telling the soundfont builder which file to play for each key on the keyboard, and which files are for soft, which are for medium, loud, etc. You don’t have to sample every note, because the soundfont players can pitch-shift the samples to fill the gaps.
Oops - misread your post! Sorry for the non-sequitur parts of the answer. :-/