Parasound
®
ZoneMaster
™
450 Owner’s Manual
Page 10
Audio Output Connections
Loop Out Jacks
These jacks enable the audio source connected to the zone 1 Input jacks to pass along
or “daisy chain” to
zone 2 or an additional amplifier. Audio from the Speaker Level Input connector is also converted to line
level and routed to the Loop Out jacks. To pass the audio signal from zone 1 to zone 2 use any standard
RCA cables and connected the Loop out jacks to the input of zone 2.
Connecting Speaker Wires
Detach the green speaker output connecting blocks by pulling them away from the ZoneMaster 450 rear
panel. This makes attaching speaker wires far more convenient. Removing them might require a bit of
effort because the connecting blocks are seated very securely. Connect the connecting block’s + and –
terminals to the corresp and – speaker wires. Never combine the – (negative) of two channels
together, doing so will trigger the amp’s protection circuit.
Note:
The minimum speaker load impedance is 2 ohms in Stereo Mode or 4 ohms when
Bridged Mode is selected. When driving low impedance loads ensure that the ZoneMaster
450 has adequate ventilation and is not installed in a cabinet that is totally enclosed.
Note:
The speaker connector blocks accept bare wires as large as AWG12. The ends of
the wires should be twisted tightly and/or lightly tinned with solder to prevent stray wire
strands from short circuiting the amplifier.
Connecting Multiple Speaker to each Channel
The 450 does not have A and B outputs for each channel unlike the other amplifiers in the ZoneMaster line.
This is due to the limited space on the rear panel. Since the Model 450 is stable at 2 ohms you can connect
multiple speakers to each channel. This is done by simply twisting the two positive speaker wires together
and connecting them to the + (positive) speaker output on the 450. The same should be done with the two
negatives and connecting them to the – (negative) speaker output. This is called a parallel connection.
Typical applications for connecting two speakers to a single channel might include a large living room with
four ceiling speakers. Another use could be in a subzone like a bathroom or hallway adjacent to the room
where the main speakers are installed. This adjacent subzone might also use a passive in-wall volume
control to adjust its listening level separately. The ability of the ZoneMaster 450 to drive two pair of
speakers is credited to its high current design.
Channel 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 two 4 ohm speaker
connected in parallel to one channel’s speaker output terminal. When driving 2 ohm loads ensure
the amplifier has adequate ventilation.
Bridged Mode Connections:
When you select the Bridged Mode the L and R channels are
used together as one channel with higher power output. A channel pair, or zone, in Bridged Mode is
capable of driving a 4 ohm load. When you have selected Bridged Mode only use the
L+ and R –
terminals. Only the R channel Input jack and Level control are used. See page 11 for more details.
CONNECTION WARNING:
Never combine the Speaker L & R channel negative (
−
) outputs together.
Some speaker selectors combine the negative connections and are not compatible with the ZoneMaster
450. Combining the negatives of any two channels would cause the amplifier to engage its protection circuit
and could seriously damage the amplifier. L and R channel speakers cannot be wired where they share a
single negative (
−) wire.
