I was asked about how to make a Hammond patch, so here is a small tutorial:
The basics:
The base Hammond sound consists of nine sine-like wave components that are mutiplicants of the base wave (the base note). A volume of each component is controlled by a drawbar and this is a way you make different wave combination thus getting a divverent tones and sounds.
So how the sound components go then? Let's take a look:
Every drawbar is named after a lenght of a pipe that the component would present in a real organ. So the lowest component (drawbar) is named 16' and the highest 1'. You really don't do anything conretical with the info how long the pipe would be, it's just that if someone mentiones "2 2/3' drawbar" you know what it's all about.
If you press a middle C (C3), you'll get the following tone frequencies (notes) on the drawbars:
16' - C2
5 1/3' - G3
8' - C3
4' - C4
2 2/3' - G4
2' - C5
1 3/5' - E5
1 1/3' - G5
1' - C6
The base sound:
By that chart above you can pick the drawbars you want to use in your Hammond patch and create a simple patch (or set of patches) that have the desired transponsed waves.
For example if you want a sound that has three first drawbars, you create a patch that has waves that are transposed to -12, +7 and 0 semitones. Then just set the component volumes to suit your taste.
For a component waveform I'd recommend basic sine wave, but as the Hammond sound is not a pure sine (it's a bit round instead) you could set filter keyfollow to +32 (or what ever the value is on TI that links the filter frequency to the note frequency) and try to LP filter a square wave to almost-like-sine. I don't believe there is a much difference, but tweaking is always fun.
Also note that all the components are synced to eachother, so no free running oscillators here.
You can add abit vibrato for pure Hammond vibrato or some fast LFO'd extreme chorus for the Hammond chorus vibrato.
Clickety-click:
The essential part of a Hammond is the click. Click is a short amp envelope that causes a pulse of either 8' of 4' tone (C3 or C4). The tricky part with emulating the click with Virus is that the Hammond click is not true monophonic, but not true polyphonic either.
The click envelope is triggered when there is no notes playing and you press a key(s). This is ok, but the problem is that the click sound should contain every note pressed - For example if you play C7 chord the click should contain all the notes from the cord isntead of like the base C, like in true monophonic. It's like a monophonic amp envelope after the actual patch. I didn't find a way to produce this on my Virus kB so I stick with a true monophonic click. I'm not sure how much the TI's architechture has changed from the B/C-series, but there could be a way to generate a global patch amp envelope.
The click patch is easily done. Just make an organ patch with a single 0 or +12 transpose wave and set a short amp envelope for it. Remember osc synchronisation! That's it.
Key-click:
More clicks. Yay! The key-click is a sound that is caused by the key connecting to the drawbar shafts. So it's a "malfunction" sound that's caused by the keyboard mechanism. The key-click increases when the organ gets older and even it's not a desired phenomena, some people (like me) like to have some key-click.
To create a key-click patch, just make a white noise patch, set in some distortion and set the amp envelope to real fast. The key-click sound should sound like ultra short "zip". (Note: Key-click is polyphonic)
The leakage
Sometimes the drawbars "leak", especially on old Hammonds that are not in as good shape as they could be. The leak is a faint drone sound that's played on a background of the notes. The leakage consists of all components the organ generates. This is why it sounds like white noise, but it's not even close white noise.
The best way to generate a leakage sound is to fiddle with heavy set of sinewaves and ringmodulation with some white noise and distorion. As it should "hiss" a bit hollowly you could try to add a paraller distorted BP filter with rather high resonance to give some more hiss. Set the keyfollow of the oscillators to 0 and the patch to monopohnic as the leakage is not affected by which key is pressed and how many notes are playing.
The leakage sound is an area I can't really give any exact orders. You'll just have to find a combination of the ingredients above to get a good drone.
But if you don't manage to generate a good result, don't worry - the leakage is not an essential in any way as it's mixed hardly audible. You could try to make it if you feel like tweaking is your business.
Mixing the patches as Multi:
This is easy. Start by piling up the base sound patches to suit your taste. Then add the click, next the key-click and finally the possible leakage patch to the as much background as you can. There you should have a good raw Hammond sound.
Polishing up:
The thing that makes the Hammond sound is the leaslie speaker. To get the good resluts, drive the patch through an amp simulator and/or leslie simulator. If you don't have that opportunity you could try to simulate it on Virus. Route the every patch of the multi to a one channel that works as a FX unit. Set in some distortion and slow slight stereo chorus. Also set a slight pan LFO if possible to match the chorus LFO. From the modulation matrix set the ModWheel to control the chorus LFO frequency and the possible pan frequency. Then add rich room reverb and voil
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