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Spat5.conv~ for spatial reverb


I am a bit confused when it comes to using the Spat5.conv~ I wish to create a spatial reverb. Let’s say I have 4 IR’s in different directions in a room, and then playing back that 4 directions on virtual VBAP sources on the system. How best to approach this?

Greetings, Marijn

hi marjin,

i think you should start over, buy a cheap multichannel mike like zylia, and convolve its result with spat5.conv~ as a multichannel file input. You can even use the encoded hoa of the zylia recording which will offer you much more flexibility to use that IR, and decode it for any restitution system.

Otherwise, you can try to create an interleaved file with your 4 IR takes, and use it as the IR input of the spat5~conv, but depending on what you are looking for, it might sound very experimental. As i said, could be also fun.


Hi Marijn,

It’s not easy to answer, because it strongly on depends on

  • the format of your available IRs
  • the speaker layout you want to use
  • what you mean by “create a spatial reverb”

Can you describe more precisely your use case ?


Hi Thibaut, thanks for the reply. Forgive the vagueness of this question.

I want to do the following:

Create an IR response in 4 directions (4 channels), not encoded, just 4 directions.
Play back the IR convolution reverb over 4 vbap3d sources (regardless of speakersetup

My question: How do I need to configure my spat5.conv~ object to play back this 4 IR’s correctly?

I hope this makes it a bit more clear.

Greetings, Marijn

Additionally; would it be more beneficial to use a HOA encoded IR signal?

Sorry, but it’s still unclear.
What do you mean by “4 directions” ?
An IR captures the acoustical response between one emitter (with a given position and orientation) and one receiver (with a given position and orientation); so, it’s unclear what “directions” refers to in this context.
There is nothing to configure in spat5.conv~. The object really just performs the convolution of an input signal with an IR (regardless of what that IR “contains”)