Using pydub to mix and tag promos with bed music

make_promo.py

from pydub import AudioSegment
from pydub import playback as player
import math

raw_promo = AudioSegment.from_mp3("FreshA7__1500.mp2")
tag = AudioSegment.from_wav("FA_tag2.wav")

tag_adjust = round(20 * math.log10(float(raw_promo.rms) / tag.rms), 1)
tag = tag + tag_adjust

print tag_adjust
print len(tag)
print "Promo", raw_promo.rms
print "Tag", tag.rms

promo = raw_promo[:21500]
bed = raw_promo[21500:].fade(to_gain=-14.0, start=0, duration=1500)
bed = bed.fade(to_gain=14.0, start=5000, duration=1500)
bed = bed.overlay(tag, position=1500)
player.play((promo+bed) - 3)
finished_promo = promo+bed
finished_promo.export("FA_finished_promo.wav", format="wav")