# MasterChannelGroup & ChannelGroup Question

**URL:** <https://qa.fmod.com/t/masterchannelgroup-channelgroup-question/15757>\
**Category:** Unity\
**Created:** [May 12, 2020, 11:35am UTC](https://qa.fmod.com/t/masterchannelgroup-channelgroup-question/15757 "2020-05-12T11:35:49Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![aprildd](https://avatars.discourse-cdn.com/v4/letter/a/278dde/32.png) [@aprildd](https://qa.fmod.com/u/aprildd)\
**Post date:** [May 12, 2020, 11:35am UTC](https://qa.fmod.com/t/masterchannelgroup-channelgroup-question/15757/1 "2020-05-12T11:35:49Z")

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Hey Guys!  
I’m trying to make a Audio Visualizer in Unity. I wonder if i can add FFT DSP to a ChannelGroup which i get from EventInstance using api getChannelGroup, because when i do this, DSP give me nothing.  
I already know MasterChannelGroup will do the job.But i need to get the spectrum data from another event.Any advise is welcome.Thank you.

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**Author:** ![mathew](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/mathew/32/431_2.png) [@mathew](https://qa.fmod.com/u/mathew)\
**Post date:** [May 14, 2020, 6:31am UTC](https://qa.fmod.com/t/masterchannelgroup-channelgroup-question/15757/2 "2020-05-14T06:31:15Z")

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What you want to do should be possible, perhaps share some code to demonstrate what you are doing and what isn’t working?

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**Author:** ![aprildd](https://avatars.discourse-cdn.com/v4/letter/a/278dde/32.png) [@aprildd](https://qa.fmod.com/u/aprildd)\
**Post date:** [May 14, 2020, 6:47am UTC](https://qa.fmod.com/t/masterchannelgroup-channelgroup-question/15757/3 "2020-05-14T06:47:24Z")

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Thanks for response.I found the error in FMOD.RESULT.I try to get the ChannelGroup during a wrong time when the audio is not completly loaded.Finally I solve the problem by add a EventCallback to the EventInstance.Thus everything goes right.