While nearly all onboard preamps will have your standard Treble, Middle, Bass and Level controls the Darkglass Tone Capsule is actually quite different. Still using a 3 band EQ but instead focusing in on Hi Mid, Lo Mid and Bass controls this preamp has a much wider range of usable sounds as it never gets too boomy or too harsh depending on the sound you are after.
By changing out the Treble control for a Hi Mid control you actually increase the range of sounds you can get from the bass. Normally any time you boost the treble more than the lows you get a really harsh high end that just eats in to the frequency range of the rest of the band. Instead the hi mid control actually boosts usuable frequencies in the guitars midrange never sounding too harsh and never getting the way of the rest of the band.
Here's what Darkglass say about the Tone Capsule
The Tone Capsule is a new, unusual take on onboard preamplifiers. It's designed to respect your instrument's natural character while expanding exponentially the tonal possibilities. The Tone Capsule is unique in the way that it doesn't have a Treble control. The idea was Sheldon Dingwall's: he thought that making a Bass-Mid-Treble was too normal for his liking because everyone does it that way, so he suggested including a second mid control instead. We loved the idea! Specially because the second control could be configured to operate at the higher end of the spectrum, offering all the benefits a standard Treble control (increased clarity and definition when boosting) but with a more natural, less-harsh and noiseless operation. Take the pill and discover a whole new universe of sonic possibilities.
The Tone Capsule can function with either one or two batteries in series for 9V or 18V operation respectively (battery clips not included).
+-12dB @70Hz (potentiometer included).
+-12dB @500Hz (potentiometer included).
+-12dB 2.8kHz (potentiometer included).
30x30x20 (mm) - 1.18x1.18x0.4 (in)