Amp Footswitch Guide: What It Does and How to Choose the Right One

An amp footswitch lets you change things on your amplifier with your foot: switch channels, turn on a volume boost, or switch the effects loop on and off. It does not process your sound; it only tells the amp's switching circuit what to do. The most important rule is that the footswitch has to match your amp model and version.

What an amp footswitch controls

What a footswitch can do depends entirely on the amp. Common functions are:

• Channel switching: moving between a clean and an overdrive channel, or between more channels on a three-channel amp.
• Volume or boost: jumping to a second, louder level for solos.
• Effects loop on/off: taking the pedals or rack units in the loop in or out of the signal.
• Reverb on/off: on amps with built-in reverb.

Each function needs its own button, which is why footswitches come in versions with one, two, three or four buttons. A button that does nothing on your amp is just clutter on the floor, and a footswitch with too few buttons leaves functions you can't reach while playing.

How a footswitch connects to the amp

Most amp footswitches are simple: a set of switches in a sturdy box with a cable to the back of the amp. Inside the amp, the switches trigger relays or other switching circuits. Because there is no signal going through the footswitch, it doesn't affect your tone.

That simplicity hides an important detail. Different amps use different connectors, wiring and switching logic. Two footswitches that look alike can be wired completely differently. A footswitch made for one amp may do nothing, do the wrong thing, or keep a function stuck on when you plug it into another. So don't assume a footswitch from another amp, or a generic one, will work. Use the one made for your model, or check with the builder first.

Latching and momentary switches

Amp footswitches are almost always latching: press once for on, press again for off. That is what you want for channels and loops. Momentary switches, which are only on while you hold them down, are used for things like tap tempo on pedals. If you build your own switching system or use a switcher on your pedalboard, check which type your amp expects.

Matching a Kool footswitch to your amp

Kool footswitches are matched to specific amp models and versions, and each comes with a detachable cable. According to the product page:

• 1 button: for the 11, Blue Sky Reverb and ACE Standard (2015 to 2018 version).
• 2 buttons: for the ACE 2019 version.
• 3 buttons: for the 1984, Black, ACE Deluxe (2015 to 2018 version), Marvell and Dark Matter.
• 4 buttons: for the Marvell Deluxe.

Notice that the Ace appears in three groups. The right footswitch depends on the year and version of your amp, so check yours before you order. If you're not sure, send Kool the model or serial number.

Each Kool footswitch is handmade in Kool's own custom shop and has a 3-year warranty covering defects in materials and workmanship.

What the footswitch does on Kool amps

Marvell

On the Marvell, the footswitch controls channel selection, the effects loop and both Loud & Louder settings. Loud & Louder lets you set one level for rhythm and a higher one for solos. The effects loop has relay true bypass and a level control on the back. Without the footswitch connected, the loop stays on. That is useful to know if you forget the footswitch at a gig: your loop effects still work.

Ace

On the current Ace, a two-button footswitch switches between Volume and Volume Boost, and turns the effects loop on or off. The Ace is a single-channel amp, so the footswitch gives you two levels rather than two channels.

Like every current Kool amp with a loop, these loops are ultra transparent, so your effects don't color the original tone. You can read more about how a loop works in series effects loop explained.

Practical tips for using a footswitch

• Place it where your foot lands naturally, usually at the edge of your pedalboard, so you don't have to look down.
• Route the cable safely. Tape it down on stage and keep it away from mains cables to avoid tripping and accidental unplugging.
• Bring a spare cable. A detachable cable makes this easy and is the part most likely to get damaged.
• Plan your switching. Decide which changes the amp handles and which your pedals handle. Using a boost pedal in front of the amp together with the amp's own channels gives you a lot of options with few buttons.

If you are still deciding how many channels you need, the guide to a two-channel tube amp head walks through the choice.

Next step

Find the version that fits your amp on the Kool footswitch page. Not sure which year or version you have? Contact Kool with your model or serial number.