Aron Nelson has become a tireless experimenter with distortion devices. His latest trick is the Hornet. This is a variation of the classic Fuzz Face circuit with a twist - it may very well be almost all things to almost all people, at least the ones that like Fuzz Face style distortion.
The Hornet circuit is very much the same and works like other Fuzz Faces (for more on how those work, see The Technology of the Fuzz Face) but has been optimized to allow the builder to tune in a set of transistors very easily. Transistor gain variation shows up plainly in the Fuzz Face; Aron has subbed in trimpots for four of the circuit's six resistors so you can tune to your heart's desire, matching most transistors to the circuit.
In addition, the Hornet adds a high-gain twist. In the classic Fuzz Face, the second transistor has a subsidiary role. It acts as an emitter follower in the biasing and distortion set up by the first transistor, and also adds some gain of its own. The character of the distortion is affected more by the first transistor, and the overall gain by the second one. Aron subbed in a silicon device for the second transistor, getting high gain, enough for massive overdrive, while keeping the input distortion character of the germanium first device.
I have laid out a circuit board for the Hornet, suitable for printing to toner paper and doing an iron-on. The board is laid out to facilitate:
The parts placement guide shows you how to populate the board and wire it up to the off-board components including true bypass switching, while the real-size toner transfer image lets you make an iron-on board simply and easily. The board includes space for a variety of industry standard trimpots, so whatever kind you use should fit in the board. The board accepts TO-5, TO-1, and TO-92 package-style transistors, and provides two test points for you to monitor the collector voltage of the transistors while you're tuning it in.
The thing works very well with either version of the Millenium Bypass to give you true bypass plus a status indicator LED with just a DPDT switch.
If there's enough interest, I'll have some etched and drilled, ready to solder boards made up for this beast. If you're interested in that, send email to "techie" at our new domain, geofex.com.
So what are you waiting for? Get going, get the parts and build one of these! They sound great!