SUS-2 - Sustain & Compression Enhancer for Cathode Bias


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The SUS-2 is suitable for cathode-biased amps. It can be used in single-ended or push-pull amplifiers, regardless of whether they are Power Scaled.

The signal envelope has three parts: the initial transient, the sustain portion, and the decay. The transient is about twice the amplitude of the sustain portion and is the part of the sound SUS effects. SUS brings the transient amplitude down to the sustain level, effectively lengthening the sustain time - but only by a short time. This is a subtle effect that alters note attack.

SUS-2 can be fitted to any cathode-biased power amplifier or preamp gain stage, allowing high-bias amplifiers with no inherent sag to exhibit compression effects more akin to fixed-biased amplifiers. A non-critical 16mm pot provides continuously variable compression for any signal level.

PCB included, as well as notes including installation tips + layout and schematic diagrams of the kit.

Assembly is required.

For more info, see "About Our Sag & Sustain Kits".

About London Power

London Power was founded in 1990 by Kevin O'Connor, after two decades of research into innovative audio amplification techniques. Kevin is an audio designer, author and speaker, known for his proprietary methodology called Power Scaling, and for his eleven books on audio subjects. Whether you seek amps, kits or information, you'll find useful answers here on not just the "how" but the "why" of audio amplifier design. Please enjoy the information on this site, and don't hesitate to contact us with questions.

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