Clock phase control?

I think ppl here are being overly literal, but whatever…

To quote from the Organ 3 manual “Like a real organ, Organ-Three sounds really good when processed by a “Leslie” effect. The Surge Rotary is a very good one, although there are probably others.”

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Haha…you are right! At least for the most common model.

From the Wiki page:

Different models have different combinations of speakers, but the most common model, the 122, consists of a single woofer for bass and a single compression driver and acoustic horn for treble.

Yeah and just for completeness, the essence of the Surge rotary is

  1. Figure out a stereo pan field position left/right for the spinning horn
  2. Sum stereo to mono
  3. If drive is active, pass that mono to the overdrive circuit
  4. Run a high crossover into “upper” and “lower”
  5. Delay the “upper” by the doppler amount adjusted left/right by the spinning horn
  6. Run a low crossover on “lower” into “lower” and “lower sub”
  7. Use the rotor LFO to tremolo lower
  8. Make final signal delayed upper + tremolo lower + unaltered sub
  9. Apply the standard surge width calculation (Stereo/MidSide → Scale side up → MidSide/Stereo)

So you could just construct an equivalent with a few filters lfos the surge tuned delay or any other sample accurate short delay and a drive of your choice with modules from first principles and get a similar sound.


Interesting. So the rotating horn simulation is “just” a doppler and no other frequency shaping? Wow, it sounds so good! (I don’t think you mentioned all the distortion models built in, too.)

Well doppler only on the bit from the top of the crossover so that’s an implicit high pass before doppler but yeah from reading the code looks that way

And indeed plenty of drive models. But they are all in the surge waveshaper module if you wanted to try and first principles recreate it

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