Fairfield Circuitry Shallow Water User Manual

TECHNICALS
- true bypass
- input impedance 1MΩ
- output impedance 2kΩ
- power supply 9 to 9.6 VDC
- current draw 40 mA max.
PHYSICALS
- 1/4” mono input/output jacks
- 2.1mm DC connector
- 4.7” x 3.8” enclosure dimensions
NOTES ON POWERING
Shallow Water was designed to operate using
your typical centre negative, regulated 9-9.6
VDC power supply. The pedal is protected
against reversed polarity and overvoltage
conditions. Always check your power supply
for proper voltage and polarity before con-
necting. There is no battery connection inside
the pedal.
ABSTRACT
Shallow Water’s essence could be
characterized as uncertain, subtle
and nostalgic.
Practically, this describes an
effect built around your typical
analogue chorus/vibrato circuit
wherein the signal is delayed by
a few dozen milliseconds using
a bucket brigade device. Another
signal then modulates this delay
time to create changes in pitch,
called vibrato. Chorus is achieved
by mixing the original signal with
the delayed signal, creating the
moving comb lters that tickle
our ears and feather our bangs.
Still, major differences can be
noticed when studying the k-eld
modulator’s architecture. The most
striking are how the delay time
is modulated in a random fashion
and how the recovery lter moves
in relation to the input signal.
Both these differences place
Shallow Water in a category of its
own, appropriately called k-eld
modulators.
As the present gets lost, the
future becomes the past.
PSEUDO RANDOM GENERATOR
The random quality of the modulation begins in a simple pro-
gram residing on a microcontroller. Its output resembles steps
of random voltages, seperated by random time intervals. The
RATE control effectively sets the overall range of these time
intervals.
INTEGRATOR AND DEPTH
These random stepped voltages are processed through a lter/
integrator, giving control over the slope at which the steps
will reach their new values. As DAMP is increased, the random
steps become slow and sluggish, instead of sharp and abrubt.
DEPTH denes the amount of modulation that will be used to
modulate the time delay of our input signal. There is a strong
interaction between all three controls affecting modulation; that
is, RATE, DAMP and DEPTH.
ENVELOPE FOLLOWER AND RECOVERY FILTER
Once the input signal has passed through the delay line, a
recovery lter and some kind of gate is necessary to remove
unwanted noise generated by the bucket brigade device. To
achieve this, the input’s envelope is followed and used to mod-
ulate the frequency of a low pass lter. The amount of envelope
is set by the LPG control, yielding bouncy, lo- responses to
quick and snappy gate-like behaviours.
EXTENDED WARRANTY
Faireld Circuitry will repair or replace any
malfunctioning product for a period of 2
years after purchase date. Problems resulting
from modications or misuse may cancel this
warranty. The owner will cover all shipping
expenses. This warranty applies only to origi-
nal owner of the product. Proof of purchase
might be required.
In short, the best thing to do is to contact us
as soon as possible with a description of the
symptoms, even if the warranty is expired.
SHALLOW WATER
K-Field Modulator
ENVELOPE
FOLLOWER
DELAY
LINE
ANTI-ALIASING
FILTER
DAMP
NOISE FILTER
+
INTEGRATOR
RATE
PSEUDO
RANDOM
GENERATOR
VOLTAGE
CONTROLLED
CLOCK
DRIVER
VOLUME
MIX
OUT
IN
VOLTAGE
CONTROLLED
LOW PASS
FILTER
LPF
DEPTH

Fairfield Circuitry Shallow Water Specifications

General

Type	Modulator
Technology	Analog
Power Supply	9V DC
Input Impedance	1 MΩ
Output Impedance	1 kΩ
Bypass	True Bypass
Controls	Depth, Rate, Mix
Jacks	Input, Output
Circuitry	Analog
Power Requirements	9V DC, center negative

Summary

Shallow Water K-Field Modulator Overview

Abstract

Describes the effect as uncertain, subtle, and nostalgic, built around a chorus/vibrato circuit with random modulation.

Pseudo Random Generator

Details the random voltage generation from a microcontroller, with RATE controlling the time interval range.

Integrator and Depth

Explains how random voltages are filtered/integrated, with DAMP controlling slope and DEPTH controlling modulation amount.

Envelope Follower and Recovery Filter

Covers the filter and gate needed to remove noise, using the input's envelope to modulate a low-pass filter's frequency.

Physical and Technical Specifications

Lists physical attributes like jacks and enclosure size, and technical specs like impedance, power supply, and current draw.

Powering and Warranty Information

Provides guidance on using the correct power supply and details the extended warranty terms and conditions.

Shallow Water Controls

Rate Control

Adjusts time intervals for random pitch fluctuations, with a wide range from rare to nervous.

Damp Control

Affects the modulation signal's slope, softening changes as DAMP increases.

Depth Control

Adjusts the intensity of modulation, with noticeable interaction with other controls.

LPG Control

Adjusts envelope level to the low pass filter and gate circuit for sound character.

Mix Control

Balances dry and wet signals, allowing for vibrato or chorus sounds.

Volume Control

Controls the overall output volume of the effect.

Advanced Control and Configuration

Boost and Pad Settings

Internal jumpers adjust input signal level and impedance for different sources.

LPG Adjust Trimpot

Fine-tunes the recovery filter's lowest frequency for sensitivity adjustments.