For Musicians
Editing Instruments
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Editing Instrument parameters is usually quicker and easier than editing the underlying Samples themselves. In addition, creating Custom Instruments (as opposed to custom Samples) has a negligible effect on user download times. We would encourage you to experiment with Instrument editing, even if you aren't creating your own Custom Samples.

Note: You can only edit Custom Instruments, not the Built-In Instruments. You can create new Instruments from scratch, or copy built-in Instruments to the Custom bank, then edit them. Instruments can be copied and pasted (or dragged and dropped) between Sessions.


The Instrument Editor has five Pages:
Heading...
Covers...
Keymap
Assigns specific Samples (built-in or custom) to ranges MIDI notes
Filter
Sets the peak frequency spacing and resonance used by Beatnik's comb filter, and the tone control
Volume
Controls the amplitude envelope applied to each note
Output
Sets the Instrument's position in the left-right stereo mix
Modulation
Defines up to five modulation sources to further manipulate an Instrument's sound


Keymap


The Keymap Page defines which Samples are played across an Instrument's keyboard. As a Sample is played further from its original pitch, transposition artifacts become more apparent. So, modern samplers and wavetable synthesizers use multiple samples to create a single Instrument. For instance, a piano could use half a dozen samples originally recorded across a range of pitches. An Instrument can contain from 1 to 128 of these zones.

See also: Keymap Page in the Instrument Editor window section.

Filter


The Filter Page is the second block in the signal path. Each Instrument can use its own Comb Filter and tone control. The Comb Filter has both peak frequency spacing and resonance settings.
In general, the Filter can liven up the sound of an Instrument, as well mask aliasing or noise in a Sample. The only drawback is that each Filter uses some CPU power, particularly when its resonance is turned up. When you have a Song that uses a lot of Instruments with Filters, keep an eye on the CPU Load meter in the Player window to make sure it's performing within acceptable limits.
The most important Comb Filter setting is its peak frequency spacing. A comb filter has multiple, fixed peaks evenly spaced across the frequency spectrum. Frequencies in between the peaks are turned down, removing those components. Peak frequency spacing can be set to a fixed frequency from 175 to 11,200 Hz. The sound will get progressively brighter and duller as you play across the keyboard from low notes to high notes, depending on how wide the spacing is.
There is an alternate to a fixed frequency spacing: The Track Pitch option causes the filter frequency spacing to increase and decrease as the pitch of the played notes goes up and down the keyboard. When Track Pitch is enabled, you can allow all notes to have a similar tonal character.
Another important filter control is Resonance. Resonance creates a hump or frequency boost centered around the cut-off frequency. The higher the resonance setting, the more audible this hump becomes. The resonant frequency will follow behavior of the cut-off frequency as described in the Track Pitch option.
In addition to the Comb Filter, there's also a Tone Control - a gentle high or low frequency rolloff filter with a Depth setting:
  • When the Tone setting is positive, the Tone Control rolls off high frequencies.
  • When the Tone setting is negative, the Tone Control rolls off low frequencies, and the Comb Filter is bypassed.
Note that you have the option to dynamically sweep any or all of the continuous filter settings (comb filter frequency peak spacing and resonance, and tone control) - see the Modulation section.

See also: Filter Page in the Instrument Editor window section.

Player Sample Rate and Filter Frequency

Note: An Instrument with prominent filtering will sound significantly different depending on whether the listener's Beatnik playback software is operating at 22kHz or 44.1 kHz.As a result, you should set the Player window playback settings to the same sample rate as the playback system where you plan your music to be played. For the Beatnik Player for Web browsers, this is 22kHz. For the Beatnik Xtra, JavaSound, or the Beatnik Audio Engine, check with your programmer to see what sample rate they intend to use. As you work on your Instrument in the Beatnik Editor, you may want to listen to your song at a number of different sample rates, evaluate the sound character of each.

Volume


The Volume Page contains a flexible Envelope Generator that controls the attack, sustain and release levels of each Instrument's sound. These levels are shown as an editable, graphical curve defining the note's overall volume contour over time.

See also: Volume Page in the Instrument Editor window section.

Output


The Output Page is the simplest part of the Instrument editor. Here, you can set the Instrument's default Stereo Pan position. You can also disable reverb for the Instrument.

See also: Output Page in the Instrument Editor window section.

Modulation


Modulators can make an Instrument more dynamic and interesting, but they make no sound of their own. Instead, they work by changing (modulating) various parameters of the instrument dynamically in real time. Parameters like volume, filter settings, or pitch can be modulated by low frequency oscillators (LFO's) and envelopes. You may have up to five simultaneous modulators per instrument; it's also OK if your instrument doesn't use any.

See also: Modulation Page in the Instrument Editor window section.

As you may know, modulation is a two-part proposition; each modula-tor controls a modula-tee, if you will. Beatnik has four different types of modulators, and six different Instrument parameters can be modulated.

Modulator Destinations

Volume

Modulating the volume of an instrument creates a fluctuation in the Instrument's level. Those familiar with the classic guitar amplifier tremolo effect will know exactly how this sounds.

Pitch

Normally, an Instrument's pitch is controlled by the MIDI note being played, and the pitch bend wheel (if used). Applying a modulator to the pitch of an Instrument will add a pitch vibrato, warble, bend or other gesture to every note played.

Stereo Pan position

There are three ways to adjust the stereo position of an Instrument's sound: The Stereo Position setting in the Instrument Output tab, the use of MIDI controller 10 (pan) and a modulator set to control Stereo Pan position. Using an LFO to change an Instrument's pan is an effect often heard with electronic pianos, giving the sound a back-and-forth motion.

Filter Tone

Use care when modulating the Filter Tone, especially when going back and forth between positive and negative values. The Comb Filter is disabled when the Tone control value is negative, and bad-sounding artifacts can occur when the Comb Filter suddenly cuts in or out.

Filter Frequency

Modulating the filter peak frequency spacing of an Instrument allows you to create electronic swishing and sweeping sounds, without altering the note's fundamental pitch - sounds you'll recognize from electronic dance music. This effect is most apparent on Instruments with higher filter resonance settings.

Filter Resonance

Modulating filter resonance tends to add a pulsating character to each note. If you turn on Track Pitch (on the Filter page), then you can create a pulsing harmonic at a pitch above or below the key played by using a semi-tone offset.
Note that filter resonance is perhaps the most subtle modulation destination. When the filter is not set to Track Pitch, the effects of resonance in general vary depending on the pitch of the note played. When Track Pitch is enabled, the behavior of different pitches is more consistent.

Modulator Types

The Beatnik synthesizer supports four different modulator types, all of which are based on two signal sources - a Low Frequency Oscillator (LFO) and an Envelope generator. Choosing a modulator type is easier once you understand how they differ:
Modulator Type.
Description
Low Frequency Oscillator (LFO)
An LFO applies a continuously repeating wiggle to an Instrument parameter, such as pitch or volume. This wiggle continues as long as the note is held.
You can think of an LFO as an invisible monkey turning an Instrument control knob up and down at a certain rate. If the knob the monkey is turning happens to be "volume," you'll hear the level of that instrument rise and fall periodically, like the tremolo effect on an old guitar amp.
LFO's have three important settings: how fast the knob is wiggled, how far the knob gets wiggled relative to its starting position and the "shape" of the wiggling gesture. In the Modulation window, these three parameters are represented by Period, Depth and Shape.
Envelope

An Envelope applies a one-time gesture to each note. Once the envelope is complete, the note continues normally until released. Use envelopes for any gesture that begins anew each time a note is struck - for example: a filter sweep, a pitch bend, etc.
The difference between an Envelope and an LFO is that LFOs produce a continuously repeating wiggle; by contrast, Envelopes happen just once per note, regardless of how long that note is held.
If you've worked with MIDI or digital audio software that supports mix automation, you might want to think of an Envelope as an automation curve. When a note is triggered, the envelope will begin playing, modulating the Instrument parameter to which it is attached. The difference between envelopes and automated mixing is that the envelope has the option to "freeze" during the sustain portion of the note, then continue after the note is released.
LFO with Depth Modulator (Envelope)
LFO with Depth Modulator uses the Envelope to vary the Depth parameter of the LFO. This creates a wiggling effect who's intensity changes over time. Notice how the shape combines elements of the previous two modulator types - the envelope modulates the LFO's depth, but not it's frequency or shape.
The actual result of this type of modulator is determined by multiplying the LFO's Depth setting (0-100%) and the current value of the Depth Modulator envelope (-100%-100%).
When using this type, you may want to set the LFO Depth to 100%, as this gives you maximum control and flexibility with the Depth Modulator envelope.
Negative Depths: In some cases, an envelope with points at levels less than zero (in the range of 0 to -100%) may have the same result as if the point was simply at zero. In cases where negative modulation values have an effect, be mindful of envelopes that have points both above and below the zero line - the modulation's destination will "invert" its behavior when the envelope crosses from negative to positive, which can produce interesting and complex sound behaviors. Predicting the results before you hear them will take practice!
Offset Modulator
Offset Modulator combines the LFO and Envelope in a different way. In this type, the LFO's Depth is still controlled by the envelope, but the Envelope shape is also added together with the LFO's shape. The result is an "offset," which you can seen by comparing the diagram with the LFO with Depth Modulator immediately above.
The Offset Modulator adds an Amount to use as ADSR % slider to the Modulator page.


Modulation Tips

Modulation is a classic synthesis technique. Here's how to get some familiar modulation-based effects:
  • Vibrato: Use an LFO mapped to Pitch. Usually the LFO depth will be set quite low. Note that if there is a Pitch Change LFO present in an Instrument, the Mod Wheel (MIDI controller 1) will affect its depth. Otherwise, Mod Wheel will activate a default Pitch Change LFO that cannot be edited by the user. Using an LFO with a Depth Modulator envelope that slowly ramps up or down can be very effective.
  • Stereo Panning Effect: Use an LFO mapped to Stereo Pan. This can be an adequate substitute for using a stereo sample; the triangle wave shape offers the smoothest result, square and sawtooth are more striking. Using an LFO with a Depth Modulator envelope that slowly ramps up or down can be very effective.
  • Tremolo: Use an LFO mapped to Volume, or to Filter Frequency with a low filter resonance setting. Using an LFO with a Depth Modulator envelope that slowly ramps up or down can be very effective.
  • Filter Sweep: Use an LFO mapped to Filter Frequency with a high filter resonance setting. The LFO rate should be very low (long period). Achieving your desired effect will probably require a lot of experimentation with adjusting the LFO and Filter parameters.
  • Arpeggiator Effects: Modulate Pitch from two or three LFOs with different but arithmetically related frequencies. This will create repeating arpeggiator-like effects. For example, examine Special Bank #99, Analog Sequence. Alternatively, offsetting the LFO frequencies by smaller arbitrary amounts can create interesting and complex effects.

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