Sunn amps are some of the most regarded in the guitarist community due to their huge thick sound, deep bass, and loudness. Every Stoner rocker dream!
However, these amplifiers can get pretty rare and expensive to purchase, often going for price tags above $3000. Even the 2008 Fender reissue can be quite hard to find.
The Sunn tone demand increased incredibly fast through the years due to the hype generated online, with many pedals claiming to nail its tone. Maybe the most popular being EQD Acapulco Gold, which delivers quite good tones but not even close to the Sunn Model T.
Meanwhile, in France, Coda effects developed the Black Hole, following the Sunn Model T’s original schematic, replacing the tubes for JFETS and making some other adjustments to squeeze more gain out of it we did with our Lemon Rockverb (link).
After being blown away by the Black Hole’s tone, I started asking myself, ‘ How can we make this even better?’
So, I started experimenting with the EQ section, which most often the weakest point of the JFET preamps in a box.
I wanted to try some of the EQs sections we have seen in other modern amps in a box, just like our Active EQ or Hybrid eq, both from Freeman BEOD or the Revvolution series, respectively (links in every name). Finally, choosing Benzin EQ as the winner. Keeping the traditional structure of an amp alike tone stack, while adding a Depth control to make your bass growl and a presence knob to make sure you’ll cut through the mixes, as a cherry on the top, we have a recovery gain stage after the tone stack, making sure this beast will tear your house down.
For further analysis on this circuit, take a look at this thread on Free Stomp Boxes Forum.