Mad Bean Pedals Aquaboy Deluxe, Quick Start Manual

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The Aquaboy Deluxe (ABDX) is a “feature expansion” version of the original madbeanpedals Aquaboy project. The ABDX is based on
the classic DM-2 analog delay with the addition of dual delay BBDs (for twice the delay of a DM-2), delay modulation and the ability to
use several different types of bucket brigade devices.
Improvements to the original Aquaboy design have been made in the area of power supply filtering and layout. Even though the PCB is
densely packed, it should be a relatively easy build for the experienced stompbox maker. The PCB will fit comfortably in a 1590BB
enclosure.
This is complex project that should not be under-taken by novice builders. It requires considerable effort in biasing and at least some
tinkering to tailor it to the builder’s needs. It is also a costly project to realize. Aside from the cost of the PCB itself, the BBD chips can
run anywhere from $7 to $80 for a pair (depending on what type of BBD technology you use). However, this is also the type of project
where money spent will go a long way toward making a unique and professional delay AND still be cheaper than most commercially
available analog delays out there. Indeed, there are very few true analog delays with 500ms of delay and modulation that are under
$200.
Controls
DELAY – The total amount of signal delay from slapback to approximately 500ms.
FDBK – The number and intensity of delay repeats from one to infinity/self oscillation.
MIX – The level of delay signal relative to the dry path of the guitar signal.
RATE – The speed of the delay modulation from slowest to very fast.
DEPTH – The intensity of modulation from moderate to extreme.
WAVE – This On/Off/On SPDT allows you to choose between triangle wave, none and square wave modulation.
Trimmers
T1 – Sets the maximum amount of feedback possible in order to control the total range of the FDBK control.
BIAS1, BIAS2 – Used to set the biasing point on the input of each BBD.
CANCEL – Sets the mix of the two outputs on BBD2.
CLOCK – Sets the lower limit of the clock frequency used to drive the BBD chips.
Changes to the 2015 edition
1. Layout tweaks. Relocated I/O pads to the bottom center of the PCB.
2. Added an optional “Tails” bypass which allows delay repeats to spillover when the delay is bypassed.
3. Relocated R55 and R27 before the two 82k biasing resistors rather than after.
4. Relocated BBD jumper pads where they can more easily be changed after-the-fact.
5. Updated PCB to 2015 Eagle library.