HI Danny
Just to recap on above and a bit more info.
There are 2 things that control midi volume :
1 cntrl 7 volume 0 -127, and cntrl 11 expression (note Velocity) 0 -127
Velocity gets sent by a touch sensitive keyboard by measuring the speed that the key descends the harder you hit em the faster they fall.
However if you are entering the notes in a notation screen they will be given a predetermined value this is often around 64.-90 This figure is adjustable in some software.
In BIAB you can see the note velocity in the piano roll view at the bottom pane, you can modify it by drawing a line with the mouse.
Have a look at this below:

Copied from, MIDI tutorials by SysExJohn

, an extremely good idea if we could map these concepts of loudness to MIDI note velocities. Lo and behold it has already been done. In XGworks, the first "proper" sequencing program I ever used, it uses ppp through fff against the note velocities in both the "staff view" and the "piano roll" windows and also within "list view" window too.

It works like this:
fff = 120.
ff = 104.
f = 88.
mf = 72.
mp = 56.
p = 40.
pp = 24.
ppp = 8.

These are, in fact, centre values, so for instance ppp is from 1 through 8 to 15, pp is 16 through 24 to 31, and so on.

How does this work in practice? Well, using my MU1000 sound module and measuring a note played at the centre values I found a difference from loudest to softest of approximately 52 decibels. Quite a significant dynamic range. In fact with CC#7 set to 100 (MIDI default) I found it difficult to hear the softest note (ppp = 8). Changing CC#7 to 120 made it audible, but then the loudest note (fff = 120) became almost painfully loud!
Hope this is a help ,
Mike

BIAB2021 UltraPlus,AsusN55S1Tbssd, W10/64,Akai EIEpro
Yamaha CVP405,SquireStrat, CoolsoftVMidSynth
Novatation Impulse61 Ctr kbd, Cwalk blab Kontakt

http://mikesmusic.byethost16.com/