This is a Guitar PreAmp & Distortion DIY excellent quality PCB,
and that mean double pedal.I mean just like PreAmp Guitar Pedal
(ByPASS OFF), or Distortion Guitar Pedal (ByPASS ON).
A switch (single or footswitch 2PDT) can be added via ByPASS
to turn the distortion on and off (just as with a guitar effects pedal).
If final you will put external footswitch, recommenduse mono jack
for ByPASS switch.
Note : The "ByPASS" switch only turns off the distortion, not the
tone control section. It is therefore not a real ByPASS ...
My preference is the OPA2134, which gives a somewhat "smoother"
soundthan, for example, a TL072, which sounds a lot coarser. Other
opamps which are alsoused by guitarists in Ibanez TS9 pedals are,
among others, the LM358, the LM833, the LT1124, the OP227 and
To make it easy to try several different opamps it is a good idea to
use an IC socket for this. You can then simply plug in the opamp of
your choice and it is also very easy to swap it for another type.
My prototype we used two standard 1N4148 diodes, which generate
a very pleasant sound. A 1N4007 results in a somewhat "hulking"
sound, while germanium diodes, such as the 1N34, provide a softer
sound. The 1N914 is also a good candidate. Combinations of diodes
are also possible, for example a 1N4148 connected in anti-parallel
with two germanium diodes connected in series. Each of these results
in a sound that is slightly different, which may appeal to one person
but perhaps not another. So we strongly recommend that you
- Bypass switch option for the distortion
- Adjustments for Drive, Tone and Level
- Power 9VDC (adapter or battery) about 20 mA.
® 2012 (c)