Parasound ZM4 1RU 4 Channel Power Amplifier D class by Pascal

Building on the solid foundations laid by its predecessor the ZM450, the new Parasound ZoneMaster ZM4 punches in with increased size, power and connectivity!

Branching into a bigger frame is the first noticeable difference of the new ZM4 (ZM450 was housed in a half rack width chassis), as it now is a full width 19" 1U rack mount amplifier. This increased footprint is not just aesthetic either, this increased size comes with more bang for buck too in true Parasound fashion! The ZM4 will deliver 120 watts of sonically superior audio quality per channel into 8 Ω and up to 150 watts per channel into a 4 (and yes it's high current design even enables powering loads down to 2 ohm as well).

This power and flexibility is of course bridled with deceptively high fidelity, as can be seen in the ZM4's Class AB input stage plus premium Class D power stage - which is of course the key point of any Parasound product. As with any Parasound product, internal components are 'selected' and chosen for these key principles, they are just not assembled to meet the lowest common denominator of production criteria. Often 'Class D' amplifiers can be overly clinical and to an an extent unmusical - but the ZM4 excels with deep enveloping performance and very adept dynamics more akin to a class AB amplifier, and yet has the benefits (especially within custom installation) of low heat and low power consumption.

Another highly adaptable feature seen on the rear of the ZM4 is the provision of a mono mode, that combines L and R for single speaker applications. This easily overlooked feature means that it can be used highly effectively in corridors, semi commercial installations where stereo imaging is not beneficial and finally a potential 'get out of jail card' for 'compromised' installations too. The ZM4 also features as a consequnce a full range mono RCA output too, so amps can be stacked together and looped together very simply, and with the best level of interconnectivity. The ZM4 also features a useful 'bus' input if required too for simple cohesive zonal or speaker grouping.

This continuance of 'real world'  custom installation credentials can be further seen with automatic on/off by 12 V trigger (with loop) and also automatic on/off by audio signal with adjustable sensitivity. Level controls for each channel are rear mounted and the unit has gold-plated RCA input jacks and looping line output jacks. The ZM4 also benefits from a dedicated speaker level input too, which in certain applications can be deftly used, especially with other distributed audio systems where integration with other components is more commonly done with high level signals opposed to pre-amplified ones.

The ZM4 also has two dedicated zonal speaker outputs also (A & B) per zone - meaning simple and effective connectivity for all speakers without additonal connecting blocks etc. These connectors can accept larger gauge speaker cables to (up to 12 guage) - which inevitably comes in useful for projects with longer runs, or alternately higher quality speaker cables that may require a little bit more real estate. The ZM4 is easily accomodated out of the box for your rack too - as 19" rack ears are included.

So if you are looking for a ultra-flexible but seriously great sounding single zone or dual zone power amplifier, and one that can be used for a multitude of high performance custom installation situations, then you cannot look any further than the new Parasound ZM4 - it is a must for any serious custom installation professional and project.

Features:

• 120 watts x4 @ 8 Ω
• 150 watts x4 @ 4 Ω or 2 Ω
• 8 speaker connections (A and B outputs for both channels)
• High current for stable operation at 2 Ohms
• Class AB input stage plus premium Class D power stage
• Bus input with looping outputs
• Audio sensing auto-on trigger, independent for each zone
• 12 volt auto-on trigger inputs, one for each zone
• Master 12V trigger input to turn all zones on-off together
• Looping 12 volt trigger outputs
• Speaker level input for expanding systems w/out pre out jacks
• Mono mode combines L and R for single speaker applications
• Separate level controls for all 4 channels
• Detachable speaker connectors accept up to 12 gauge wire
• Short circuit and overheat protection with front panel indicators
• 0.5 watt standby power consumption meets Energy Star & EU specs
• Compact 1u chassis size
• Rack mount kit included in the box

Amplifier specifications:

• Power Output – RMS, Both Channels Driven (20 Hz - 20 kHz):
• A+B Outputs of a Single Channel: 2 Ω
• Frequency Response: 20 Hz - 20 kHz, +0/-0.25 dB; 5 Hz - 50 kHz, +0/-3 dB
• Total Harmonic Distortion: < 0.05 % at typical listening levels; < 1.0% at full power
• Interchannel Crosstalk: 70 dB at 20 kHz
• Total Gain: 29 dB (Level controls set to Maximum)
• S/N Ratio: >112 dB, input shorted, IHF A-weighted
• DC Trigger Requirements: +9 Vdc to +12 Vdc, 5 mA
• Audio Trigger Requirements: 2 mV audio signal
• AC Power Requirement: 600 Watts maximum; 60 Watts typical (music playing in all zones); 30 Watts idle (all zones on); 15 Watts idle (one zone on); 250V AC / 50Hz