pan law needed; suffering from loudness bump

brendan mccloskey's icon

Hi
I am using the phase inlet of two cycle~ objects to control stereo-spread of a sound source, but it appears I am missing some maths.....it functions ok, but there is a slight increase in loudness when the slider value is near the centre, tapering off at either min or max value; the patch below illustrates the problem. I would like to achieve a stable and uniform loudness level across the parameter range, from mono to stereo.

Max Patch
Copy patch and select New From Clipboard in Max.

thanks
Brendan

brendan mccloskey's icon

Apparently ignorance IS bliss.....I swapped the phase-inlet control for a simple line ramp, to control the amplitude scaling of the channels and the loudness bump is gone

Steven Miller's icon

Would you mind posting a patch showing your solution? I'd love to see it - I don't quite follow your explanation, but it sounds useful. Thanks!

ehdyn's icon

If you look here on page 74 it should help http://aspress.co.uk/ds/pdf/pd_intro.pdf

brendan mccloskey's icon

@ehdyn
thanks for the great source; very 'layman' friendly!

@Steven
Sure, this patch illustrates how curved and straight line scaling of amplitude effects panning and also "stereo spread" to some extent, but in this example patch I just have a simple mono source going both left and right. But in my granulator it works like a dream......yummy stereo multigrain goodness!

Max Patch
Copy patch and select New From Clipboard in Max.

Brendan

Steven Miller's icon

Thanks Brendan, much appreciated. I understand the general concept of "pan law" and have used various implementations - I just didn't follow the specifics of the explanation in your original post.

ehdyn's icon

Cool, glad it helped - yeah thats a good resource.
That site and an old emu manual is all anybody really needs.