Do you mean time between playing in the phone?
Time of playing the same ringing tone again or different
ringing tones? Anyway I don't think there is much to do
in those cases, it is up to the phone model how they are
If you mean time between one note, then you have to decrease
the note durations in your file.
If you mean time between messages in sending phase:
then you can speed the sending between messages by
using these AT commands, in order for these to speed
the sending the phone has to support these commands.
AT+CMMS=1 or AT+CMMS=2
M, Forum Nokia
RE: How to loop ringtones without much space in between