@trummerschlunk Have you tried using FFT resynthesis? The bands won't have constant pitch width and the whole thing will introduce extra latency, but it might not matter depending on the sound you want. Take a look at I06.timbre.stamp in Pd help. Also, the min number of bands would be 256, so you'd need to combine bands to get down to 32.

@trummerschlunk If you don't feel like figuring out the math, you could instead convert your end frequencies to fractional MIDI note numbers using [ftom], divide that MIDI interval into the number of bands you want, then convert back to frequency using [mtof]. That'll calculate the log stuff for you.
center frequencies.pd

@rph-r I don't know WebPd and will let others advise you on the networking issues, but you could easily make a remote UI for your installation patch using netsend/netreceive because by default they support Pd list messages:
server and remote.zip

@melter In your first post you wrote "distance between distance 1 and distance 2" but now you're writing "d1 and d2 (which controls the volume of the sound) is zero". In Pd, division by 0 equals 0 (which is definitely weird IMHO)--is that what you meant?

If you're not making the assumption I think you are, then why are you computing the difference between the log math and the output of [env~] in [inverse_sq_law]?

Why is it not enough to just divide distance 1 by distance 2 (both non-zero) and take that as your RMS factor? e.g.

Edit: I cross posted with @manuels ... didn't intend to repeat what he wrote

@melter I think you are expecting [env~] to output 100 for [noise~] at full amplitude. The approx 5dB discrepancy appears to be from that. Take a look at the [env~] help--even for a full amplitude sine, the output is -3dB.

@ddw_music Is this what you're looking for? It's from [pd [expr] examples] in [expr] help.

@le26muko said:

My bandmate is pushing me to sell it

On occasion, someone has seen something I've made for myself or for a work-for-hire job (e.g. a bike chain sleeve, a tube circuit, or an escape room feature) and has encouraged me to create a business selling it. I"ve offered these folks 50% of the company if they'd just help me set it up and navigate all the business stuff. So far, no takers, which to me is very revealing.

Last update:

QLab tech support reproduced the error in QLab but reported that it doesn't happen in Ableton Live. They also discovered the following workaround:

We found that it's possible to persist the settings for a QLab cue with
an extra step. After configuring the effect settings as you'd like them, 
save them as a user preset for that AU. Then load that user preset, and 
the configuration will persist even after stopping and reloading a cue, 
and after saving, closing, and reopening the workspace.

That sounds like what I did in that one case, and it makes sense because (duh) saving a preset saves the current patch state. Figure 53 (QLab's maker) doesn't have the resources to investigate further, so can't provide any more insight. @timothyschoen, would it be helpful I entered this issue into plugdata's github or is that redundant?

@ddw_music said:

FWIW I can't get Audacity to use plugdata-fx -- I've enabled it in the plug-in manager, but it still doesn't show up in real-time effects for a track.

Weird. I got nuthin for you. I installed Audacity 18 months ago, maybe updated it once or twice, and just recently installed plugdata. Wasn't even aware of the plug-in manager.

Update: I decided to skip the QLab group and submit a support ticket. I figure it's paid software, so why not?

@dreamer said:

So the problem you see with Qlab is that a saved project does not retain the plugdata state? or was it that simply closing the plugdata window resets its state somehow?

Well, both, but I would expect the former to fail if the AU forgets its state before you can save in the host. In QLab and Audacity, plugdata reverts back to its initial state (no patch loaded) in the course of normal host operations, before I've attempted to exit. I think I even tried exiting QLab while the cue and effect were running (and was prompted to save), but I'd have to rent another day license and check (which I'll do once I learn a enough about Cardinal to construct a useful test).

Hmm, but hold on a second. @ddw_music - if I somehow managed to save once in QLab (see the first paragraph of my original post), then doesn't that mean the huge plug-in state size hypothesis can't be true?