Crown Audio S Series Input Sensitivity Switch, Connect to AC Mains, Startup Procedure, Setup

S-SeriesPower Amplifiers

2 Setup

2.7 Input Sensitivity Switch

A two-position Input Sensitivity switch is located on the back panel near the input connectors (Figure 2.12). Your amplifier is shipped from the factory with this switch set to the 1.4V position. At this setting, a 1.4V input signal will drive the amplifier to full power into an 8-ohm load when the level controls are turned to maximum. This setting works best when the amplifier is being driven by equipment with a +4 dBu output — an output level at which most professional equip- ment operates.

If required, the Input Sensitivity switch can be moved to the 26-dB position, so that the ampli- fier provides a fixed voltage gain of 20 (or 26 dB: 1 volt in, 20 volts out). This setting works best with output levels of +10 dBu (2.5 volts RMS) or more. Some brands of DJ mixers, in particular, have output levels in this range.

Selecting the correct sensitivity will allow your equipment to operate at its optimum level and improve the signal-to-noise of the system.

Make sure the amplifier is turned off and the level controls are turned down before you change the switch setting.

Sensitivity Switch

Figure 2.12 Location of Input Sensitivity Switch

2.8 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 connec- tor (ground) is an important safety feature. Do not attempt to disable this ground con- nection by using an adapter or other meth- ods.

Amplifiers don’t create energy. The AC mains volt- age 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 10% variation above or below the amplifier’s speci- fied line voltage and within the specfied frequency requirements (indicated on the amplifier’s back panel label). If you are unsure of the output voltage of your AC mains, please consult your electrician.

2.9 Startup Procedure

Use the following procedure when first turning on your amplifier:

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 indicator- should glow.

4.Turn up the level of your audio source to an opti- mum level.

5.Turn up the Level controls on the amplifier until the desired loudness or power level is achieved.

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.

Operation Manual page 11