PRESENCE: This control governs frequencies in the 5khz range allowing you to tune the top end response to your particular pickups and amplifier. 

MASTER: This volume control has a heaping helping of output on tap, allowing you to dial in a huge, fat, woody clean tone or to push your amplifier into overdrive all on it’s own.

TONE: This parameter sounds and behaves just like it does on the actual Deluxe amplifiers - you will notice that as you wind up the VOLUME control that the TONE control’s influence becomes more subtle when the VOLUME is maxed out. At lower VOLUME settings, you can set it at noon for the flattest response; to the left of noon for those smoky jazz cleans; or crank it up for more barking, greasy upper midrange tones that slice through the mix. 

VOLUME: The VOLUME control is essentially your gain control. It works in concert with the HI/LO switch, enabling you to set your maximum desired level of dirt - from squeaky clean to DAMN THAT’S STANKY! Want to clean it up? Simply roll back your guitar’s volume knob! 

The HI / LO switch offers two discrete gain modes:

The HI / RED mode is the raging, hot-rodded 12AX7 mode with more gain and saturation. You’ll notice that your pick essentially turns into a ‘throttle’ of sorts - lay off the attack and it cleans up but there’s always that potential there for ‘acceleration’ when you lay into it!

The LO / GREEN mode is lower gain overall - as if your amp were now sporting 12AY7 preamp tubes. Cleaner and more immediate in the pick attack with more ‘bounce’ when you’re chord comping, but still has that fat, juicy harmonic response.

OK, got your guitar all tuned up?

Let’s start by setting the Formula No.55 in LO/GREEN mode (mode switch in the up position), PRESENCE - noon, TONE - noon, VOLUME - noon, and MASTER around 10:00. Go ahead and jam for a while through this setting. You should hear a nice mild cleanish overdrive (you may need to turn up the VOLUME control a little more if you’re using lower output pickups) with a fatness in the low mids that is inherent to the design regardless of TONE setting. Roll the volume control on your guitar back and you should hear the sound clean up really nicely. Now, go ahead and explore the PRESENCE and TONE controls to hear how they affect the EQing. Okay once you’ve got those two set to where you like them let’s crank up the VOLUME control all the way - play a palm-muted chord line and listen to the quality of the grit and the low end resonance that makes it seem like your cab is breathing. Nice, right? Now rip an open chord and let it ring - lots of grind up front that has fullness and clarity as it decays. Notice that ‘cab thump’ when you palm muted has disappeared and the low end got more focused and tightened up when you hit it hard? Now lay back with your picking hand with the guitar volume up full - IT’S CLEAN!

Okay on to the HI / RED mode!

BEFORE YOU PUSH THAT BUTTON let’s roll the VOLUME control back to about 9:00 -you’re basically picking up where LO / GREEN mode with the VOLUME cranked left off.

Notice the signal feels more ‘hyped’ - hotter, with lots of stored potential at your pick. Hit it hard and let it ring! Now lay back and brush the strings lightly - yep, still dynamic. Take the VOLUME up to noon and camp out here for awhile paying attention to the attack and dynamic characteristics - it’s fuller but still tight with lots of string definition when you lay into it. And of course it's still cleaning up when you want it. Now dime that VOLUME control!

Oh God. Yep. There it is.

Feel that? That elastic ‘sag’ when you smack it that blooms out bigger than the initial attack? So good. But wait - lay back again and brush those strings - WHOA. Now roll back your guitar volume and get at those tweed cleans. You’re probably gonna lose an hour or two here so it seems like a good time to bring this section to a close. Enjoy! 

You can power your Formula No.55 with a 9v battery or any good quality filtered andregulated 9-18vDC power supply with a center-negative tipped plug designed for use witheffects pedals. If you want more volume, headroom, and percussive attack, try running an18vDC power supply. A 9vDC power supply will have a slightly softer sound that saturates more easily - it's sort of like the difference between a 50 watt and 100 watt amp! Definitely try it at 18 volts though - there's quite a difference! 18 volts is great for playing with the band.You'll get great attack and clarity with power to cut through the mix. You can also try a battery that is drained down to as little as 3-4 volts to get an even softer sound that is great for late night jam sessions when you don't want to wake anyone up!To change the battery, just remove the four screws on the bottom plate. There are no other user controls under the hood. As usual, when running with a battery, unplugging the input jack will turn off the power.