# Speed up the audio but don't alter the pitch

**URL:** https://qa.fmod.com/t/speed-up-the-audio-but-dont-alter-the-pitch/15367
**Category:** Unity
**Created:** [January 8, 2020, 12:36pm UTC](https://qa.fmod.com/t/speed-up-the-audio-but-dont-alter-the-pitch/15367 "2020-01-08T12:36:51Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![kantagara](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/kantagara/32/1666_2.png) [@kantagara](https://qa.fmod.com/u/kantagara)
#### Post date: [January 8, 2020, 12:36pm UTC](https://qa.fmod.com/t/speed-up-the-audio-but-dont-alter-the-pitch/15367/1 "2020-01-08T12:36:51Z")

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So I’ve bumped into this topic for the potential answer  
[https://qa.fmod.com/t/changing-pitch-in-fmod/10578/3](https://qa.fmod.com/t/changing-pitch-in-fmod/10578/3)

but as far as I can see DSP is something that’s the same for all the tracks. What I need is that when I write `fmod_event.Play2D(PlayParams.Speed(speed).AndDelayFracOf(anim_duration)` to somehow add that FMOD\_DSP\_PITCHSHIFT for that event only. Is that possible?

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### Author: ![cameron-fmod](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/cameron-fmod/32/261_2.png) [@cameron-fmod](https://qa.fmod.com/u/cameron-fmod)
#### Post date: [January 14, 2020, 4:28am UTC](https://qa.fmod.com/t/speed-up-the-audio-but-dont-alter-the-pitch/15367/2 "2020-01-14T04:28:09Z")

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A DSP, in this case [`FMOD_DSP_PITCHSHIFT`](https://fmod.com/resources/documentation-api?version=2.0&page=core-api-common-dsp-effects.html#fmod_dsp_pitchshift), refers to an [effect](https://fmod.com/resources/documentation-studio?version=2.0&page=fmod-studio-concepts.html#effects) that can be added to a Channel, Event or Bus.

[https://fmod.com/resources/documentation-api?version=2.0&page=white-papers-dsp-architecture.html](https://fmod.com/resources/documentation-api?version=2.0&page=white-papers-dsp-architecture.html)

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### Author: ![Bradgentle](https://avatars.discourse-cdn.com/v4/letter/b/898d66/32.png) [@Bradgentle](https://qa.fmod.com/u/Bradgentle)
#### Post date: [January 14, 2020, 5:50am UTC](https://qa.fmod.com/t/speed-up-the-audio-but-dont-alter-the-pitch/15367/3 "2020-01-14T05:50:11Z")

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You can do this in the timeline, but it only works to a certain extent. I’ve found its better with speeding up a sound rather than slowing it down, so make sure the original is the slowest you want it to be.

-Firstly, add the pitch shifter effect to the channel you want to affect.

-Secondly, check the image and choose one of the “pitch effect” column values and put that into the Pitch Shifter’s “pitch” knob.

-Then, on the timeline clip itself, change the clips pitch value to be the opposite value than the "pitch effect you put on the pitch shifter’s channel.

-NOW, Automate the values on whatever parameter you would like to have the unaffected value at one end , and your new sped up version at the other end.

[![Imgur](https://i.imgur.com/h4821Mm.png?fb "Imgur") ](https://imgur.com/h4821Mm)  
Here’s an image of the pitch values that correlates to whole pitch changes. (Click it to see the proper size iIguess)  
The actual formula for working out the pitch effect change is …=2^(PITCH SHIFT AMOUNT/12)

Hope this helps.