Cambridge Audio 840A - Manual (Page 21)

840A Class XD integrated amplifier
Azur Class XD integrated amplifier 21
It is possible to disable the short circuit detection feature by pressing the
SHORT DT button to off when in the 840A System Configure menu. This
would only be required if the loudspeakers have very low DC resistance.
5. Intelligent clipping detection
Indication - Volume is reduced automatically, “CLIPPING” appears on
the front panel display.
Description - CAP5 has the ability to detect when the amplifier starts to
clip or overdrive at its output, which can damage loudspeakers, and
degrade the sound. Clipping distortion
is caused at high volume levels when
the output signal attempts to go
outside the maximum voltage that the
amplifier can provide, causing the tops
of the signal to flatten off. When CAP5
detects clipping the volume will be
automatically reduced down until CAP5
detects an undistorted output.
It is possible to disable the clipping detection feature by pressing the
CLIP DT button to off when in the 840A System Configure menu.
Note: Disabling the clipping detection is not advised as this feature has
been added deliberately to protect the amplifier and loudspeakers.
"OVERLOAD" indication. The amplifier will stay in this state until the
Standby/ON switch is pressed to reset it.
Remedy - The resistance on the loudspeaker terminals is too low. Check
to see if there is a short circuit between the loudspeaker terminals.
Note: If the indication remains the same and multiple loudspeakers are
being used on each loudspeaker output then please remove a pair and
retry. If too many loudspeakers are connected to any amplifier causing
the load resistance to drop too low the amplifier will be overloaded.
CAP5 will detect this situation. If the indication remains the same with
only one set of loudspeakers connected, there may be a fault with one
or both of the loudspeakers.
4. Short circuit detection
Indication - Unit has not come out of Standby, display flashes “SPKR
SHORT”.
Description - During power up from Standby CAP5 performs a check on
the loudspeaker terminals to see if a short across the terminals has
been accidentally introduced (display flashes “SPKR CHECK”). If the
resistance measured across the loudspeaker terminals is too low the
unit will stay in Standby mode until the fault has been removed and
Power up is re-attempted (display flashes “SPKR SHORT”).
Remedy - User related fault. There may be a short circuit between the
loudspeaker terminals. Check all loudspeaker connections before
attempting to switch the unit out of Standby (display will flash “SPKR
CHECK” then “SPKR OK” when short circuit fixed).
Mode
Volume
Mode
Volume
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