ENHANCE 2
STEREOPHONIC ENHANCER
2
CONTROLS & CONNECTIONS
1 PHASE CORRELATION METER
The phase correlation meter is used to gauge the
similarity of the left and right stereo output
channels. The correlation figure can range from
+1 (fully correlated, so no stereo content, only
mono), through 0 (no inter-channel correlation)
to −1 (the two channels are completely in anti-
phase).
A good stereo image is achieved with a
correlation factor between 0 and +1. Negative
correlation however, indicates a phase issue and
is to be avoided. In this case, sound would be lost
if the stereo channels were to be mixed into
mono (for example, loss of bass during playback
on a mono speaker or a subwoofer-equipped
sound system).
Note that at least 100 mV
pp
of signal is required
on both channels to ensure correct phase
readings.
2 BALANCE KNOB AND CV INPUT
Use the balance control to shift the stereo image
left or right.
The gains of both channels are controlled
according to a carefully tailored balance law. The
opposing channel will be attenuated when set to
either extreme position, while the selected
channel will be boosted by +3 dB to maintain
constant loudness. Set to the centre position,
both channels remain at unity gain.
This parameter can be voltage modulated using
the corresponding CV input. With the balance
knob centred, the stereo image will shift fully left
for a CV of −5 V, or fully right at +5 V.
