Krell Industries 700cx, 400cx, 300cx, 750Mcx, 450Mcx, 350Mcx manual Amplifier Operation

Amplifier Operation

Full Power Balanced amplifiers are easy to install and operate. However, it is important to exercise care during operation, due to the amplifiers’ enormous power output. Switching between active sources (such as a CD player, tape monitor, or VCR) without muting the pre- amplifier output, or bumping or miscuing a source can generate large transients at low fre- quencies. Full Power Balanced amplifiers may generate enough power with these transients to damage loudspeakers.

IMPORTANT

Always mute or fully attenuate the preamplifier level when switching sources.

Do not change input connections to the amplifi- er when the amplifier is on.

Use care when setting high playback levels. Because of their tremendous reserves of clean power, Full Power Balanced amplifiers can safe- ly drive speakers to higher sound pressure lev- els than other amplifiers. Always lower the vol- ume level at the first sign of speaker distress.

ON/OFF AND STAND-BYOPERATION

When powering on any system, turn on ampli- fiers last. Turn off amplifiers first.

1.Move the back panel power breaker switch to the up position to engage the input cir- cuitry and place the amplifier into the stand- by mode. The front panel blue power stand- by LED illuminates.

2.Press the silver power button on the amplifi- er front panel. The blue regulator LED illumi- nates. Once the regulator provides power to the output stage, the blue bias LED illumi- nates. The Sustained Plateau Bias II system is now engaged. After the protection circuitry has confirmed that safe operating conditions exist, the input relays engage. You hear a click. The amplifier is ready for operation.

If the Krell CAST input is being used, the Krell CAST red LED illuminates and remains illuminated at all times during the stand-by or power on modes.

3.With the preamplifier muted or volume con- trol completely lowered, select a source. Increase the volume control to the desired listening level.

4.When turning off the system, mute or com- pletely lower the preamplifier volume, or place the Full Power Balanced amplifier in the stand-by power mode by pressing the power button on the front panel. It is now safe to turn off the rest of the system.

Note

For best performance of Full Power Balanced amplifiers, leave the back panel power breaker switch on at all times.

KRELL LINK OPERATION

1.When all components are linked, place each component in the stand-by mode by moving the back panel power breaker switch to the up position. This ensures that all components will be synchronized when signals from the control component are sent to the linked components in the system.

2.When the components are in stand-by, switch the control component to the opera- tional mode from the control component’s front panel or by using the component’s remote control.

The linked components switch to the oper- ational mode simultaneously.

A linked component can be switched between the operational mode and stand-by, individual- ly, from its front panel. Switching a linked com- ponent temporarily breaks the chain of linked components. To re-establish linked operation, return all components to stand-by.

Krell Full Power Balanced X Series Power Amplifiers 15