SUS-1 - Sustain & Compression Enhancer for Fixed Bias


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SUS-1 is suitable for non-Power Scaled, fixed-bias amps.

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.

The SUS-1 a compression side-chain that can be fitted into any fixed-biased amplifier that does not already have Power Scaling. This circuit works around the output stage only. A non-critical 16mm pot provides continuously variable compression for any signal level.

Depending on how the bias supply is generated in the amplifier, our Raw Bias Auxiliary Supply Kit (RBX) may be required for proper functioning of SUS-1. Please contact us with any questions.

PCB included, as well as notes including installation tips and layout + 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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