12-15-2023, 12:27 PM (This post was last modified: 12-15-2023, 12:46 PM by makinrose.)
I recently was looking at some Garnet schematics and came across the built-in fuzz/distortion circuit they called the "Stinger". Has anyone player an amp with this feature? How does it sound? Being in the US I've never seen a Garnet in person.
The design is intriguingly simple---a parallel input gain stage that uses a 6AN8 with the signal going into the pentode section of the tube which is grid-leak biased and direct coupled into the triode section. The sound is then mixed into the parallel normal input stage's output. The one thing I'm not clear on is that since the fuzz/distortion it goes through two gain stages wouldn't be out of phase with the normal input stage's signal?
You must have heard Takin care of Business by BTO? Its been around for like a hundred years hahaha ok maybe like 40 years. I think Kevin said BTO used garnet amps
A quick look at Garnet's schematics suggests that the integrated Stinger fuzz effect was always 'clean' mixed with 'dirty' where the fuzz portion is out-of-phase with the clean signal.
The form used in the Rebel-series, shown in the PDF in post-1, has a 2-stage Stinger path in parallel with a single-stage clean path. The Stinger uses both the pentode and the triode of a 6AN8 as gain stages, cascaded for maximum gain but very limited headroom.
In later versions, such as in the BTO amps, a shared triode input stage produces the clean signal and drives the 6AN8 pentode. The pentode output is mixed with the triode's output.
In the Rebel / early version, the 6AN8 triode is direct-coupled to the pentode plate. Current through the triode is pretty low and that stage can distort very easily. The later version has the pentode seeing a n already amplified signal, so the pentode is driven to distortion while trying to drive the Stinger tone shaping from its plate, loading it quite a bit.
In either case, the mix of a square wave and a sine wave favors the square wave dominating the sound.
In Garnet's book, he shows a cascaded triode distortion circuit using clipping diodes at the output, similar to second-generation fuzz boxes that have an opamp gain block followed by clipping diodes across the output. he never states whether he used this circuit, just that it is an interesting idea.
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