Harbinger Two
FX TYPE: Univibe
Just how lazy and inefficient am I? I’ll let you pass judgment. I first started working on what would become the “Harbinger
Two” around 2013. I knew I wanted to do a Univibe in a wah configuration, and I knew more or less how it should be done
(mostly less). Enter an endless parade of prototypes over the next 5 years. Mind you, I was not working on this constantly
- every year I would pick it back up and try to get it right. And, with each iteration I ran into some kind of problem. It went
like this: find problem, how to solve? Lemme just work on something else. The problems ranged from not understanding
how to control the LFO speed properly, bad voltages, bad response to speed control, etc, etc. But, I never gave up on it
and eventually I solved all the problems. And, I’m glad I did because this is a really good DIY project.
The Harbinger Two is very much a port of the Harbinger One into an expression control. If you’ve built the HB1, you can
certainly build the HB2. If you’ve never built a Univibe, you can certainly build and HB2, as well. But, and I want this to be
very clear: this is a time-consuming project. Expect to spend a few evenings putting it together. It’s not something you can
build in a single day and it requires patience and commitment. IOW, go slow and get it right the first time!
Details about the design: The Harbinger Two (like the One) does depart a little from the traditional Univibe design. It
includes an JFET buffer for a louder and brighter input option (the second input option is the stock Univibe). It also runs
all the audio at 18v instead of a regulated 15v. This gives the audio portion a little added headroom at the expense of a
small voltage drop (see the Voltage chart below for an explanation). The LFO section runs from regulated voltage like the
Univibe.
And, like the One, the HB2 only requires a 9v DC supply to operate. Lastly, the HB2 adds a new tweak: the Drag switch,
which creates a ramp down effect with mod rate.
Controls
SPD:
The rate of the modulation from fast (toe down) to slow (heel up).
INT:
The intensity of modulation.
VOL:
Output volume.
C/V:
This switch selects between a chorus effect (modulation mixed with dry signal) or vibrato effect (pitch modulation
only).
MOD/VIN:
This slide switch selects between the traditional input and a JFET buffer input. The JFET buffer has more out
-
put volume and is brighter.
DRAG:
This switch creates a slight delay and ramp-down effect of the modulation rate when going from Toe to Heel posi
-
tions.
GAIN:
This trimmer sets the brightness of the LFO-driven bi-pin lamp.
OFFSET:
This trimmer lets you adjust the ramping of the lamp’s brightness.
Terms of Use:
You are free to use purchased
Harbinger Two
circuit boards for both DIY and small commercial operations. You may
not offer
Harbinger Two
PCBs for resale or as part of a “kit” in a commercial fashion. Peer to peer re-sale is fine, though.