op-amp buffer and cab sim a full 18-volt
headroom when a standard nine-volt power
supply is used. The inverter stops the buffers
or the cab sim from being clipped, even
when the Getaway Driver has its output
volume cranked.
Also, because of the biasing of the single
ended part of the circuit, the overdrive took
on an EL84 type quality when used on a
nine-volt supply and an EL34 type quality
when used on a 12-volt supply.
I wanted the pedal to have a ton of output
level so that it could push the input of an
amp really nicely. I also wanted the pedal
the issue of having three single-ended JFET
to bridge the line between overdrive and
stages being out of phase, so I ended up
distortion. Overdrive pedals historically
using half of a dual op-amp for the input
sound lousy when used into a clean amp but
buffer, using the other half as an inverting
can sound good if the amp already has some
output buffer. This meant that the bypass
hair on it. Distortion pedals on the other
didn’t lose any signal whatsoever and the
hand cancel out some of the amp distortion
inverting output buffer put the gain structure
and only really work well into a clean amp.
of the pedal back in phase.
The Getaway Driver gives you the best of
I also wanted to add an analog cabinet
both worlds in the way that it works well
simulator to the pedal so that this came
into either a clean amp or an amp with some
out on a separate output jack which could
drive dialed in.
also be used to drive headphones. I used a
It also never gets lost in the mix like many
second dual op-amp for this.
pedals with limited output headroom often
Also, due to the asymmetric clipping nature
do. This is really noticeable when playing
of the gain structure, I realized I could
with a drummer and bass player. Some
probably do with more headroom on the op- pedals actually get quieter when engaged.
amp stages.
The last small addition I wanted to add to
I added a charge pump to invert the voltage the design was an internal DIP switch to
which generates up to -12 volts in addition
tame the top end when used on amplifier
to the maximum 12 volts. This gives the
clean channels that have a treble bleed
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