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Four-Channel, Eight-Speaker Power Amplifier
Parasound's ZoneMaster 4 is a great sounding, highly versatile four-channel, eight-speaker power amplifier with A and B outputs for all eight channels. The compact 1U chassis takes up very little space, and 1U rack mounting hardware is included in the box.
ZoneMaster is Parasound's new line of high-performance amplifiers for custom installation. ZoneMaster amps combine legendary Parasound Class AB sound quality with the most reliable Class D power modules in the industry. Thanks to its high performance, build quality, and Parasound engineering, ZoneMaster is the new standard in residential and commercial amplification.
Among the ZoneMaster 4's many specialized features are a speaker level input for expanding systems without pre out jacks, bus loop output jacks for passing audio to another amp (one bus input can be routed to any zone), mono mode, which combines L and R for single speaker applications, and separate level controls for all four channels.
System integration features include an audio sensing auto-on trigger (independent for each zone), 12 volt auto-on trigger inputs (one for each zone), a master 12V trigger input to turn all zones on-off together, and looping 12 volt trigger outputs. Detachable speaker connectors accept up to 12 gauge wire. ZoneMaster also has short circuit and overheat protection with front panel indicators and 0.5 watt standby power consumption, which meets Energy Star specs.
The Speaker Level Input Connector
The speaker level input is an additional type of audio input that any zone can select as its source. The speaker level input enables the ZoneMaster 4 to connect to any audio receiver or stereo system even if it lacks preamp output jacks.
This is a high impedance input and the ZoneMaster 4’s speaker level input can connect to the speaker terminals on any receiver or amplifier. This will not reduce its output power or degrade the sound quality of the speakers that are already connected directly to the “host” receiver or amplifier. Audio connected to the Speaker Level input connector can be routed to any zone by setting each zone’s Input switch to the Bus position. Speaker level audio is also converted to line level and routed to the Bus Loop Out jacks which provide a line level output to drive additional amplifiers.
Speaker A and B Outputs
The ZoneMaster 4 is equipped with connections for two speakers on each channel (labeled A and B). This unique feature gives system designers greater flexibility and can usually avoid the added expense, complexity, heat and power consumption of additional amplifiers. The ability of the ZoneMaster 4 to drive two pair of speakers is credited to Parasound’s 2 ohm stable high current design.
Typical applications for using both Speaker A and B outputs might include a large living room with four ceiling speakers. Another use for the B speakers could be in a subzone like a bathroom or hallway adjacent to the room where the A speakers are installed. This adjacent subzone might also use a passive in-wall volume control to adjust its listening level separately.
Speaker A and B Impedance
When you select the Stereo Mode the R and L channels are each capable of driving speaker loads as low as 2 ohms. An example of a 2 ohm load is one 4 ohm speaker connected to a channel’s speaker output A while another 4 ohm speaker is connected to the same channel’s speaker output B. When driving 2 ohm loads ensure the amplifier has adequate ventilation.
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
Specifications
Power Output – RMS, Both Channels Driven (20 Hz - 20 kHz): 120 watts x 4 @ 8Ω; 150 watts x 4 @ 4Ω or 2Ω
Minimum Speaker Impedance: A+B Outputs of a Single Channel: 2 Ω (Note: Continuous operation at this minimum impedance might require additional ventilation for the amplifier.)
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); 100-250 VAC 50/60 Hz (automatic)
Dimensions: 17.25" wide, 14.25" deep (16" deep with cables connected) 2.5" high with feet (1.75" high without feet
Weight: 12 lbs.