Behringer Kobol Expander Patching Tips

In analog synthesis, a Voltage Controlled Oscillator (VCO) is an oscillator whose output frequency is determined by an input control voltage1. The frequency (pitch note) and amplitude (the power of the signal) are often modulated directly by the synth’s keyboard.
The term “beat frequency” in this context typically refers to the phenomenon that occurs when two VCOs are operating at slightly different frequencies. The resulting sound fluctuates in volume at a rate equal to the difference in frequencies of the two VCOs. This fluctuation, or “beating,” can be used creatively in sound synthesis to add richness and depth to the sound.

[@nach_keyboards]

Definitely one of the most instructive video I've seen about that instrument so far . Very interesting tips. Thanks!

[@kezstone1]

The info on how to patch the noise out and have independent volume control over it is awesome, thank you. you can also patch the noise 'out gain' into vcf frequency or resonance for great distortion effects too.

[@simoningate2056]

Nice video. The beat frequency is just a fine tune on osc2 - so it gives (if value is small and both oscillators were at same frequency) a slight detune which thickens up the sound. This is found on most synths. The beat frequency is what moog calls it (for example on modern stuff like the Sub37). That narrow pulse wave is great for guitar and string sounds (got a really nice Cello type sound out of it). I am going to patch this up to my B2600 since you can effectively have 4 LFOs from it - could be pretty interesting.

[@THEREALDATALORD]

VCO 1 and VCO 2 have their own dedicated FREQUENCY knob in addition to the VCO 2 BEAT. The best description I found was "The term “beat frequency” in this context typically refers to the phenomenon that occurs when two VCOs are operating at slightly different frequencies. The resulting sound fluctuates in volume at a rate equal to the difference in frequencies of the two VCOs. This fluctuation, or “beating,” can be used creatively in sound synthesis to add richness and depth to the sound."

[@THEREALDATALORD]

I think it's used for tuning VCO 2 when Oscillator Sync is enabled also.

[@simoningate2056]

@@THEREALDATALORD Yes that is correct.

[@cnfuzz]

Lot's of drawbacks in the signal routing of the original design , other synths solved this more elegantly , for instance i assume both lfo shapes can't be tapped simultaniously , is the vco frequency low enough to use as auxilary lfo?

[@simoningate2056]

Have you tried using the envelopes (I guess via the voltage controller) to control the amount of noise added to a patch. I have been experimenting but it does not seem to work.

[@josephjonzen9394]

Incredibly helpful. Thank you! Any thoughts on the tuning? I heard the Model D was a little bit off in higher octaves.

[@josephwright5921]

Let us hear it more, please! 😢 Maybe you could do am extended jam alongside a drum machine 😊

[@JoseAngelMorente]

"Proton CV yellow".... hmmm.

[@terrancehiscock4085]

Been waiting for a Proton.
Looks like it's being tested
😁