Tiptop Audio / Buchla 259t Programmable Complex

Programmable Complex Programmable Complex Waveform Generator Model 259t is a complex oscillator module with two high-precision analog oscillators.

It has a modulation function that allows access to FM/AM/Timbre modulation functions via the switch's internal wiring, and its modulation amount can be controlled via CV, and a Timbre/Harmonics function that allows modulation of wave shaping. The 259t is a Eurorack format reproduction of the complex oscillator module, the original West Coast-style oscillator.
As a major feature, it also supports the ART format, allowing automatic tuning using ART-compatible modules such as OCTOPUS and ART QUANTIZER. This allows for quick response to melodic applications.

Oscillator Section
259t has two oscillators: the MODULATION OSC (modulation oscillator) and the PRINCIPAL OSC (principal oscillator).

MODULATION OSC (Modulation Oscillator)
has a fixed triangular wave output plus a signal output switchable between triangular, square, and sawtooth waves; it can switch between LFO mode and audible oscillator mode, and its frequency control is 1V/OCT or ART signal. There is also a CV output for use in modulation applications.

PRINCIPAL OSC (Principal Oscillator)
has three audio outputs. Sine Wave, Square Wave, and a “Final” output that produces an infinite number of compound waveforms via the Timbre and Harmonics sections.
The Principal Oscillator operates in the audible range, but its frequency range can be adjusted up or down by adding an offset with CV. It is also possible to switch from 1V/OCT to ART.

Both oscillators can be used independently, or the modulation oscillator can be used as a modulation source.

Modulation Section
The Modulation Oscillator can be used to modulate the Principal Oscillator into the FM (frequency modulation), AM (amplitude modulation), and Timbre sections. The amount of each modulation can be adjusted with the “Mod Index” knob and its CV input. Multiple of these modulations can be enabled simultaneously.

Pitch mod. (frequency modulation)
When the switch is set to the left, the “frequency” of the principal oscillator is modulated by the modulation oscillator.

Ampl. mod. (Amplitude modulation)
When the switch is set to the left, the “amplitude” of the principal oscillator is modulated by the modulation oscillator.

Timbre mod. (waveform modulation)
switch set to the left, the Timbre parameter is modulated by the modulation oscillator. This is a unique design feature of the 259t module.

PHASE LOCK:
The PHASE LOCK audio input jack has an attenuator that phase-locks the frequency of this oscillator to the frequency of the input signal. If the input signal frequency is close to or lower than the oscillator frequency, the oscillator is “locked” to the input signal frequency. If the frequency of the input signal is higher, the oscillator is “locked” to the nearest subharmonic of the input signal. This cancels out any unpleasant buzzing that may occur between two oscillators tuned in unison, octave, or harmonics.

Timbre/Harmonics section
The Timbre/Harmonics section has three wave shapers that can be crossfaded with the original sine wave.
The three wave shapers are as follows

Wave Folder (Wave Folder)
Sawtooth Wave
M Shape (similar to a square wave)
The Order knob crossfades between the Wave Folder and the Sawtooth/M Shape.
If Order is set completely low, the output is only the wave folder, in which case the Timbre knob is the parameter for the amount of waveform folding (Fold).

Symmetry changes the folded shape to asymmetrical by adding DC (direct current) to the audio signal going into the folder; with Order fully high, the Symmetry knob causes the sawtooth/M shape to crossfade.

The Timbre knob crossfades the timbre between the sine wave and the wave after wave shape.

Pitch Control with ART
259t The oscillator pitch can be controlled manually with the 1V/OCT CV or automatically with higher pitch accuracy using the Auto-Tune function with ART Note that the CV FM input is disabled when ART is enabled. Note that when ART is enabled, the CV FM input is disabled. Audio FM and all other inputs are enabled.
To use ART, you will need an OCTOPUS or ART QUANTIZER module.

About the Buchla & Tiptop Audio “Eurorack 200 Series”
The Eurorack 200 series is the result of a collaboration between Buchla, the legendary synthesizer manufacturer on the West Coast of the United States, and Tiptop Audio. The 200 Series, a very rare modular synthesizer developed almost half a century ago, has been reproduced in the Eurorack format. Bringing the quintessential West Coast style synthesis of the Buchla module to the many modular players of today, the Eurorack 200 series will bring a West Coast flair to your modular system.

Width 34HP
Depth 25mm
Current consumption +12V : 260mA
-12V : 105mA