Mad Bean Pedals Rabbit Hole, Быстрый старт

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Overview
The Rabbit Hole is an open-ended project in which you can create numerous versions of the hugely popular Electro-
Harmonix® Big Muff™. The Big Muff™ is a staple of modern rock and has been used and popularized by innumerable
players in the last three decades. A components list has been included covering some of the many variations of this
effect. The Rabbit Hole is the same project as the Mudbunny but is designed to fit in the 1590A enclosure.
Notes

There are many transistors you can use in the Rabbit Hole. Alternatives to the 2n5088 include BC549C, BC550,
BC182L, 2n5089, and MPSA18, as well as many more. Using different transistors will create unique variations in
tone. Be careful to use the correct pin-outs, however. Some transistors, such as the BC549C will need to be
rotated 180° from the silk screen drawing on the PCB due to its reversed pin-out. Always check the appropriate
datasheet for your transistor BEFORE soldering.

You can also create unique tones by using different diodes in place of the 1n914 (or the equivalent 1n4148).
Different diodes such as germanium, LED, and mosfets (wired as diodes) offer the opportunity to customize the
Rabbit Hole to your personal taste. Typical alternatives include 1n34a, 1n270, BAT41, red or green diffused 3mm
or 5mm LEDs, and 2n7000 mosfets.

Using germanium diodes in the D3/D4 position will sometimes create a very light octave effect. If you use them for
both D1/D2 and D3/D4 you may get a slight “bloom” in the note decay (a VERY COOL effect). If using a mosfet
for clipping, simply solder the gate and drain pins together on each mosfet and use the two leads (source and
gate/drain) as the diode in a back to back configuration on the D1/D2 and/or D3/D4 positions. Keep in mind space
is very limited on this PCB so it may be difficult to fit some diode types.
Resistors
Use 1/8W, if possible. 1/4W will also work but you will need to stand them up and bend the leads over (see my build pic at
the end of this doc).
Caps
Film: 16v box-type film or similar. MLCC (multi-layer ceramic capacitors) will also work well.
Use low-profile 47uF electrolytic for C14:
http://www.mouser.com/ProductDetail/Lelon/SS470M1EBK-
0605P/?qs=%2fha2pyFaduiyAAvSlfMpbODw%252bnxU4%2fmF%2f7sbuj8QXWHZy94xWJbRVg%3d%3d
Pots
Alpha 9mm PCB Mount: http://smallbear-electronics.mybigcommerce.com/alpha-single-gang-9mm-pc-mount/
Jacks
I use these for 1590A builds
http://www.mouser.com/Search/ProductDetail.aspx?R=NRJ4HFvirtualkey56810000virtualkey550-10284
Which require these nuts: http://www.mouser.com/ProductDetail/Neutrik/NRJ-NUT-
B/?qs=S12Y1JoqO2B/J8w/0QDEXxm4CRfxKYczbewAXgkjeBc =
Both of these types should also work but may require adjusting the provided drilling template somewhat
http://smallbear-electronics.mybigcommerce.com/lumberg-1-4-compact-shrouded-mono-jack/
http://smallbear-electronics.mybigcommerce.com/1-4-in-mono-enclosed-111/
DC
Any of these will be fine
http://smallbear-electronics.mybigcommerce.com/dc-power-jack-all-plastic-unswitched/
http://smallbear-electronics.mybigcommerce.com/2-1-mm-plastic-round-external-nut/
http://smallbear-electronics.mybigcommerce.com/2-1-mm-all-plastic-round/
Knobs
Use ½” diamter knobs!