01 Complex Oscillator 22 HP

Everything here is an input waiting for a cable.

Patchfield is a quarterly for people who build instruments instead of buying them. Six modules, one signal path, no fixed reading order — start wherever the cable lands.

This issue: taming chaotic feedback loops, a teardown of the Buchla 259 core, and a field recording diary from a shed in Norrland where the power supply hummed at 51 Hz for eleven days.

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Coarse62 Fold34 Index81

Outputs

02

Ladder Filter — Three Long Reads

16 HP

Everything that survived the edit passes through here. Resonance set just below self-oscillation.

Teardown

The 259 Problem

Why the timbre section still can't be cloned in DSP, and what the 1973 tolerance stack actually did to the waveshaper.

Interview

Ilse Marchetti

Forty minutes on building a 12-voice drone rack out of salvaged telephone exchange relays.

Method

Feedback, Politely

A patch recipe for chaos that stays inside a mixing desk's headroom. Includes a safety limiter you can build for €9.

Patch note: pull the Fold cable from module 01 and the middle read becomes unreadable. That is intentional.

In / Out

03

Sequencer — Issue Contents

20 HP

Eight steps, eight departments. The running light is the table of contents.

STEP 01Cold StartEditor's letter — on the pleasure of an unpatched case4 min
STEP 03Norrland DiaryEleven days of 51 Hz hum, transcribed18 min
STEP 05Bench NotesSix new modules measured on the scope, honestly11 min
STEP 07Patch of the QuarterA generative rain machine in nine cables7 min

Clock / CV

04

Envelope — Bench Measurements

14 HP

Attack, decay, and the numbers nobody prints on the panel.

Measured on a 500 MHz scope, 24 °C, +12V rail
Module	Fastest attack	CV tracking	Noise floor	Verdict
Fenlow ADSR-2	0.42 ms	±3 cents / 6 oct	−94 dBu	Buy
Voss Contour	1.10 ms	±11 cents / 4 oct	−88 dBu	Fine
Kastl Slope	0.19 ms	±2 cents / 8 oct	−97 dBu	Buy twice
Hemlock Rise	3.60 ms	±26 cents / 3 oct	−79 dBu	Pass

Every unit was run for two hours before measurement. We publish the failures too — see the Hemlock, whose CV input drifts a full semitone once the case warms past 31 °C.

Trigger

05

Mixer — Join the Bus

8 HP

Four issues a year, printed on uncoated stock heavy enough to lie flat next to a soldering iron.

Ch 174 Ch 245 Master90

Sum

06

Output Stage — Masthead

4 HP

Edited in Rotterdam by Ada Kerrigan and Tomás Weill. Bench measurements by the Fenlow Lab. Printed by Drukkerij Bloem.

Patchfield takes no advertising from manufacturers whose modules it measures. Corrections are printed at the same size as the original error. If a cable in this issue goes somewhere it shouldn't, tell us and we'll re-patch it.

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