The B3 itself lets a player adjust the harmonics of the sound on the fly, shifting from a thick meaty sound to any number of thin reedy or subdued sounds with a single half-instinctual shove. The B3 is all over the place, from gospel to rock to radio plays. You’ll know it when you hear it even if you can’t name it.
And the Leslie. Oh, the Leslie. I heard it referred to as “a uniquely American design,” with a woofer aimed downward at a curved wooden wedge and a treble horn for the high frequencies, each piece rotating in opposite directions, throwing sound around a room and affecting the volume and frequencies of the organ in pleasing and interesting ways.
Lots of people have spent lots of time trying to recreate this sound in software, with varying degrees of success. My favorite example (real or simulated, I don’t know) is in Portishead’s “It’s a Fire”, since the organ is the main instrument and they put it through its paces: flipping the Leslie between its fast and slow modes while pulling the drawbars, and the tonal structure is wonderfully complex as well.
I think discovering the mechanics of these two things in tandem was part of what sparked my love of synthesizers and how they can be used to create and shift musical moods. The tools are a bit different but the fundamental idea is very similar.
But the corresponding control for each drawbar on the Hammond is basically a binary switch instead of a quasi-continuous control.
Further each individual pipe has its own harmonics and timbre while the Hammond tonewherls produce nearly (but not exactly) sinusoidal waveforms.
Fancier pipe organs had multiple pipes at each harmonic. Eg, pipes that mimicked brass or woodwind instruments. This is why pipe organ consoles can be huge and cluttered with tons of switches. The Hammond simplified all that and let you adjust harmonics directly with a quasi-continuum via the drawbars.
With the onset of jazz and rock in the 60’s, the Hammond’s unique sound became highly sought after. The so-called “Hammond Growl” through its tube amps, it’s own analog chorus and vibrato unit, the external rotating Leslie speaker’s effects, and even the “key click”.
When the 70’s came along, pop tastes shifted to newer synthesisers and the last of the B3’s from the assembly line languished at organ dealers.
The best sounding commercial keyboard to emulate the B3 IMO is the Nord C2D/C2.
These two instruments are both great, but the Hammond is no analog for a pipe organ. Neither in tone nor the way it interacts with room acoustics. It's fascinating that this could even be a plausible discussion.
You can improve your hearing markedly with practice. I didn't start with "golden ears" but have improved a great deal even as my ears age. But many of my worst days behind a mixing desk got the most positive response from the general audience.
Unless you're in music production, learning "how bad things sound" doesn't sound like a good thing.
There's still a lot of room for art in the process, though. With experience you get less attached to your particular sonic leitmotifs, and that helps. Even if you would not personally mix it the same way.
You can easily imagine someone furiously playing a cello when listening to a lot of death metal, especially Swedish death metal with the classic Boss HM-2 pedal sound.
They didn't really get it, and most of them are pretty big fans of Apocalyptica, who very specifically play heavy metal on cellos. Still, they didn't make the same connection, which made me wonder if my hearing is a bit odd.
What do you mean with golden ears? Do you mean perfect pitch? The ability to hear what is not intended by the sound source to be there?
Things you can train for include: being sensitive to minute changes in level/frequency/time, picking one source out of many, precisely placing items spatially in stereo, listening for specific types of audio artifacts.
Golden ears could include perfect pitch, but in the production context pp might be translated to a specific frequency, rather than a note.
I don't know what rock I've been living under, but that's the first time I've heard the brain referred to as a 'meat computer'. What an image! In any event, a quick search surprisingly didn't turn up any Wikipedia page, bit mostly pages (e.g. 1) denouncing the idea of the brain as a meat computer, associating it with the flailing concept of phrenology (designating regions of the brain as controllers of specific tasks).
I'm not a neuroscientist, but based on all of the pieces of evidence describing brain function I've consumed over the years, it seems obvious to me that the meaty neurons brain to appear to be 'computing'.
Or rather, we who have decades of experience in this field, have over average capacity for processing music and the sounds/patterns we have studied/practised. Then again, that is true for every field.
I do not however, believe "most people" (with less developed hearing) are relevant to why this "battle for the organs", came to be.
It helps to really look deeply.
When Hewlett & Packard were strongly involved with the design & production of their legendary instruments these were some of the most well-designed, advanced, high-performance, purpose-fulfilling, and amazingly reliable long-lasting electronics in history.
When Hammond was strongly involved with his it was even better.
I've got a Hammond amplifier built in 1948, sounds like heaven.
There's no need to repair or replace any components yet since it's only 2019.
Seemed inspired like Edison or DaVinci.
And a benevolent capitalist not a greedy one, after starting a growing company based only on an insignificant amount of one's potential IP there can be a lot of confidence when there's plenty more where that came from.
Chapter X - The Tickless Clock, Teleview, and the "Classified" Patent
Of course that was in the days before transistors ... and so it used 163 vacuum tubes (and 1000 capacitors). VCAs, bandpass filters, LFOs and on.... Only 1000 were made before the war shut down production; there are only a few dozen left it seems.
I think Martino is still touring. His 70s jazz-fusiony records were amazing. My favorite are probably his post-break records in the late 90s. Those licks are impossible to play. And forget about improvising that way...
 - https://www.youtube.com/watch?v=uhFIupVoVKc
 - https://www.youtube.com/watch?v=oyJJltEhvkc
Al Kooper "like a rolling stone"
Miles Davis/Cedric Lawson "rated x"
and of course, "green onions" Booker T and the MGs...
Instruments with dynamics - not a pipe organ, unless you include the swell pedal or some of the dynamic effects, like tremulant - the spectrum also varies with dynamics.
So generally, no, you can't accurately reproduce a sound with a single plot of the harmonics.
I'm more curious about how the physicist worked out a spectral plot by hand before sampling and FFTs were invented and oscilloscopes were barely a thing.
I'd guess he sketched the waveform from a scope plot, broke it down into points by hand, and performed a manual DFT - which must have taken quite a while.
Also - you can reproduce a sound by the frequency domain IF you look at the time progression of it.
Some Hammond Organs intentionally had a percussion control where the 3nd or 3rd harmonic would decay over time, giving the instrument timbre a bit of a pop.
Before there were digital FFTs, there were analog equivalents. A prism basically does an FFT on light. I don't know, but I'd bet there were many analog based frequency analysis tools available before digital frequency analysis.
In the case of the Hammond, it seems to be mostly by accident. They were just trying to create a cheaper version of a pipe organ, in effect.
The tone wheels made it possible.
The drawbars allow changing the timbre in a lot of ways, which makes the instrument expressive and configurable. You can adjust the timbre while playing a note! Sort of like using a mute on a trumpet, only more combinations.
The keys make a satisfying percussive click when played, which is also expressive. A Hammond player told me once this click was not intentional (the designers viewed it as a bug), but it helps give the instrument a nice attack, which helps make the starting of the notes apparent to the listener and allows the instrument to be used rhythmically.
The Leslie rotating speaker was an attempt to create some of the acoustic ambiance of pipe organs. (Which is amazing, by the way. The instrument literally surrounds you in some cases. It's like centuries-old surround sound. Not to mention the rich acoustics of a church hall, which is built to encourage reverberation so that the audience could hear an orator in the days before amplification.) But the Leslie speaker's rotation adds not only spatial effects but also doppler. And the speed of rotation can be changed, so you can make the sound tenser or more mellow by varying the speed. So it's great for expression as well.
Incidentally, a lot of other instruments achieved greatness by accident. Resonator guitars (Dobro, National Guitar, etc.) were made in an attempt to get more volume, but they ended up having a unique sound. Electric guitars were made for more volume too, but they opened up an entire new world of tones, as well as different playing styles due to lighter strings. The stereotypical distortion effect on electric guitars (that give them their aggressive "bite") came about because guitar amplifiers just didn't have enough power. The vocoder was developed for speech synthesis and telecom, but it found use in music as a way to give a radically different timbre to a human voice. (Or is it to modulate another instrument's sound to follow the volume of a human voice? Maybe those mean the same.)
Coincidentally, I just recently discovered Marcin Grochowina's channel YouTube, where there are several nice Rhodes videos: