Metasonix TS-21 HellFire
The TS-21 Hellfire Modulator is an analog, tube-based distortion rack-module. The Hellfire has many useful applications for musical instruments but was designed especially for synthesizers! That is, you can use it to add some really gritty and unpredictable distortion to your synth and bass lines.
The Hellfire has 3 unique sections: a pentode preamp with VCA input stage, a metastable pulse-width modulator (PWM), and an LFO-controlled waveshaper/switcher based on a unique TV vacuum-tube. With about 5 tubes, this analog technology can give your sounds a unique and "aggressive" edge!
All input/output jacks and control knobs are located right on the front of the 2-space rack-mount unit. A small view-window is at the center of the unit through which you can see the tubes glowing. Distortion can be introduced during the preamp stage. The PWM and Beam controls can then be used to fold, distort and mangle up your sounds with unpredictable but surprising results. The built-in LFO creates a pseudo-panning effect with adjustable rate and stereo beam width using the L1, L2 and SPEED controls. For a gritty new take on analog distortion the TS-21 is an expensive but tempting offer.
PWM circuit: based on 6BQ7-family dual triode tube, produces different pulse shapes, noise bursts, or violent oscillation. Bypass-able.
Images from Metasonix Online.