Sample Magic produce an impressive array of sample packs, MIDI files and synth patches, alongside various tutorial books and apps. They even run production courses. It may come as a surprise, then, to learn that Magic AB is their first plug-in. What's more, given their sample and synth pedigree, you'd think it might be a synth of some form. Magic AB is, in fact, a utility designed to help you seamlessly reference external audio files and your DAW sounds in an A/B style. A simple enough idea, and one you'd think someone may have tackled before, but I can't think of another plug-in designed solely for this.
Magic AB is typically placed as the last plug-in on a fader, and you then load reference tracks in its nine available slots. These slots are the so-called B source, while whatever DAW signal is feeding the fader is the A source. The most obvious use for this is A/Bing your master mix against other finished tracks, in which case you'd place it in the last insert slot on your master fader after any effects inserts. However, you can also put it on individual instrument tracks and fire up some individual sounds to reference. The thing to always bear in mind is in most cases it should go after other processing, otherwise later processing (including sub-mixes or master output inserts) will affect what you hear.
The main interface is dominated by the nine B file slots. Playback from these is mutually exclusive, and the output goes to the blue B fader. Meanwhile the output from the DAW track feeds the orange A fader. You switch between each source using the A/B buttons, and you can only listen to one at a time. Each of the B slots includes a file load tab, level slider, power/play button and display button. At the top you get the waveform navigator with an overview section above and zoom area below, and the waveform follows whichever file you trigger. However, during playback you can use the display button to display another slot's waveform while the existing slot continues playing. You cursor inside the waveform display to select the playback start point and also to set the playback loop start/stop points. The handy resize buttons (x1/4, x1/2, x2, x4) allow further loop size adjustments. All slots, including their respective levels and loop points, can be saved as a preset, allowing for tailored reference presets. (Just one word of caution here: the file source saved with the presets remains the same, so if you move source files, AB won't find them.)
Further options include AB mode and crossfade time. The first replaces the zoom focus screen with two large A/B buttons, offering a super clear readout with animated icons. Meanwhile the crossfade option (found in the preferences) sets the transition time between A and B (0 to 2 seconds). While in the preferences, it's worth noting the import audio option. As mentioned above, by default AB assumes that your source files will remain where there are. However, the import audio option copies any files to your user directory so they're always available. In use, I found this option needed activating prior to any file loading to ensure files were copied properly. Finally, a quick note on file type support. Magic AB supports AIFF, WAV, MP3 and AAC (Mac only). However, on Windows, the use of the local OS audio decoders can on occasion limit file compatibility to 16-bit. In fact, they say it's unlikely to be problematic, and 24-bit and 32-bit should work fine. Even so, the caveat is there just in case.
Given its simplicity, it should come as no surprise that AB is very slick to use. Matching levels is easy, and the waveform display and looping combined with the various options for triggering playback make the process of navigating tracks quick and intuitive. I even found myself saving presets to handle different track styles, which allowed me to stay organised and efficient. As noted, AB is also suited to referencing individual sounds. Even so, you do have to keep an eye on any master fader or sub-mix processing, as this will influence things. So although this a possible use, mix referencing is where AB excels and where I'd find most use for it. Although the looping implementation is great, I did find the maximum zoom still came up a bit short, so I'd like to see greater magnification here. And when using AB on club mixes, it would be great to sync the reference playback to the DAW playback, so the two would start and stop together. (Word is that both of these options are in development along with some further refinements.) But aside from these points, AB should easily blend into your working routine.
In practice many of us already have workarounds for referencing sounds, including simply using separate outputs and a hardware mixer, using the software mixer that ships with your interface or simply bouncing reference sections and spinning through them in iTunes. However, all are workarounds, and the great thing about AB is that it's not only simple and self contained, but whichever DAW you happen to be working in, your referencing technique will always be the consistent.