Bungee

Comparison of audio stretch techniques

July 2024

This is a comparison of currently available audio time- and pitch- stretch implementations. Please be aware that the audio files and data here may contain errors, be unrepresentative of the implementations tested or become outdated.

Implementations

Each implementation tested using its best quality settings.

audacity Audacity 3.4 new time stretch, "high quality" for pitch adjust
bungee Bungee v2.0.18
bungeepro Bungee Pro v1.1.12
elastique Elastique 3.4.5 SDK Demo - pro
paulstretch As included with Audacity 3.1.3
rubberband Rubber Band 3.3.0 with options -r3 --ignore-clipping
signalsmith Signalsmith Stretch 27a5835
sonic Sonic 8694c59
soundtouch SoundStretch v2.3.1
superpowered Superpowered Web Audio SDK V2.6.6
this browser This browser's built-in audio stretch via audio tag's playbackRate property

Listening

A comparison of audio stretch algorithms using short music and speech samples. Headphones or good quality speakers will help to hear properly all the differences.

Empty table cells correspond to time or pitch stretch values unsupported by that implementation.

speed adjustment pitch adjustment
×0.25 ×0.56 ×0.83 ×1.5 -1 +1
audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "BugaBlue" by U.S. Army Blues, CC-BY

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from an instructional LP by Bent Lorentzen, "An Introduction to Electronic Music", via Owen Green

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from Beethoven's Piano Sonata No. 14, recorded by Bernd Krueger, CC-BY-SA via audiotsm

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "Out Of It" by Brad Sucks, CC-BY-SA via audiotsm

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from TSMtoolbox , released under a MIT license

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "Wild Mountain Thyme" by Sláinte, CC-BY-SA 3.0

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "Cloud Rider" by Brett Baker, CC-BY 4.0

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "Out Of It" by Brad Sucks, CC-BY-SA via audiotsm

audacity
bungee
bungeepro
elastique
paulstretch
rubberband
signalsmith
sonic
soundtouch
superpowered
this browser
original

excerpt from "Yesterday" by Kellee Maize (Prod. by ID Labs), CC-BY

Tonal response

A test with selected synthetic sinusoidal and square tones.

The numbers in this table show:

  • frequency error in cents (hundredth semitone units); should be close to zero
  • amplitude of the expected tone in dB; should be close to zero
  • noise amplitude in dB; ideally large negative
speed adjustment pitch adjustment
×0.25 ×0.56 ×0.83 ×1.5 -1 +1
audacity
+0.0
-0.5
-55.5
+0.0
-0.5
-52.0
+0.0
-0.5
-68.8
-0.1
-0.6
-40.0
-0.0
-0.0
-88.2
-0.0
-0.0
-88.1
bungee
-0.0
+0.0
-54.0
+0.0
+0.0
-52.2
+0.0
+0.0
-53.6
+0.0
+0.0
-51.3
+0.0
-0.0
-51.6
+0.0
-0.0
-51.6
bungeepro
+0.0
+0.0
-64.4
-0.0
-0.0
-88.8
-0.0
+0.0
-89.0
-0.0
-0.0
-96.8
-0.0
+0.0
-89.1
-0.0
+0.0
-90.9
elastique
-0.0
+0.0
-88.4
+0.3
-0.0
-34.8
-1.0
-0.0
-38.8
-1.4
-0.0
-34.6
-8.1
-0.0
-47.0
-1.4
-0.1
-44.2
paulstretch
-0.2
-21.4
-4.9
+0.2
-20.4
-5.3
+0.1
-14.1
-4.4
rubberband
+0.7
-0.8
-14.6
+0.0
+0.0
-36.9
-0.0
-0.0
-50.5
+0.0
+0.0
-44.2
-0.0
-0.0
-51.9
+0.0
+0.0
-58.6
signalsmith
-0.0
-0.0
-53.7
+0.0
+0.0
-47.2
+0.0
-0.0
-52.4
-0.0
+0.0
-64.4
-0.0
-0.1
-62.0
+0.9
-0.2
-60.1
sonic
-0.4
-0.0
-42.5
-0.2
-0.0
-45.9
-0.2
-0.0
-45.2
+0.2
-0.0
-46.8
soundtouch
-0.2
+0.0
-47.0
-0.0
+0.0
-97.9
-0.1
+0.0
-43.3
+0.8
-0.0
-34.6
-0.0
-0.0
-53.6
-0.7
-0.0
-36.0
superpowered
-0.0
+0.0
-56.2
+0.7
+0.2
-15.2
-0.0
-1.5
-66.9
-0.1
-2.2
-44.8
+0.6
-2.5
-40.1
this browser
original

audacity
+0.0
-0.5
-49.9
-0.2
-0.5
-49.4
-0.1
-0.5
-58.8
-0.2
-0.5
-52.2
-0.0
-0.0
-56.9
+0.0
-0.0
-56.9
bungee
+0.0
+0.1
-52.9
-0.1
+0.0
-55.4
-0.0
+0.0
-54.3
-0.1
+0.0
-53.8
-0.1
+0.0
-55.4
-0.0
-0.0
-55.4
bungeepro
+0.0
-0.0
-68.0
-0.0
+0.0
-94.5
-0.0
+0.0
-92.2
-0.1
+0.0
-56.0
+0.0
-0.0
-71.9
-0.0
-0.0
-92.6
elastique
-0.0
+0.0
-97.4
-0.9
-0.0
-74.5
-1.1
+0.0
-64.8
-0.2
-0.0
-72.2
-8.1
-0.0
-86.0
-1.4
-0.0
-77.1
paulstretch
+0.5
-25.5
-4.8
+0.0
-18.7
-4.3
+1.6
-21.7
-4.5
rubberband
+0.0
-0.0
-55.2
+0.0
-0.0
-67.5
+0.0
+0.0
-68.5
+0.0
-0.0
-72.7
+0.0
-0.0
-68.6
+0.0
-0.0
-72.4
signalsmith
-0.4
-0.0
-43.6
+0.0
-0.0
-51.4
+0.0
+0.0
-64.9
+0.0
-0.0
-65.3
+0.7
-0.1
-55.5
+4.0
-0.1
-57.8
sonic
-0.4
-0.0
-57.9
-0.2
-0.0
-61.9
+0.0
-0.0
-96.2
+0.3
-0.0
-62.4
soundtouch
-0.6
-0.0
-50.9
-0.0
-0.0
-97.6
-0.4
-0.0
-59.7
-0.8
-0.0
-53.5
+0.3
+0.0
-59.6
+0.4
+0.0
-55.1
superpowered
-0.5
+0.0
-45.2
-0.5
-0.0
-52.7
+73.2
-1.4
-17.8
+0.0
-16.7
-4.3
+84.8
-6.1
-8.7
this browser
original

audacity
+0.5
-0.6
-39.7
-0.9
-0.6
-38.7
+0.4
-0.5
-46.8
+0.2
-0.5
-48.6
+0.2
-0.0
-72.3
+0.2
-0.0
-72.1
bungee
+1.0
+0.1
-48.3
-1.0
+0.0
-42.2
+0.9
+0.0
-51.7
+0.3
+0.1
-45.8
-0.4
+0.0
-54.6
+0.3
-0.0
-53.3
bungeepro
+0.0
+0.0
-70.3
+0.0
+0.0
-73.0
-0.0
+0.0
-86.8
+0.5
+0.1
-47.9
-0.0
+0.0
-60.3
-0.0
-0.0
-76.8
elastique
+0.0
+0.0
-91.0
-0.9
-0.0
-72.7
-1.1
+0.0
-69.8
-0.2
-0.0
-77.1
-8.1
+0.0
-77.0
-1.4
-0.0
-76.8
paulstretch
+0.0
-21.9
-3.9
-4.7
-18.9
-4.6
+0.2
-29.7
-5.1
rubberband
-0.7
+0.0
-55.6
-0.2
-0.0
-66.5
+0.0
-0.0
-72.1
+0.0
+0.0
-76.4
-0.0
+0.0
-68.0
+0.0
+0.0
-69.3
signalsmith
-9.2
+0.3
-35.1
+0.7
-0.0
-54.0
-0.2
+0.0
-65.5
-0.4
+0.0
-59.8
+26.5
-0.2
-52.8
+22.6
-0.2
-54.7
sonic
+91.4
-0.1
-20.4
+62.5
-0.1
-25.4
+5.4
-0.0
-34.2
-82.8
-0.1
-27.5
soundtouch
-18.1
-0.0
-34.7
+0.0
-0.0
-93.8
+4.7
-0.0
-38.0
-0.0
-0.0
-69.9
-13.2
-0.0
-32.9
-2.0
+0.0
-44.3
superpowered
+20.3
-0.0
-35.2
-2.4
-0.0
-48.5
-290.5
-1.5
-16.8
-3.6
-2.6
-42.8
-1.6
-0.3
-50.3
this browser
original

audacity
+0.0
-3.5
-5.3
+0.0
-1.1
-9.8
+0.0
-3.0
-4.4
+0.2
-3.3
-5.0
+0.0
-0.5
-9.4
+0.0
-0.6
-9.2
bungee
+0.0
-1.5
-4.9
+0.0
-2.4
-3.5
+0.0
-2.1
-4.1
+0.0
-1.4
-5.6
+0.0
-1.3
-5.9
+0.0
-0.5
-9.8
bungeepro
+0.0
-0.0
-24.8
+0.0
-0.0
-28.6
+0.0
-0.0
-31.5
+0.0
-0.0
-24.1
+0.0
-0.0
-28.8
+0.2
-0.0
-26.0
elastique
+0.0
-4.1
-2.2
+0.0
-0.9
-7.3
+0.0
-0.2
-12.9
+0.0
-0.2
-13.7
+0.2
-1.0
-13.6
+0.0
-0.2
-13.1
paulstretch
+0.5
-27.2
-4.2
+0.0
-24.4
-4.4
+0.2
-31.0
-4.0
rubberband
+0.0
-3.6
-3.4
+0.0
-1.8
-4.8
+0.0
-0.6
-8.9
+0.0
-0.8
-7.8
+0.2
-0.1
-15.8
+0.0
-0.1
-15.3
signalsmith
+0.0
-1.8
-8.2
+0.0
-2.1
-4.6
+0.0
-2.1
-4.6
+0.0
-0.1
-16.7
+0.2
-2.9
-3.5
+0.2
-2.6
-4.1
sonic
+0.0
-0.0
-26.9
+0.2
-0.0
-29.5
+0.2
-0.0
-55.0
+0.2
-0.0
-34.1
soundtouch
+0.0
-0.0
-32.3
+0.2
-0.0
-75.7
+0.2
-0.0
-75.7
+0.2
-0.0
-52.1
+0.0
-0.0
-28.5
+0.0
-0.0
-22.2
superpowered
+0.0
-0.0
-25.7
+0.0
-0.2
-13.7
+0.0
-0.2
-15.9
+0.2
-2.5
-10.7
+0.0
-0.8
-14.3
this browser
original

audacity
+0.0
-3.5
-5.3
+0.0
-1.5
-7.7
+0.0
-2.3
-5.4
+0.0
-2.4
-5.4
+0.0
-2.1
-4.2
+0.0
-2.7
-3.5
bungee
+0.0
-0.2
-11.5
+0.0
-0.5
-8.9
+0.0
-2.4
-3.8
+0.0
-1.4
-5.5
+0.0
-1.5
-5.3
+0.0
-0.8
-8.0
bungeepro
+0.0
-0.0
-24.5
+0.0
-0.0
-23.4
+0.0
-0.0
-27.3
+0.0
+0.0
-28.7
+0.0
-0.0
-22.0
+0.0
-0.0
-30.2
elastique
+0.0
-1.6
-5.3
+0.0
-0.2
-14.9
+0.2
-0.1
-17.1
+0.2
-0.1
-17.2
+0.0
-0.1
-17.7
+0.0
-0.2
-17.4
paulstretch
+0.2
-26.3
-4.5
+0.0
-25.4
-4.4
+0.0
-29.7
-4.9
rubberband
+0.0
-2.0
-4.4
+0.0
-2.2
-4.2
+0.0
-0.7
-8.5
+0.0
-0.9
-7.4
+0.0
-0.2
-14.6
+0.0
-0.2
-13.7
signalsmith
+0.0
-1.4
-8.1
+0.0
-1.8
-4.6
+0.0
-2.0
-4.9
+0.0
-1.9
-4.5
+0.0
-1.1
-7.1
+0.0
-0.7
-9.5
sonic
+0.0
-11.6
-1.0
+0.0
-5.6
-2.5
+0.0
-0.8
-9.7
+0.0
-6.5
-2.6
soundtouch
+0.0
-0.0
-79.1
+0.0
-0.0
-44.9
+0.0
-0.0
-65.7
+0.0
-0.0
-23.7
+0.0
-0.0
-25.6
+0.0
-0.0
-31.7
superpowered
+0.2
-0.2
-18.1
+0.0
-0.6
-12.9
+0.0
-0.2
-16.6
+0.0
-8.3
-6.4
+0.0
-5.5
-6.5
this browser
original

Frequency and transient response

Quantative analysis of frequency response at various settings, response at the low end of the audio spectrum and how implementations handle transients. The transient analysis is based on a comparison of input and output transient locations of music and speech signals.