Korg A1 Owner's Manual page 24

3. Parallel Chain
4. Key-In Chain
5. Send/Return Chain
In a Parallel Cham, signals are split and multiple processing is done In parallel.
In a Parallel Chain. the MIXER effect cannot be replaced with another effect.
A Key-in Chain Is a Chain which uses the input signal from the right channel as a key-in
signal. In this case the right channel input signal is used only for effect control, and is not
output as a sound source. The effects which are subject to key-in signal control are the
Limiter effects and the Gate, effect.
In all 4 Key-In Chains, the "key" input signal runs through an effect before it is connected
to the GATE or UMITER. This effect on the Key-In signal is called a "Key effect".
Key Effect Applications
Using an EQ on the Key-In signal allows you to create dynamic processing effects such
as Frequency Compensated or Weighted Limiting and Frequency Selective Gating. For
example; use the PEOL (low parametric EG} to lower the frequencies of the Key-In
signal before it is sent to the Limiter. The Limiter will now compress only the high
frequencies and net affect the lows, it is also possible to set up an EQ with the GATE
effect so that it only opens when it "hears* your selected frequency.
A Send/Return Chain allows external devices to be inserted into the A1's effect Chain.
The SEND and RETURN jacks on the rear panel function only when a Send/Return
Chain is selected. A Send/Return Chain has a mono input and the right channel input is
disabled.
Note: During signal input, the return jack is inoperative in SEND/RETURN chains.
(The Rch signal of the digital input is input as a return signal to the send/return mixer.