AMI NiteHAWK, Инструкция по установке и эксплуатации

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NiteHAWK Internet Jukebox Sound System Setup
22022613 Rev A 3-3
Low Impedance Speakers
Low impedance speakers (8- or 4-ohm) can be used when the connecting cable is less than 100
feet. Keep the following two things in mind when wiring your speakers:
1. No more than one 4-ohm speaker should be connected to a speaker line. If several 4-ohm
speakers are to be used, each speaker should have its own line.
2. The loss in 100 feet of 18-gauge zip-cord feeding on an 8-ohm speaker is 15%. The loss for
two 8-ohm speakers is 30%.
Selecting Speaker Power
General Instructions
This section will lead you through the power and speaker selection process. This process
consists of three
major steps and several smaller steps. The major steps are:
1. Identify the extension speakers and compute the speaker power for speakers connected:
a. directly across the amplifier (E1 to E7, or T1 to T7)
b. connected to the 70V taps
c. to lower power taps on the transformer (E1 through E6, or T1 through T6).
2. Make the extension speaker connections.
3. Perform an amplifier overload check (see instructions immediately following
Table 3-6 ).
Selection Procedures
•
Use a pencil (you may want to revise your figures) to fill in the Extension Speaker Worksheet on
the following pages.
•
Extension speakers are available in two general categories: general purpose speakers (4- and
8-ohm), and 70V speakers. Power level in 70V speakers is set at each speaker.
• Use the Tables 3-1 through 3-4 Worksheets to help you calculate the amount of power
consumed by the extension speakers.
• An extension speaker RMS power rating should be at least 10% higher than the power it will
consume at maximum jukebox volume.
When RMS power to speaker
at maximum jukebox volume is:
Then recommended RMS power
rating of speaker is:
250 watts 300 watts
125 watts 150 watts
62.5 watts 75 watts
31.25 watts 40 watts