Lexicon 300L - REV Owner's Manual page 99

300L Owner's Manual
Lexicon
SPEQ (Spatial EQ)
SPEQ sets the amount of a crossfeed between channels. The signal first goes
through a 6 dB/octave low-pass filter whose frequency is set with BXO. When
SPEQ is set positive (above 0) the crossfeed has a negative sign. When SPEQ
is set negative (below 0), the crossfeed has a positive sign. When the control is
set to either maximum or minimum, the gain in the crossfeed circuit is unity.
The result of this control is to change the separation of low frequency stereo
signals. When the control is raised, low frequencies in the sum (mono) channel
are reduced, and low frequencies in the difference (stereo) channel are raised.
With the control at maximum, low frequency mono signals are completely
removed. This represents an extreme setting which should seldom be needed
in practice.
With material which has stereo bass information, or which contains some
reverberation, the effect of raising SPEQ is to increase the sense of spacious-
ness and depth of the sound. It is particularly useful on material recorded with
panpots, or coincident and semi-coincident microphone technique.
When most of the bass in a recording is in the sum (mono) channel, raising
SPEQ may reduce the bass level. This effect can be compensated for by raising
the overall bass level with the BAS controls. Since both controls use the same
BXO setting, this compensation will be quite accurate as long as SPEQ is set to
less than 3 dB boost.
Small stereo Adjust Page Two
TXO (Independent
TXO sets the crossover point for TBL and TBR. When either is set to full cut,
Treble Crossover)
the level is -3 dB at the frequency set with TXO.
TBL, TBR (Left and Right
These controls allow independent adjustment of left and right treble.
Treble Boost/Cut)
ROT (Rotate)
ROT is similar to BAL, but it treats stereo information somewhat differently. Any
signal panned to the center (mono) will be treated by ROT exactly as it would be
treated by BAL. However, if a signal is panned full right and the control is moved
toward the right, instead of simply being attenuated (as BAL would do) the right
channel is inverted in phase and added to the left channel. A stereo image
appears to rotate when this control is used. Ambient information is preserved
and both channels appear to retain equal loudness.
If stereo material is recorded with a coincident pair of figure-of-eight micro-
phones, moving the ROT slider is exactly equivalent to rotating the microphone
pair. Other microphone arrays and multimicrophone setups do not rotate
perfectly, but using this control is frequently preferable to simply adjusting
balance. The display shows the actual channel gains for a continually panned
source.
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