USER GUIDE
30
CARE OF YOUR MIXER
GENERAL PRECAUTIONS
Do Not obstruct any of the ventilation openings.
Avoid storing or using the mixer in conditions of excessive heat or cold, or in
positions where it is likely to be subject to vibration, dust or moisture.
Keep the mixer clean using a soft dry brush, and an occasional wipe with a
damp cloth or ethyl alcohol. Do not use any other solvents which may cause
damage to paint or plastic parts.
Avoid placing drinks or smoking materials on or near the mixer. Sticky drinks
and cigarette ash are frequent causes of damage to faders and switches.
Regular care and inspection will be rewarded by a long life and maximum
reliability.
GLOSSARY
AFL (After Fade Listen)
a function that allows the operator to monitor the post-
fade signal in a channel independently of the main mix.
auxiliary send
an output from the console comprising a mix of signals
from channels and groups derived independently of the
main stereo/group mixes. Typically the feeds to the mix
are implemented on rotary level controls.
balance
the relative levels of the left and right channels of a
stereo signal.
balanced
a method of audio connection which ‘balances’ the
wanted signal between two wires and a screen which
carries no signal. Any interference is picked up equally
by the two wires, which results in cancellation of the
unwanted signal. In this guide, the term can refer to
various circuit architectures. Connection details are
given in relevant sections.
clipping
the onset of severe distortion in the signal path, usually
caused by the peak signal voltage being limited by the
circuit’s power supply voltage.
DAT
Digital Audio Tape, a cassette-based digital recording
format.
dB (decibel)
a ratio of two voltages or signal levels, expressed by the
equation dB=20Log10 (V1/V2). Adding the suffix ‘u’
denotes the ratio is relative to 0.775V RMS.
DI(direct injection)/DI Box
the practice of connecting an electric musical instrument
directly to the input of the mixing console, rather than to
an amplifier and loudspeaker which is covered by a
microphone feeding the console.
direct output
a post fade line level output from the input channel,
bypassing the summing amplifiers, typically for sending
to individual tape tracks during recording.
equaliser
a device that allows the boosting or cutting of selected
bands of frequencies in the signal path.
fader
a linear control providing level adjustment.
feedback
the `howling’ sound caused by bringing a microphone
too close to a loudspeaker driven from its amplified
signal.
foldback
a feed sent back to the artistes via loudspeakers or
headphones to enable them to monitor the sounds they
are producing.
frequency response
the variation in gain of a device with frequency.
gain
the amount of amplication in level of the signal.
headroom
the available signal range above the nominal level before
clipping occurs.
highpass filter
a filter that rejects low frequencies.
impedance balancing
a technique used on unbalanced outputs to minimise the
effect of hum and interference when connecting to
external balanced inputs.
Summary of Contents for Spirit M Series
Page 7: ...33 M8 M12 DIMENSIONS All dimensions are in millimetres Inches shown in brackets...
Page 8: ...USER GUIDE M4 DIMENSIONS All dimensions are in millimetres Inches shown in brackets 34...
Page 9: ...35 APPENDIX 1 TYPICAL CONNECTING LEADS...
Page 10: ...USER GUIDE 36...
Page 11: ...37 SYSTEM BLOCK DIAGRAM...
Page 12: ...USER GUIDE 38...