The hardware BBE Sonic Maximizer is one of the longest established enhancer-type products, but it works very differently from the Aphex Exciter that preceded it and produces noticeably different results. Rather than add harmonics, the basic BBE process changes the relative timing and phase relationships of the harmonics occupying different sections of the audio spectrum. The theory behind this is that loudspeakers introduce an opposite phase-smearing effect, which the BBE process largely counters. A three-band processing system is employed, where the mid-band is delayed very slightly relative to the high frequencies and the low-frequency band slightly more so. A second process is included which is a type of dynamic equaliser, modifying the high- and low-frequency content of the program material in response to the program material dynamics. The result is to add a little extra clarity, but without the harshness that can be experienced using some harmonic synthesis methods.
The plug-in version can run as a VST 2 plug-in on Mac OS machines under OS 9 or OS X (but not as an Audio Units plug-in) and on any reasonably up-to-date Windows machine running software that supports Direct X plug-ins. Installation requires 4MB of hard drive space and copy protection is via a reasonably benign serial number system, though the number is so small that I had to find my reading glasses before I could enter it into the install window. The minimum computer spec is quoted as a Power Mac 604e or Intel 486 PC, machines so old that I doubt anyone is using them now for anything more demanding than keeping their feet warm.
The beauty of the BBE process is its simplicity of control: there are only three knobs, and one of those sets the output gain. This is actually very useful as the process can increase the overall level slightly, so matching the output and bypass levels makes it much easier to evaluate what difference the process is actually making. A single Process control knob adjusts the degree of enhancement while a separate Lo Contour knob allows the bass end to be adjusted separately so as to maintain a proper balance with the processed high end. There's a Bypass button on the plug-in itself as well as output level metering with clip indicators.
Testing the plug-in showed that it produces essentially the same results as its analogue rackmount counterparts, so if you already know and like the BBE process, you should take no convincing. Compared with other enhancers, the clarifying effect is quite gentle: perhaps the easiest way to describe the effect is as a subtle blend of traditional enhancement and EQ. It doesn't seem able to clarify the mid-range to the extent that is possible with something like the SPL Vitalizer or Aphex Exciter, but it's definitely possible to improve recordings without making the result sound unnatural. The Lo Contour control is also more powerful than it might first appear to be, as it allows mixes and tracks to be given a lot more low-end punch without muddying the sound. While the BBE wouldn't be my first choice for rescuing 'tragic' mixes, it is handy for providing a final polish and will appeal to those users who feel that many of the alternative enhancement techniques are too heavy-handed.