SmartPower Plus - Power Amplifier

SmartPower Plus is the ideal partner for Cyrus hi-fi and AV systems. It is an extremely flexible power amplifier that can evolve from 60wpch into a powerful 110w mono amplifier. As you upgrade your hi-fi system SmartPower Plus evolves to meet your demands, adding power and finesse with each upgrade. You may run your new amp in stereo or mono, with or without the matching PSX-R. Uniquely this chameleon-like quality is achieved without loss of performance so common with lesser bridgeable amps. Auto start and auto power down plus built in (MC-BUS™) system control compatibility make this a truly smart power amp, ideal for AV and multiroom systems and extremely useful as systems are upgraded.

The original Cyrus SmartPower became very successful as Cyrus’ most versatile and fully-featured power amplifier. The SmartPower Plus supercedes this model by bringing together the advanced feature-set established by the SmartPower with the advances in power amplifier voicing developed for the X Power. Although primarily intended to partner the Cyrus integrated amplifier range for bi-amping, the SmartPower Plus packs a few surprises and can be switched to run as a high-power mono amplifier with a Pre Xvs in pre/power systems of up to 120W per channel, when used with an external PSX-R regulated power supply.

Technically competent, the SmartPower Plus ranks highly amongst its peers for technical specifications such as noise, distortion, damping factor and current delivery.

The SmartPower Plus is an excellent upgrade for a Cyrus integrated amplifier, voiced to closely match the Cyrus 8vs, either to upgrade the performance of the internal power amplifier, or to use both the internal power amp and the SmartPower Plus in a bi-amped configuration. The fixed gain structure of the Cyrus range enables any Cyrus power amplifier, such as the SmartPower Plus, to be matched for bi-amping to any Cyrus integrated amplifier with a pre-out connection.

The SmartPower Plus includes a port for connection of the PSX-R power supply. The PSX-R is a high capacity, fully regulated power supply with even more capacity than the internal power supply of the SmartPower Plus. The benefits of the super-quiet DC power from the PSX-R will be primarily experienced as an upgrade in the sound of the system, although the power output of the SmartPower Plus will also be increased, particularly when operating as a mono amplifier. The PSX-R is a straightforward user-fit upgrade with a simple umbilical connection to the SmartPower Plus rear panel and no other internal changes required.

The SmartPower Plus features a sophisticated music-sense circuit with microprocessor control. When the unit is set to low-consumption Standby a high-sensitivity circuit will detect an incoming music signal and switch on the amplifier noiselessly ready for use. A precision timer in the control system will then hold the amplifier on for 4 minutes before resetting to a semi-Standby state. From this state the amplifier can be wakened instantly so that even subtle low-level background music or effects signals will not be lost as the amplifier exits standby. If music is not present for an extended period then the SmartPower Plus will revert back to its true low-consumption standby state.

As an alternative means of power control when used in a Cyrus system, the SmartPower Plus includes connection for the Cyrus MC-Bus system. In this case the intelligence in the control system will detect that the user has chosen to use MC-Bus control and will de-activate the music sensing control system.

For applications with systems where music-sense is not required and MC-Bus is not connected, the music-sensing system may be disabled, temporarily by holding the standby key down when first switching on the SmartPower Plus mains power, or permanently by moving a small jumper connector internally on the PCB.

The computer control system of the SmartPower Plus also monitors the general status of the amplifier and can react quickly enough to protect it from accidental short-circuits, even when running at full power.

The quality lightweight die-cast enclosure of the SmartPower Plus has a myriad of advantages both electrically and mechanically.  The integrated heatsink design enhances the thermal efficiency allowing higher performance to size ratio. Additionally, the non-resonant nature of the alloy minimises microphonic effects, while its non-ferrous composition provides an effective shield from external electro-magnetic disturbances. This also eliminates coupling of the power transformer stray magnetic fields to the sensitive audio circuitry.

Technical Information


Inputs - Phono sockets
Outputs - Bi-wirable Loudspeakers, Chain out
Power Supply - 180VA Toroidal transformer
External - Highly regulated PSX-R upgradeable
Communications - MC-BUS™ System BUS


Power output Stereo - 60W/CH (both driven into 8 Ohms) 90W/CH (both driven into 4 Ohms)
Power output Mono - 110W/CH (both driven into 8 Ohms) 150W/CH (both driven into 4 Ohms)
Power output stereo + PSX-R - 60W/CH (both driven into 8 Ohms) 110W/CH (both driven into 4 Ohms)
Power output mono + PSX-R - 125W/CH (both driven into 8 Ohms) 220W/CH (both driven into 4 Ohms)
Distortion - <0.002%, (1kHz into 8 Ohms) <0.01%, (20Hz-20kHz into 8 Ohms)
Frequency Response - -3 dB at 0.1Hz and 100kHz
Output Current - 30A peak
Sensitivity (RCA input) - 413mV (for 60W stereo into 8 Ohms)
Input impedance - 20Kohm
S/N Ratio - 112dBA (ref 60W)
Dimensions - (H x W x D) 73 x 215 x 360 (mm)
Weight - 4.6kg
Finish - Silver & Brushed Black

Manuals and PDFs


Cyrus Cadence App

Cadence allows you to wirelessly browse and select music through your Cyrus unit. Control most of the playback functions of your Cyrus streaming unit with a flick or tap of a finger on your phone or tablet.
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