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CDi Series Power Amplifiers
2 Setup (continued)
2.7 Connect to AC Mains
Connect your amplifier to the AC mains power source (power
outlet) with the supplied AC power cordset. First, connect the IEC
end of the cordset to the IEC connector on the amplifier; then,
plug the other end of the cordset to the AC mains.
WARNING: The third prong of this connector (ground) is an
important safety feature. Do not attempt to disable this
ground connection by using an adapter or other methods.
Amplifiers don’t create energy. The AC mains voltage and current
must be sufficient to deliver the power you expect. You must
operate your amplifier from an AC mains power source with not
more than a 10% variation above or a 15% variation below the
amplifier’s specified line voltage and within the specfied
frequency require ments (indicated on the amplifier’s back panel
label). If you are unsure of the output voltage of your AC mains,
please consult your electrician.
2.8 Protecting Your Speakers
It’s wise to avoid clipping the amplifier signal. Not only does
clipping sound bad, it can damage high-frequency drivers. The
built-in clip limiter prevents clipping.
Also, avoid sending strong subsonic signals to the amplifier.
High-level, low-frequency signals from breath pops or dropped
microphones can blow out drivers. To prevent subsonic signals,
use the amplifier’s DSP to insert a highpass filter (see Section
4.1.6). Alternatively, switch in highpass filters at your mixer. Set
the filter to as high a frequency as possible that does not affect
your program. For example, try 35 Hz for music and 75 Hz for
speech. On each mixer input channel, set the filter fre quency just
below the lowest fundamental frequency of that channel’s
2.9 Startup Procedure
Use the following procedure
when first turning on your
1. Turn down the level of your audio source.
2. Turn down the level controls of the amplifier.
3. Turn on the “Power” switch. The Power indica tor should
4. Turn up the level of your audio source to an optimum level.
5. Turn up the Level controls on the amplifier until the desired
loudness or power level is achieved. NOTE: In Bridge-Mono
mode, only the Channel 1 Level control is functional (except
for CH1 + CH2 Input Y mode).
6. Turn down the level of your audio source to its normal range.
If you ever need to make any wiring or installation changes, don’t
forget to disconnect the power cord.
For help with determining your system’s optimum gain structure
(signal levels) please refer to the Crown Amplifier Application
Guide, available online at www.crownaudio.com.