Metal Oscillator Module
The Metal Oscillator Module is designed to replicate the metal-work of old-school 80's beatboxes.
The oscillator uses a variety of techniques (mostly revolving around frequency modulation and detuned oscillators) to create a series of high frequency partials, which are meant to mimic the partials created by hitting a cymbal or hihat.
Working with the Metal Oscillator
The metal oscillator creates frequencies across the entire spectrum, so it is important to send it's output through a high-pass filter, or through an equalizer that can remove lower frequencies.
Aside from that, the best technique for getting good sounds, is just to play around with the parameters until you find something you like.
Of the three modes included in the oscillator: Exp is good for hi-hats, MD1 is good for ride cymbals, and MD2 is good for 808-inspired sounds.
Modes and Parameters
Each of the modes in the metal oscillator have their own sets of parameters. Because of this, the oscillator will be reset when you switch between modes.
Exp is for experimental. Exp started out as a test, but eventually became ingrained into the metal oscillator. This mode features three sets of square wave oscillators. Each set contains a modulator and a carrier. The modulator frequency modulates the carrier, and the carrier's signal is sent to the output.
The 'PModulator' parameter controls the pitch of the modulator. The 'PCarrier' controls the pitch of the carrier. The 'Volume' parameter controls the volume of the carrier as it is sent to the output. These parameters are repeated three times, once for each set of oscillators.
The 'FMAmount' parameter controls the amount of frequency modulation being applied to each of the carriers. The 'FMSpread' parameter offsets the amount of frequency modulation being applied to each carrier, so they are not all the same. The purpose of these two parameters is to be able to spread partials across a large spectral range.
The 'Pulsewidth' parameter controls the pulsewidth of both the modulator and carrier oscillators. The metal oscillator is much more effective if this parameter is near (but not directly at) it's highest or lowest value. The 'PWSpread' offsets the the 'Pulsewidth' parameter between each oscillator set, so they are not all the same.
MD1 is similar to 'Exp' but creates a smaller range of partials. The end result is a more 'pitched' sound which is similar to a ride cymbal. The pitch values in this mode also have a larger range.
The 'PModulator' parameter controls the pitch of the modulator. The 'PCarrier' parameter controls the pitch of the carrier. The 'FMAMount' parameter controls the amount of frequency modulation that is applied to the carrier. The 'Volume' parameter controls the volume of the carrier as it is sent to the output. There are three sets of these parameters, amounting to three different oscillator sets.
To fill out the sound produced by this mode, it's helpful to use the white noise option, as described in Module Specific Options.
This mode duplicates the voicing architecture of the TR-808 made by Roland. The 808 used six square wave oscillators to generate metallic noises. The theory was that when passed through a high-pass filter, the remaining signal would have a reasonable amount of high-frequency partials.
The 'Pitch OPX.1' parameter controls the pitch of the first oscillator. The 'Pitch OPX.2' parameter controls the pitch of the second oscillator. The 'Pulsewidth OPX' parameter controls the pulsewidth of this oscillator set. The 'Volume OPX' parameter controls the level of the oscillator set as it is sent to the output. There are three sets of these parameters, amounting to three sets of oscillators.
The 'Volume White' parameter controls the level of the white noise as it is sent to the output. You must have the white noise option enabled for this parameter to have an effect. See Module Specific Options.
Module Specific Options
The 'Exp', 'MD1', and 'MD2' buttons switch between the three different modes outlined above.
Each mode has three sets of operators. The 'OP1', 'OP2', and 'OP3' buttons control which of the operators are currently active.
In Exp and MD1 Modes: The 'Wht' button will replace the third operator with white noise. The volume control from the third operator controls the volume level of the white noise.
In MD2 Mode: The 'Wht' button will add white noise to the output. The white noise has it's own volume control.