Set new tempo as a multiple of current tempo for block

with_bpm_mul  mul (number)

Sets the tempo in bpm (beats per minute) for everything in the given block as a multiplication of the current tempo. Affects all containing calls to sleep and all temporal synth arguments which will be scaled to match the new bpm. See also with_bpm

Introduced in v2.3

Example

use_bpm 60  
  play 50
  sleep 1     
  play 62
  sleep 2     
  with_bpm_mul 0.5 do
    play 50
    sleep 1          
    play 62
  end
  sleep 1           

# Set the BPM to 60
 
# Sleeps for 1 second
 
# Sleeps for 2 seconds
# BPM is now (60 * 0.5) == 30
 
# Sleeps for 2 seconds
 
 
# BPM is now back to 60, therefore sleep is 1 second