Buchla and Tiptop Audio — 281t Quad Function Generator

Manual PDF

Manual PDF - Buchla Tiptop 281t Quad Function Generator

Buchla Tiptop Audio 281t Quad Function Generator (Eurorack)

Cheat Sheet - Quick Reference

Core Overview

4 function generators (A, B, C, D), arranged in two linkable pairs (A+B, C+D).
Modes per generator: Transient, Sustained, Cyclic.
Can generate AD, ASR, or looping envelopes, or be paired for complex shapes or quadrature operation.

Inputs / Outputs

Function	Jack Type	Location	Voltage Range & Notes
IN	Input	Per generator	Gate or trigger; any voltage above ≈2V is treated as high.
CYCLE JACK	Input	Per generator	Trigger or gate to enable cycling via external signal.
CV ATTACK	Input	Per generator	Unipolar; 0–10V CV controls attack segment rate.
CV DECAY	Input	Per generator	Unipolar; 0–10V CV controls decay segment rate.
OUT	Output	Per generator	Envelope output; 0 to +10V range.
END OUT (Pulse)	Output	Per generator	Triggers at end of decay; 10V logic pulse.

Controls

Control	Type	Per-Gen?	Description
Attack	Knob	Yes	Sets rise time (0.001–10s).
Decay	Knob	Yes	Sets fall time (0.001–10s).
Mode	Toggle Switch	Yes	Sets mode: Transient (trig = AR), Sustained (gate = ASR), Cyclic (looping AD).
Trigger	Push Button	Yes	Manually fires the function generator.
Cycle Input	Jack	Yes	Accepts external gate/trigger to enable cycling.

Global/Paired Controls

Control	Type	Location	Description
Quadrature Switch	Toggle	Between each pair (A+B, C+D)	Pair generators; envelope of B (or D) is 90° out of phase to A (or C).

Operation Summary

Transient: Envelope rises on any valid pulse (trigger), falls immediately after reaching 10V.
Sustained: Envelope rises and holds at 10V while input is high (gate); falls when input goes low.
Cyclic: Envelope self-cycles (LFO or looping envelope) as long as cycle is enabled (via switch or jack).
Quad (Quadrature) Mode: Link pairs (A+B or C+D); B (or D) starts its cycle at peak of A (or C).

Voltage Ranges

Envelope OUT: 0V (min) to +10V (max)
CV Inputs (Attack/Decay): 0–10V
Pulse Outputs: 10V logic pulse

Physical Specs

Width: 28HP
Depth: 32mm
Power: +12V 160mA / -12V 55mA

Generated With Eurorack Processor