4. What types of plugin interfaces are there?

First, let's talk about the different plugin interfaces. Theoretically, there are a few historical differences, but in practice, these are becoming less and less relevant. Nowadays, all professional plugin developers create plugins for all relevant formats simultaneously, so the original differences are practically negligible.

The most well-known format we should still highlight is called VST, and it is often used as a synonym for audio plugins of all kinds. The VST interface is widely used, runs on all relevant operating systems, and works with all popular DAW programs, including Ableton Live, Presonus Studio One, FL Studio, Bitwig, and of course, Steinberg Cubase, the creator of the format. VST3 is the current version.

The "big" exceptions are the DAW dinosaurs AVID Pro Tools and Apple Logic Pro X. Both do not support the VST format but use AAX (Pro Tools) and AU (Apple Logic Pro X) instead. AU stands for Audio Unit and is an exclusive format for the Apple macOS operating system. Apart from Logic, software such as GarageBand and the video editing program Final Cut Pro also use AU plugins. Many DAWs on Mac support both VST and AU, but AU is not available on Windows computers.

In general, almost every plugin is now available in VST format, with AAX and AU versions also offered. Additionally, there are so-called plugin wrappers available. They encapsulate formats, allowing you to load a VST plugin in an AU or AAX environment. While this may not always be 100% stable or efficient, it works! Some developers of (free) niche software still stick to the VST format, so with a wrapper, you don't have to miss out on good freeware!

ARA and ARA 2 are other plugin formats that achieve a particularly deep integration with the DAW timeline. They are not tied to the real-time processing of VST3/AU/AAX. Only a few professional specialty tools like Melodyne and Auto Align use these formats particularly effectively. For all other "real-time" effects and instruments, the ARA formats do not offer any advantages, so they remain more of a niche.

On the other hand, there's the relatively new CLAP format, which Bitwig is significantly involved in, but it isn't widely relevant yet. Also worth mentioning are so-called DSP plugins. Their processing is not handled by the computer but by external proprietary DSP hardware, such as AVID HDX or Universal Audio UAD-2. The computer essentially handles the graphics of the plugin, which doesn't heavily burden its resources. However, with the extreme computing power that modern computers now have, DSP plugin systems are losing significance.

What is the difference between plugin effects and software instruments?

The basic difference is simple: effects do not generate sounds but can modify them extensively—unlike instruments, whose primary purpose is to produce sounds. That's why they are also called virtual sound generators, software instruments, soft synths, or even sound libraries.

Plugin-Effekte

Software Instruments