Best Envelope Filter Pedals 2018 – Buyer’s Guide

Looking to get that 1970's Jerry Garcia guitar mutron sound? Wanting a solid funk guitar tone?


...the envelope filter pedal (sometimes called the auto-wah).

Envelope filter pedals are among the most distinctive sounding guitar pedals out there, and the most fun you'll have with your clothes on :p

Did you know?

  • Envelope filter pedals are a little bit like the wah pedal we’re all familiar with in that they directly change the tone of your instrument by altering the frequency of the signal.
  • Unlike most guitar pedals, an envelope filter pedal doesn’t require any input once you’ve adjusted the settings and linked it up with the rest of your effects board.

Check out our buyers tips further down the page for more advice on what you should be looking for when you’re buying one. Now let's look at our five favourite pedals...

At a Glance: Our Choice Of The 5 Best Envelope Filter Pedals On The Market

Note: The links above take you to more information, current prices and customer reviews on Amazon. If you do purchase something we get a small commission, which has absolutely no effect on the eventual price that you pay.

Buyer's Tips: What to look for when buying envelope filter pedals

This is one of those rare pedals that’s more commonly found in a bassist’s arsenal than anyone else’s, but don’t think that’s their only use. Bassists and guitarists alike can make great use of these pedals. Today we’ll just be concentrating on those made for guitarists, (sorry, bassists!) but many of the pedals available also have an alternative for basses, with the only difference being the frequency range - so please bear this in mind as you continue.

There are two main styles of this pedal, volume-controlled and time-controlled.

Both modulate the signal of your instrument, emphasising different parts of the sound depending on how you see fit. For example, the low tones might be allowed to “pass through” whilst everything else is decreased. As the pedal modulates the signal automatically for you, you can go far beyond what would be possible with a manually controlled wah pedal.

The simplest way to imagine how they work is like the audio equivalent of applying a filter to a picture.

So now we know what they are, what sets the best envelope filter pedals apart from the rest?

  • Additional settings that cover things such as the options for more than one filter, resonance, and sweep direction.
  • You should be aware of whether the envelope filter you’ve just picked out is voiced for bass or guitar - there is a difference and it can make a great pedal seem mediocre.
  • Different envelope pedals have different timbres. Some are better suited for the disco/funk of the original incarnations, others player nicely with synth-driven electro. Make sure you try a few out to get the right pedal for your style.

5 Best Envelope Filter Pedals

Ok let's look at each product in more detail. To make things easier for you, we've added pros and cons for each one, as well as a video demonstration so you can them in action.

1. Electro Harmonix Q-Tron

Electro-Harmonix Q-Tron Plus XO Envelope Follower Pedal

This is one of the most popular, and is often held to be one of the best envelope filter pedals around thanks to its iconic tone, although this is influenced in part by how common it is rather than any special innovations.

  • Four filter modes, speed, volume and intensity settings give you plenty of options for fine-tweaking and adjusting the character of the filter
  • Rather cool looking, it holds to its funk and disco roots in aesthetics as well as its tone.
  • Has the choice of an up or down sweep
  • Although the four filter modes are pretty great, it’s surpassed by other models which offer much more
  • No expression-pedal options so you’ll need to set-and-forget this pedal.
  • Although not expensive by any measure, it doesn’t provide the best value for money

Let's take a look at this product...

2. Electro-Harmonix Riddle: Q-Balls

Electro-Harmonix Riddle: Q-Balls for Guitar Envelope Filter

Is it just me or do these pedals all seem to have silly names? Regardless, this is an upgrade from the Q-Tron, so take everything you liked about that pedal, and prepare for a little more. The best thing is that this pedal is only fractionally more expensive, but provides much better value.

  • All the circuitry is analog, which helps to keep the 70’s sound alive (who said disco is dead?) and doesn’t interfere with your signal if this is part of a chain.
  • Jack for an expression pedal giving you more intimate control of the filter’s sweep direction and depth
  • Controls for attack, decay, sensitivity and Q (which means how many frequencies are affected by the envelope pedal’s settings)
  • Has one less filter compared to the Q-Tron
  • The filter options which are available aren’t particularly creative, so if you were looking to experiment beyond the classic sounds of envelope filter pedals you’ll be disappointed by the lack of options
  • It’s a rather basic design, and the small size of the dials can make it difficult to see the settings if you need to change them under poor lighting (which as well know can be a real pain for a gigging musician)

Let's take a look at this product...

3. Source Audio SA127 (Budget Choice)

Source Audio SA127 Soundblox Guitar Envelope Filter

The SA127 delights in playing with the old adage that less is more. You get enough variety to play around with forever, but it’s all contained in an ultra-compact design. In keeping with the disco roots, it’s bright purple. It’s also excellent value for money, especially when compared to either of the Electro-Harmonix models.

  • An unholy array of choices, you get 21 filter options all controlled by a single dial
  • Three additional dials for controlling attack, decay, sweep, range and sensitivity
  • The whole pedal has a remarkably slim profile considering all of the options available, meaning it’ll fit snugly on any pedal board
  • Many of the controls are merged together. Although this works quite well most of the time thanks to the way they’ve been paired up, it can limit the degree of control you have.
  • No expression pedal options
  • Since the controls are combined into just four dials, you’ll have to spend a little time learning how they all work together in order to ensure the best results, unlike with other models where you can play with one setting at a time to learn its ins and outs

Let's take a look at this product...

4. Pigtronix EP2 (Editor's Choice)

Pigtronix EP2 Envelope Phaser Guitar Effects Pedal

Possibly the worst looking pedal so far, don’t let that put you off. It’s a little more expensive than the others, but also comes with some extremely great features that set it above more basic varieties of envelope filter pedals with ease.

  • Has not just one, but two inputs for expression pedals that allow you to control speed and sweep direction seperately, plus an input for a “trigger” that allows the envelope filter to be controlled by other external sources.
  • The Staccato switch enables the filter to adjust to every note even when playing at inhuman speeds to ensure perfect articulation even if you decide to bust out the shredding and sweep-picking. Could this be the envelope filter for metalheads? Just maybe!
  • Has some truly fantastic tone, which you can endlessly play with thanks to the huge range of controls
  • Although you get a lot in one package, this pedal is quite expensive and if all you need is the standard funk/disco sound, you would do better to look at some of the simpler pedals available
  • The complexity of the controls might take a while to get used to (have you ever tried to use two expression pedals at once? It can end spectacularly badly when you forget which is which)
  • It uses an 18v battery, which gives great headroom, but can put a bit of dent in your bank account as this thing runs through juice like you wouldn’t believe if you can’t use a mains power supply or a rechargeable battery.

Let's take a look at this product...

5. Maxon AF-9

Maxon 9-Series Auto Filter

This filter takes a straightforward approach to give you a no-fuss answer to your envelope filter pedal needs. It looks a bit retro, but considering the sound it produces, perhaps that’s in line with what it should be.

  • Built like a tank. There’s very little that’s vulnerable to damage, and it can safely be carried around from venue to venue with no problems at all for years. It can even take a hell of a beating, making it live up to the stomp part of “stompbox”
  • True bypass means it won’t ruin your tone when not in use
  • Nice warm tone that closely resembles the legendary Jerry Garcia sound that gets people interested in envelope filter pedals for the first time more often than not
  • It’s a basic pedal, lacking some of the extended functionality and fine tuning controls of others
  • It’s quite expensive for the simplicity of the pedal
  • No expression pedal input available

Let's take a look at this product...

So which should I buy?

So, the question still stands, which is the best envelope filter pedal?

It depends on why you’re looking to get one, if you just want that classic 70s bow-wow cheesy porno sound, then you’re in luck as all 5 mentioned today are more than capable of doing that. But chances are you’ll want to fine-tune it to either mimic the greats exactly or get your own signature sound.

For this reason, the Pigtronix EP2 and the Source Audio SA127 should be the top of your list. The EP2 offers a lot of fine tuning, and the two expression pedal jacks really put all of the control you could ever want in your hands (and feet), but if you find all of the options a bit overwhelming and would rather just dive in, then the SA127 might be more your style thanks to its merged controls and massive range of filters for quick exploration.

Have you had one or more of these pedals? Let us know which is your favourite, and why, in the comments below. If you’ve got another that we didn’t mention, don’t hesitate to get involved. Sadly we don’t have room for every pedal out there, so take the chance to help out your fellow musicians!

Ged is Founder and Editor-in-chief at Zing Instruments. He’s a guitarist for London based gypsy jazz band ‘Django Mango’ and a lover of all things music. When he’s not ripping up and down the fretboard, he’s tinkering with his ’79 Campervan.

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