EARTHQUAKER DEVICES: Spires Green Channel

EQD Spires Green 015 vero v1 bb5983122697

The Earthquaker Devices Spires green channel is a variation of one of my favourite fuzz circuits – the Rosac Nufuzz.   It’s a progression of a fuzzrite from the original designer, but it has a tone control on the output sweeping between a small and large cap to provide a thin to thick fuzz sound.  There’s … Read more

TRANSISTOR, BRIMAR: AC113 Germanium Transistors

Brimar Mazda Thorn AC113 datasheet b356e4aa4b1f

Brimar transistors were made by Thorn and were also commonly branded as Mazda.  A full write-up can be found here The AC113 is an audio frequency amplifier or driver type germanium transistor. AC113  GERMANIUM TRANSISTOR DATASHEET TRANSISTOR EQUIVALENTS Being a fairly generic audio amplifier, they’re listed as being similar to a number of common amplifier … Read more

COLORSOUND x D*A*M: Fuzz Sound

COLORSOUND DAM Fuzz Sound 2 knob 015 vero layout v1 6576df17b251

Following on from the previous post, this is the D*A*M version of the Colorsound Fuzz Sound.  Thread on the D*A*M forum can be found here.   Basically take a D*A*M Fuzz Sound, and change the Fuzz pot to an internal trimmer.  Unlike the regular Park 2 knob with a large 25u coupling cap between the darlington … Read more

PARK: Fuzz Sound, Two Knob Version, tag board layout

PARK 2 knob fuzz sound tag board v1 70eeb490f49f

Request for Phil – one tag board layout for the Park 2 knob fuzz sound.   I generally prefer to keep the links below the board, as it looks neater.  I don’t mind linking two adjacent lugs on top, as you hardly notice it. One suggestion for this.   The D*A*M Colosround Fuzz Sound has a few … Read more

HOFNER: Germanium Pre-amp

Screenshot 2023 07 25 at 6.27.53 pm b127fb1c0943

I only came across the Hofner Preamp quite recently, despite seeing some other builders making point-to-point style germanium preamps based on this circuit – the prime example being the R2R Electric preamp. There’s a good write up here, but in summary: Back in the day before guitar amps were affordable, and TV was a thing, … Read more