Copyright ROMPA® Ltd
McGREGOR AMPLIFIER 14971 OPERATING INSTRUCTIONS
MAINS LEAD
A mains lead is supplied with a moulded plug. Supply voltage is 220-240V 50Hz.
MAINS INLET
A standard I.E.C. mains inlet is fitted to all models. The inlet drawer contains an inline fuse
and a spare. Only use the correct mains voltage and fuse rating as indicated on the amplifier
by the mains outlet.
SWITCH ON/OFF
Ensure all leads are connected and volume controls turned down prior to switching on or off.
Before connecting leads make sure the amplifier is switched off and that the volume controls
are turned to minimum. Power on status is indicated be a red LED or an illuminated front
panel.
INPUT PANELS
Inputs can be overdriven by excessive signal levels. This will cause distortion which can
damage loudspeakers. Some amplifiers are fitted with P.P.I's (peak programme indicators)
which will illuminate to indicate an overdrive condition. If overdriving occurs corrective action
must be taken. Either select a lower sensitivity input if available or lower the channel gain and
then increase the master volume control to retain the required output level. If neither of these
options are possible the input signal level must be attenuated externally. Avoid PPI
illumination.
TONE CONTROLS
When setting up for the first time place all the tone controls to the flat (mid way) position. Set
the volume to approximately three quarters the desired level and adjust the tone controls for
the best sound. Increase the volume to the required operating level and make any minor
adjustments to the tone settings that are necessary. Since room acoustics differ and their
characteristics change as they become crowded it is sensible to check tone settings
frequently. Adjusting tone controls whilst behind the speakers produces inadequate results.
FEEDBACK
Acoustic feedback will occur if the microphone gain is too high relative to the placement of the
speakers. Speakers are easily damaged if feedback is allowed to occur and all precautions
should be taken to prevent feedback. Ensure microphones are used far away and if possible
behind loudspeaker positions.
SPEAKERS
Always use speakers with a high enough power rating for your amplifier. Full power will be
obtained by using a 4ohm speaker. DO NOT load the amplifier with less than 4ohms. Two
8ohm speakers connected in parallel constitute a 4ohm load. An 8ohm load will only produce
about 70% of the maximum amplifier power. If in doubt consult your dealer for advice
regarding correct speaker rating and impedance matching.
VENTILATION
If your amplifier is fan cooled ensure that the air inlet and exit vents are unrestricted.
Restricting the air flow will result in an automatic switch off if the internal temperature rise is
McGREGOR AMPLIFIER 14971, KH 9.11