> when deprived of their attack transient, the sounds of two different instruments may become hard to tell apart
A neat trick is playing guitar through a volume pedal. You mute the sound, pluck a string and then swell in the volume pedal. The rest of the ASDR envelope can be created with other effects like delays.
The song Cathedral by Van Halen is a particularly brilliant example of this. Except even more remarkable he used the knob on the guitar to do it rather than a pedal:
A neat trick is playing guitar through a volume pedal. You mute the sound, pluck a string and then swell in the volume pedal. The rest of the ASDR envelope can be created with other effects like delays.