User Manual

Owner’s Manual
CP400 & CP700
Commercial Power Amplifier
AtlasSound.com – 6 –
Specifications are subject to change without notice.
1601 Jack McKay Blvd. • Ennis, Texas 75119 U.S.A.
Telephone: [phone] • Fax: [phone]
9. Stereo/Parallel/Bridge Switch
This 3 position switch changes the operating mode of the amplier. DO NOT move this switch
when the amplier is powered up and connected to a load.
• Stereo - When the switch is set to this position, the amplier operates as two independent
ampliers. Use this position for stereo program material or for two discreet paging/sound
masking zones.
• Parallel - When the switch is set to this position a single mono input signal is to be used.
Connect the input wiring to either channel 1 OR channel 2. The one input signal will drive
both amp channels. Use this position when two speaker zones are being fed by a mono
signal. (See note below)
• Bridge - When the switch is set to this position, connect the mono input signal to channel
1 ONLY. The speaker load is connected across the two positive terminals as shown in
Figure 7 on page 10. The amplier will deliver approximately twice the voltage across the
load. Please observe the minimum load specication when operating in Bridge mode.
Note: A 6 dB loss of output power will occur when operating in parallel mode. To over come
this loss, connect the positive terminal on input 1 to the positive terminal on input 2 and
connect the negative terminal on input 1 to the negative terminal on input 2. Short lengths of
22-gauge wire can be used.
10. CH1/CH2, Low Impedance Speaker Outputs
The amplier direct speaker outputs bypass the internal constant voltage transformers and are
used for direct connection to loudspeakers. The amplier will operate into 2, 4, and 8 Ω loads
The use of appropriately sized spade lugs is recommended for speaker wire termination;
connect the speaker line common to the “-” terminal and the positive lead to the “+” terminal.
For high power applications, use the proper gauge wire for the speaker connections. Contact
Atlas Sound Tech Support (1-800-876-3333) for assistance in determining the proper size wire.
11. CH1/CH2, 25/70.7/100V Speaker Outputs
The amplier will drive constant voltage speaker loads for use in commercial business music/
paging systems and sound masking systems. The use of spade lugs for terminating and
connecting the speaker home runs is recommended. The speaker line common connects to the
“0” terminal and the positive lead connects to the desired voltage for required system requires
for proper operation (Figures 8,9,10; Pages 11-12).
Calculating Constant Voltage Loads
To calculate the maximum quantity of transformer coupled loudspeakers you can safely
connect to the amplier, rst add up the total number of speakers that will be connected to
one channel of the amplier, then multiply that total speaker number by the tap setting you
plan to use. The result will be the load in watts that the amp output channel will see. It is
good engineering practice to leave a 20% margin below the maximum rated output power
of the amplier. In this case, one channel of the amplier can supply 350 W of power at
70.7V. Derate this by 20%, leaving 280 W of power available for constant voltage speakers.