Pitch issue at 48kHz - Githubissues

MikeMorenoDSP / EP-MK1

EP-MK1 is a real-time physical model plugin of an Electric Piano built with Pure Data and Camomile.

GNU General Public License v3.0

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Pitch issue at 48kHz #3

Open sub26nico opened 4 years ago

sub26nico commented 4 years ago

It seems the pitch is not good if I set my audio server (JACK) at 48kHz. The pitch is too high by more than a half tone. Setting 'Base MIDI' to 70 and 'Base' to 428.5 can resolve it but it is not very user friendly. No problem at 44100Hz. I use the last release (EP-MK1 v2.2) linux version on Debian Buster.

alexandregaldeano commented 4 years ago

It seems the render depends on the sample rate, here is why I think the suggested workaround works:

44.1kHZ/48kHz = 0.91875
MIDI 70 = A#4 = 466.16Hz
466.16Hz x 0.91875 = 428.2845Hz ~ 428.5Hz

But it would probably also work without changing the base MIDI and set the base A4 to 404.25Hz. So my guess is that if you work at a sample rate of X kHz, change the base A4 to (440 x 44.1 / X)Hz. However, you would also need to multiply every time-based parameters to 44.1 / X.