Yamaha SY99 Owner's Manual page 148

sources may be fixed by the choice of algorithm,
and cannot be changed. In such cases, an "F"
will be displayed after the Source (e.g., OP3F)
and the Destination operator explained in
be displayed in uppercase characters (e.g., IN1).
Dst OP1...OP6 (in1, in2): Select the destination
of each feedback source. Each feedback source
can be sent to as many destinations as you like.
Each operator has two inputs, and an operator
can be selected as a feedback destination only if
at least one of its inputs is free. It makes no dif-
ference whether in1 or in2 is used, but remember
that the input levels of each operator are set
independently for in1 and in2. Refer to the
following section 1.3 Algorithm Input.
If both inputs of an operator are already used
by the algorithm connection, "-" will be dis-
played. If both inputs are already used because
of a feedback assignment, "use" will be dis-
played. If the algorithm has a fixed feedback
loop, the feedback destination operator will be
displayed in uppercase characters (e.g., IN1).
The cursor cannot be moved to the Dst setting
for such operators.
Having three selectable feedback sources which can
be sent to any or all other operators allows you to
connect the operators in very complex ways. The
following diagrams show how the operators would
be connected for algorithm 40 when feedback
sources and destinations are set as shown in the
following table. Thin lines indicate the connections
defined by the algorithm, and heavy lines indicate
the feedback connections. Whether a connection be-
tween two operators is the result of the algorithm or
the result of feedback routing has no influence on the
sound.
Algorithm 40
1
6
3
5
2 4
Feedback settings
FB SRC
FB1 OP3F
will
FB2
OP6
FB3 OP5
Resulting connections
Remarks: In previous Yamaha 6-operator FM syn-
thesizers, you had a choice of 32 algorithms each
of which included one feedback loop. The SY99
provides broader possibilities with 45 algo-
rithms, and three feedback loops that can be
sent to more than one operator. In addition,
operators can be modulated by external
waveforms.
Feedback from a carrier: The output level of
carrier operators is automatically adjusted
according to the number of carriers in the algo-
rithm, in order to keep the resulting output
volume consistant. If the nominal output of a
one-carrier algorithm is considered to be 0 dB,
each carrier in a two-carrier algorithm will be re-
duced -3.010 dB, in a three-carrier algorithm
-8.278 dB, in a four-carrier algorithm -9.783 dB,
in a five-carrier algorithm—12.041 dB, and in a
six-carrier algorithm —14.299 dB.
If you use a carrier operator as a feedback
source, be aware that even if the output level of
the carrier operator is the same, the actual out-
put (and therefore the amount of feedback pro-
duced by the carrier operator) will depend on the
number of carriers in the algorithm.
VOICE EDIT MODE
DST OP1 OP2 OP3 OP4
off use IN2
off use off
off in2 off
FB2
FB1
3
FB3
1 2
OP5 OP6
off off use
off off in1
off off in2
FB3
6
5
4
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