Well it's slightly more complex than that.
The value range is 0 to 127 (like most Control Change for MIDI, unless documented otherwise), that is the range as per the midi specs.
The Reverb/Delay time is controlled by a knob on your TR8S, 0 is either off or min for sure, 127 is the max value for sure. for instance if the max Reverb time is 4 sec, then it sends 127 as value, and this "maps" to this 4sec, the knob set in the middle would probably be 64 (generally rounded up value), so a good "bet" would be 2sec (or something around, this is an exemple, assuming it's linear (which is rarely the case, read below)).
If roland publish their MIDI SysEX specification, that would help. Note this is mostly useful for people writing applications, not musicians.
I have an ensoniq DP/4, which was at least well documented, typically :
If i use the Hall room reverb the decay time goes from 0.70 Sec to 250.0 sec.. but the step are not by .1..otherwise i would turn the wheel for ever
it does typically :
- 250 sec --> 127
- 120 sec -> 126
- 84.3 sec -> 125
- 63.1 sec -> 124
- 50.3 sec -> 123
- 41.9 sec -> 122
... - 10.4 sec -> 105
- 9.98 sec -> 104
- 9.56 sec -> 103
- 9.16 sec -> 102
- 8.80 sec -> 101
- 8.46 sec -> 100
.... - 0.92 sec -> 3
- 0.88 sec -> 2
- 0.81 sec -> 1
- 0.70 sec -> 0
So unless you have a particular constraint to have an " extremely precise" timing, using your feeling should be easier, and faster
Sorry if it's not helpful.
What are you trying to achieve ? there is maybe a simpler « way »
