Non-Sound Decoder MX600 - MX638 and Sound Decoder MX640 - MX659 Page 47
CV
Denomination
Range
INC-
Step
Default
Description
LEAD
- CV
#275
Chuff sound
volume at low speed
and no-load
0 - 255
10
60
With this CV the chuff volume can be adjusted
for low speed and
“basic load” (same conditions
as during the
“automated recording run”).
Here, the engine is driven by about 1/10 of its
full speed, adhering to the exact speed is how-
ever not important.
During this adjustment CV #277 is to be left at
“0” (default), so that the setting for “no-load driv-
ing” is not influenced by load factors.
#276
Volume at high
speed and no-load
0 - 255
10
80
Same procedure as in CV #275 above, but for
high speed.
CV #276 defines the “basic-load” chuff sound
volume at full speed. Set the speed regulator to
maximum during this set-up.
#277
Chuff volume
changes according
to load
0 - 255
10
0
=
no
reaction
When deviating from the basic load (as deter-
mined by the “Automated recording of the mo-
tor’s “basic load” factor”, see above), the chuff
beat volume should be increasing (on inclines)
or decreasing on declines (even muted).
CV #277 defines the degree of change, which
must be set to the proper value by trial.
LEAD
- CV
#278
Load change
threshold
0 - 255
10
0
With this CV, a change in volume to small load
changes can be suppressed (i.e. in curves) in
order to prevent chaotic sound impressions.
Suitable settings can only be determined by tri-
al.
#279
Reaction speed
to load change
0 - 255
1
0
This CV determines how quick the sound reacts
to load changes, whereas the factor is not just
time but rather “load-change dependent time”
(= the bigger the change the faster the effect).
This CV is also used to suppress chaotic sound
changes.
Suitable settings can only be determined by tri-
al.
LEAD
- CV
#281
Chuff volume
-
Acceleration
threshold for full load
sound
0
– 255
(internal
speed
steps)
1
1
More powerful and louder chuff sounds should
be played back indicating increased power re-
quirements during accelerations, compared to
“basic load”. The model railroad motor’s current
consumption however does not change notice-
ably during accelerat
ions (can’t be measured
easily), so the effect has to be simulated.
As is the case with the prototype, the increased
sound should be noticeable before the increase
in speed becomes visible, since the latter is a
result of the increased steam volume supplied
to the pistons. It is therefore practical that the
heavy acceleration sound is played back when
the speed has increased by just one speed step
(when no real speed change is noticed), to be
able to control the proper sound sequence with
the speed regulator.
In this fashion, t
he “engineer” can adjust the
sound (by increasing the speed by 1 step) in
anticipation of an imminent incline.
=1: Acceleration sound played back (at full vol-
ume) if speed has increased by just one speed
step.
= 2, 3…. Acceleration sound played back at full
volume only after increasing speed by this
number of speed steps; before that: proportion-
al volume.
#282
Duration of
acceleration sound
0 - 255
=
0 - 25 sec
10
30
=
3 sec
The acceleration sound should remain for a cer-
tain length of time after the speed increased
(otherwise each single speed step would be
audible, which is unrealistic).
Value in CV #282 = time in tenth of a second!
#283
Chuff sound
volume during full
acceleration
0 - 255
10
255
The volume of steam chuffs at maximum accel-
eration is set with CV #283 (default: 255 = full
volume).
If CV #281 = 1 (acceleration threshold set to 1
speed step), the volume defined here is applied
with each speed increase, even if it’s just 1
step.
LEAD
- CV
#284
Threshold for
deceleration sound
0 -255
(internal
speed
steps)
1
1
Steam chuffs should be played back at less
volume (or muted) signifying the reduced power
requirement during deceleration. The sound re-
duction logic is analog to a reversed accelera-
tion (per CV #281 to #283).
= 1: Reduces sound to a minimum (as per CV
#286) when speed is reduced by just 1 step.
= 2, 3 ... sound reduced to minimum after
lowering speed by this number of steps.
#285
Duration of reduced
volume during
deceleration
0 - 255
=
0 - 25 sec
10
30
=
3 sec
After the speed has been reduced, the sound
should remain quieter for a specific time (ana-
log to the acceleration case).
Value in CV #285 = time in tenth of a second!
#286
Volume level during
deceleration
0 - 255
10
20
CV #286 is used to define the chuff volume dur-
ing deceleration (Default: 20 = pretty quiet but
not muted).
If CV #284 = 1 (deceleration threshold set to 1
speed step), the volume defined here is applied
with every reduction in speed (even if de-
creased by just 1 step).
