The Formula 5F6 reproduces the sound of the tweed Bassman® which, even though was marketed as a bass amp, is perfect for guitar. Depending on its volume you can get a sparkling, harmonically rich tone, or turn it up to get that famous on-edge-of-breakup character that is responsive to your picking attack, or crank it up more to get a thick, creamy, meaty crunch. It performs a quick compression on the initial attack that 'exhales' quickly into a wide clean with lots of glassy chime on top and a tight full low end. Lastly, the circuit was supercharged in its gain structure and tone circuit for much higher gain and a bright attack, this feature being accessible through an internal switch.
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