It’s a preamp. It’s a JFET booster. It’s the Short Stack from Whimsy Machines! 

 

Whimsy Machines is a fairly new pedal company, based out of Fredericksburg, Virginia. But despite only being around since 2020, Whimsy Machines have come out of the gate offering some incredibly unique pedals in their “Dopecrumb” series. 

 

They’ve done a great job at crafting modern, interesting pedal designs and fitting them into fun, retro-inspired enclosures. And the Short Stack is no exception to this rule.

 

What is the Short Stack by Whimsy Machines?

 

The Short Stack is an ultra high-gain preamp and booster pedal that covers a wide range of amplifier-like tones. On the front of the pedal, three of the four knobs provide different flavors of gain (volume, level, and gain) – all of which ensure you are able to dial in sounds ranging from a sparkly clean boost to full-blown, crushing amplification. 

 

In other words, the Short Stack is very versatile and amp-like in its sound and feel. In fact, I liked it so much that I added it to our list of the best “Amp in a Box” pedals.

 

The Features of the Short Stack

Up front, the Short Stack is fairly straightforward. You are given four different knobs, all of which control different parameters within the pedal. And while “Gain”, “Volume”, and “Level” all sound like they sort of do the same thing, they all have very different roles within the pedal.

 

Let’s take a look at the controls. 

Volume: The “Volume” knob controls the output volume of the pedal.

 

Level: The “Level” knob controls the input level of the preamp. In other words, this controls how hard your signal is pushed into the preamp within the pedal. And much like an actual amplifier, a harder (louder) signal going into it will drastically change the way it behaves. 

 

Gain: The “Gain” knob adjusts the amount of gain or distortion coming from the pedal.

 

Bias: The “Bias” knob adjusts the amplifier bias point within the pedal. Set at noon, the bias point is centered, but as you turn the knob left or right, you change the characteristics of the preamp. This is great for dialing in unique tones. With the bias knob at either end of the range (at 0% or 100%) it can sound kind of broken – not in a bad way, but I much prefer the bias knob set right around noon.

 

The Short Stack also has a couple of tricks on its plate. If you open up the back of the pedal, you’ll find three different dip switches. All of which can play a role in shaping your tone. 

 

Half Stack/Full Stack Switch: Changes the topology of the amplifier. The Full Stack mode adds an additional +40dB of gain and has slightly softer clipping than the Half Stack mode.

 

Bacon/Sausage Switch: This switch changes between linear and non-linear negative DC feedback. I’ve found that this switch doesn’t affect the sound all that much, but it does change the way the pedal feels when you’re playing it.

 

True/Buff Switch: Changes between true bypass and buffered bypass

 

To hear the Short Stack in action, check out the demo above!

 

Overall, the Short Stack from Whimsy Machines is a unique take on a preamp-style pedal, and the folks over at Whimsy Machines have done a fantastic job of cramming a ton of tones and features into this pedal. This pedal would make a great addition to just about any gain stage on any pedalboard. 

 

Plus it comes in this incredible box!

 

To check out the Short Stack, or the other pedal offerings from Whimsy Machines, you can find their website here.