I’m writing a piece that has a jazz horn trio (trumpet, alto sax, trombone) in the ensemble. Playback is fine and normal as long as I don’t include basic articulations (accent, marcato, staccato, tenuto, etc.), but as soon as I do, playback adds a low, blatty, tuba-farting noise to it. This only happens with the brass GM sounds ([GM 057] Trumpet, [GM 058] Trombone); other brass patches are fine.
Running Dorico 1.1.10.202 on macOS Sierra 10.12.6, 2017 27" 5K iMac.
Have you changed the sounds in HALion from the default ones that were loaded? If so then have you also reset the expression maps (eg to the default or CC11 map)? If you are hearing low pitches then that suggests that it’s still set to use the HSO expression maps, which the GM patches don’t support.
I have the same problem with the GM brass sounds. The same problem occurs when I load a custom Expression Map on a second or third VST instrument. Can’t exactly see why there is a low sound. I have also used chords.
None of the GM sounds have any keyswitches, so if you have manually changed a sound to a GM patch then you must set the expression map back to ‘default’ or ‘CC11 Dynamics’ otherwise you will hear the keyswitches as normal notes.