Underrun Detected: 3 blocks dropped :( (pd on bela)

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Underrun Detected: 3 blocks dropped :( (pd on bela)

majedbg

Hello ~ I'm a little new to bela, I usually run PureData stuff on my laptop. I'm getting the underrun error 10 times a second and also "Your code is printing to the console too quickly. Check your audio thread for print messages." which I presume are related. Any idea how I can fix this? I am getting clippy playback

If the pd patch is hard to read, what is basically happening is the mic in is being recorded into 'mumble' (when threshold is met), and then replayed (after a delay) and fed into a vocoder, where the pitch is controlled by a random melody generator, with some variation in note duration.

second screenshot is vocoder

alt text

giuliomoro

majedbg "Your code is printing to the console too quickly. Check your audio thread for print messages."

ignore that one

majedbg I'm getting the underrun error 10 times

this is the important one.

you have [block~ 1024 2], which means you are performing one FFT every 512 samples. So you need to change the block size in the Bela project settings to 512 accordingly.

majedbg

giuliomoro

Perfect! I didn't think it would be the FFT, thank you for replying quickly as well!

Another question ~ just curious: the 1024 block is doing doing fft every 512 samples and not 1024? is it related to the nyquist freq /its sampling double for a resolution of 512?

giuliomoro

majedbg Another question ~ just curious: the 1024 block is doing doing fft every 512 samples and not 1024? is it related to the nyquist freq /its sampling double for a resolution of 512?

no, it's because in [block~ 1024 2], the 2 means "double overlap", which - if I understand correctly, as I find the [block~] help file is confusing - means that each [fft~] will be executed in blocks of 1024 samples every 512 samples, with what is otherwise called "50% overlap" or "512 sample step size"