Korg SDD-3000 Owner's Manual page 12

1) Monaural Outputs
A monaural output is typically used when two amplifiers or a stereo mix is not available. The SDD-3000 has two
monaural (mono) outputs; each provides a variable mix of the Direct and Delayed signals.
a)The front panel VARIABLE Output should be used for most purposes. The nominal level at this jack is only
determined by the Output ATTENUATOR switch, so that a variety of equipment may be connected, according to the
following chart:
Type of Equipment
Musical Instrument amplifiers
Semi -pro P.A. & Recording equip.
Professional P.A. & Recording equip.
b)The rear panel +MIX/MONO Output is generally used when the SDD-3000 is permanently installed in a
studio or PA rack cabinet. The nominal level at this jack is always +4dBm.
2)Stereo Outputs
Using a Stereo output mix enhances almost any effects program by generating an extremely rich, two dimensional
"sound image". Two amplifiers or a stereo PA or recording set-up are naturally required to make use of a stereo effects
mix. Two types of stereo outputs ere provided: the first is mono-compatible and should be used in most recording
situations, while the second generates a somewhat richer effect and will generally produce better results in live
performance. All stereo outputs provide a nominal +4dBm output level.
Stereo 'A'
The stereo 'A' output is produced using the DIRECT and +MIX/MONO Outputs.
The DIRECT Output should be panned all the way to one channel (or connected to one amplifier), while the
+MIX/MONO Output should be panned all the way to the other channel (or connected to the second amplifier).
For maximum effect, LEVEL BALANCE should be set fairly high; some effects may require that
LEVEL BALANCE = 10, with the amplifier volume controls being used to regulate the effect/direct signal balance.
This output mix should be used when making stereo recordings which may be played back in mono. It should also be
used for live effects such as fully stereo echoes, when it is desired to have the direct signal come from one side of the
stage with the echoes coming from the other side.
Stereo 'B'
The stereo 'B' output is produced using the +MIX/MONO and -MIX Outputs.
Each output should be fully panned to a different side of the stereo mix (or connected to a different amplifier).
The Output INV switch must be set to the normal (LED off) position.
This type of stereo output uses the sum (in-phase mix) of the Direct & Delayed signals for one side of the mix, and the
differences (out-of-phase mix) of the Direct and Delayed signals for the other side of the mix.
This output mix should generally be used for live performance, as it provides the fullest sound for effects Like flanging,
chorus and doubling, and also allows the LEVEL BALANCE control to be used in the normal manner.
However, it should not be used in most recording situations, since the recorded effect will 'disappear' whenever the
recording is played back in mono, due to the phasing effect used to create the stereo image.
D) Using stereo outputs with low level equipment
Either pair of stereo outputs may be used with low level equipment such as guitar amplifiers by inserting an external 20
dB pad between each output and the corresponding amplifier input. A suitable pad may be purchased, or constructed
using the following schematic. If constructed, the pads should be housed in a sturdy metal box using Switchcraft or
equivalent quality 1/4" phone connectors.
Output ATTENUATOR Setting
-20dBm
(0.075 Volts)
-10dBm
(0.25 Volts)
+4dBm
(1.23 Volts)