Volume pedals and expression pedals may look exactly the same however they serve completely different functions.
These nifty pedals give you an expressive way of creating new and exciting sounds with your guitar by using your foot to rock back and forth and control different parameters. Let’s take a look at what you need to get the most out of a volume or expression pedal.
Volume pedals can do a number of different things to your signal including acting as a Master control over the volume of your guitar (obviously). A volume pedal is also a great way to create lush, sweeping soundscapes when used with an ambient reverb or delay pedal.
There are 2 types of volume pedals that you can choose from. Both choices have pros and cons to a certain extent, however, you’ll need to shop carefully to find the right one for your needs.
The 2 main types are active and passive. Make sure you know the differences between the 2 before going and buying one. Passive volume pedals tend to be cheaper however they don’t serve the same purpose as an active volume pedal.
Passive volume pedals are incredibly simple. They’re the equivalent of the volume control in your guitar in a foot pedal format on the floor.
They have a completely different feel to an active volume pedal with a different sweep and sweet spot. They tend to feel less sensitive and have a wider sweep (depending on the potentiometer inside of course)
A passive volume pedal doesn’t need power to be used and doesn’t have a buffer or any other circuitry inside.
Note: If you connect your guitar directly to a passive control you can – and probably will - experience a loss of top-end. This is because you’re running your signal into too much resistance, early on in your signal chain. The volume potentiometer on your guitar will have a resistance rating. And if you add more resistance with a volume control then you’ll notice signal loss. Nobody wants that.
Active Volume Pedals are probably the most commonly used and certainly the most popular of the two.
An active volume pedal has got a buffer inside which is why these pedals need to be powered by a power supply connected to a wall socket (or a power supply). If you don’t know what a buffer does, why not read our guide by clicking here!
The best thing about an active volume pedal is that because of the buffer, you don’t have to worry about signal loss. You’ll get a clean, streamlined signal that can be easily tamed.
The most important factor that’ll affect what a volume pedal does in your rig is where you place it in your signal chain.
The most commonly used signal chain will look something like this:
Guitar -> tuner -> wah/filters-> compressor -> fuzz -> overdrive/distortion -> pitch-shifting -> modulation -> delay -> reverb -> Amp
The volume pedal can be put into 3 common spots:
Beginning – A volume pedal at the beginning of your signal chain will act like the volume pot on your guitar. It’ll clean up your signal if you’re running into a distorted amp or even if you’re running it before any drive pedals. That signal will be cleaned up and you’ll end up with less grit and gain.
Middle – One of the most common places to put a volume pedal is in the middle of your signal chain; after your overdrive, distortion and boost and before modulations and reverbs.
This is the best way to ensure you keep the same amount of drive on your signal and simply turn that up and down and retain the trails from your reverb and delay. Most songs you play will require the trails to continue which is why this is the most obvious spot to have your volume control.
End – Having the volume pedal at the end of your chain – i.e. After delays and reverbs, will mean that the pedal acts as a master volume control. This will mean that any delay or reverb trails (the repeats or sound when you’ve stopped playing) will be stopped dead when you use the volume control. This is the best way to end a song abruptly or to have total control over your signal.
This way you can also bring down the overall volume without affecting how much gain you have.
Expression pedals allow guitar players to use their feet as an additional way to express themselves by altering the sound of an effect when the expression pedal is moved up and down.
Using an expression pedal with a delay will give you the ability to control Blend, Modulation Rate, Modulation Depth, Feedback, and Delay time on the fly. This means you can easily manipulate and twist the effectiveness of the delay on your signal and really warp your sound. It also makes it incredibly easy to create soundscapes within a song without having to bend over and adjust the Feedback or Delay Time manually. For more info on delay pedals see our Ultimate Guide to Delay Pedals.
You probably wouldn’t think of dirt pedals when thinking about expression pedals however there are some great drive pedals that’ll allow you to enhance or reduce the grit on your signal with an expression pedal. Moog and Stone Deaf are the industry leaders when it comes to dirt boxes with expression pedal outputs. For more info on overdrive pedals see our Ultimate Guide to Overdrive & Distortion Pedals.
Modulation effects are probably the most obvious when it comes to talking about expression pedals. If you consider the fact that a wah pedal is a type of expression pedal. If you want to know more about wah pedals, check out our guide by clicking here. For more info on modulation pedals see our guitar pedal guides.
You can easily control Volume, Intensity and Speed with most modulation pedals connected to an expression pedal. This is the easiest way to get those super expressive Hendrix-esque Uni-Vibe tones. Wild, screechy, and lush.
Multi-Effects units are incredibly powerful and connecting an expression pedal will only further enhance the functionality of a multi-fx by giving you the ability to change from controlling a delay to a reverb or a modulation depending on settings on your multi-fx pedal. For more info on multi-effects units see our Ultimate Guide to Multi-Effects.
An expression Pedal works by feeding a control voltage to a device – such as a synthesizer or a guitar. This voltage is then read by the device and then used to change one of the parameters. The parameter could be anything from delay time on a delay pedal to the depth of a Chorus.
The voltage range depends entirely on the type of pedal but normally sits between 0v and 5v DC. The expression pedal itself has nothing to do with that voltage range as it is just used to manipulate the voltage going into the device.
The way most expression pedals work is by taking a reference voltage from the device it’s connected to and halving that (depending on the position of the expression pedal) and feeding it back into the device which alters the sound.
The most common way for this to happen is through a TRS jack. A TRS (tip / ring / sleeve) is a cable where the reference voltage is on the ring. The control voltage is on the ‘tip’ and the ‘sleeve’ will ground the connection.
Expression pedals generally use a passive potentiometer like a common volume pedal. When the treadle is moved up and down, it controls the pot which in turns affects your sound in a pleasant and controllable way!
The expression Pedal won’t be directly ‘in’ your signal chain which means it can pretty much go anywhere on your pedalboard, as long as it’s connected to the pedal you want to control.
Expression pedals can be bulky which is why they’re often kept directly next to the volume pedal to save space. The general rule of thumb would be to simply put the pedal wherever makes sense on your board. Just make sure nothing will get in the way of the up and down action of your pedal.
Most expression pedals are fairly similar and the differences in price will normally be an indication of materials used rather than ‘better’ or ‘worse’ sound. Fortunately, Mission Engineering specialise in expression and volume pedals. Their pedals are definitely the industry standard and they’ve also got a choice of different pedals for different applications. Especially if you need an expression pedal for use with something like a Line 6 Helix or a Kemper.
Other industry leaders like Boss, Line 6 and Dunlop have also got expression pedals that’ll all do what you need them to do. We’d recommend buying for the amount of space you have on your board. If you’re gigging regularly you’re probably going to want something with a metal chassis. If you’re just a home player and want something to experiment with or use for recording, then a plastic expression pedal will definitely do the trick.
A voltage divider used for measuring electric potential. In guitar terms, a potentiometer will determine the amount of signal passing through and hence the overall volume. So, it’s the potentiometer in your guitar that will turn your guitars volume up from 0-10. Or, the tone knob will change the tone from 0-10.
