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3Leaf Audio Proton Envelope Filter (v3) Bass and Guitar Pedal

3Leaf Audio Proton Envelope Filter (v3) Bass and Guitar Pedal

Condition: New


Out of stock


Player's Perspective

If you're a guitar or bass player who messes around with effects pedals, chances are you're already well aware of who 3Leaf Audio. Since the first version of their Proton envelope filter was released, these guys have really been pioneering the evolution of boutique pedals. Perhaps more known in the bass community than in the guitar community, 3Leaf are one of the few companies that truly make pedals that sound just as good on bass as they do on guitar. The Proton quickly became the standard for bass envelope filters and anyone trying to get that old school bubbly funk tone will know that your search can end right here. This pedal definitely leans towards the vintage side of things, tonally, and if you're a bass player, you can't help but make you jump back and go "aaaaahhhh... The name's Bootsy, baby!" And on guitar, anything from Jerry Garcia type tones to funky wah wah chugging are available with just the twist of a few knobs.

The knobs interact subtly with one another and there's really no way to get a bad sound out of this pedal. Under the hood, it is all hand-wired and hand-built by one of the ex-designers at Darkglass. Now hellbent on conquering the pedal market with his 3Leaf Audio and Pike Amplification companies, Spencer is truly cranking out some unbelievable pedals up in Seattle. Originally designed for bass guitar, with an emphasis of preserving the low-end frequencies, this pedal also sounds amazing on guitar (especially if you play 7 or 8-string guitars) and should not be thought of as a bass-only pedal. A faithful adaptation of the classic Mutron III, this pedal will either rekindle your love for envelope filters or only further exacerbate it. Either way, it simply sounds awesome and packs an awful lot of tone into a small enclosure!

Manufacturer's Description

The Proton is a modern homage to the classic Mutron III envelope filter. It has a wide frequency response that sounds great with every instrument. Version 3 has increased input sensitivity to work better with low-ouput instruments, and it adds a tone knob for variable control over the filter cutoff frequency.

Relay-based silent true bypass will automatically switch to bypass mode if power is lost.

Phase-correct output for predictable use in blend pedal signal chains.

Gain - Response of the filter to your playing dynamics. This should be adjusted based on the output of your instrument. Start with the sensitivity at minimum and turn up until the filter reacts to your liking

Decay - The time it takes for the filter to sweep. Higher settings produce long, nautral envelope sounds, while lower settings produce quicker, more “bubbly” envelope sounds.

Sweep - Direction of the filter’s sweep. In the up position, the filter sweeps normally. In the down position, the sweep is reversed. You may need to change the settings of the gain and decay knobs; settings that work in the up position won’t always work well in the down position.

Peak - The “wetness” of the filter sound. Higher settings produce a more aggressive sweep with a sharper resonant peak.

Tone - The maximum cutoff frequency of the filter. It works like the tone knob of a guitar or bass. Higher settings will accentuate the treble frequencies; lower settings increase the filter’s warmth.

Overall Condition

This 3Leaf Audio Proton (v3) is in brand new pristine mint condition with no nicks, scratches, or blemishes.


  • 3Leaf Audio Proton (v3)
  • Envelope Filter
  • Gain, Peak, Decay, and Tone Knobs
  • Sweep Switch
  • 9V DC Compatible (not included)
  • Relay-Based Silent True Bypass

Our in house guitar tech has inspected, tested, and cleaned all of our instruments on site prior to shipping. All of our instruments are guaranteed to be fully functional upon arrival.

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Our team of musicians fuses the spirit of the local guitar shop with the convenience of the web by creating a reliable and worry-free buying experience.

At Music Store Live, our goal is to revolutionize the way gear is bought online. It’s not just about videos and know how; it’s about the person on the other end of the line. Whether you are in Tokyo or Toledo, we invite you to experience the reality of a living online music store and help us shape the best buying experience possible. As you'll see in the video below, we're musicians just like you. We strive to offer the best gear, the best online experience, and the best personalized service in the industry. We invite you to get to know our team, and we would love the opportunity to get to know you too!

Free Shipping - Free Return Shipping - 30 Day Returns

At we are proud to offer free return shipping and a 30-day return policy in the 48 contiguous states on all new* items over $30. It's all part of our mission to bring the guitar shop to your living room. This policy allows you to get your gear hassle-free and try it with your own rig to be sure that it truly fits with your playing style and sound. If it doesn't work the way you had hoped we'll send you a prepaid return label and work up an exchange or issue you a refund once we get the item back in the same condition it was purchased. It's that simple.

Please allow 2-4 business days from the receiving date for returns to be processed.
  • Your order must ship to the billing address associated with your credit card, PayPal, or other method of payment (unless an alternate shipping address has been approved by an MSL Gear Specialist).
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  • All returns are subject to a Tech Check upon arrival. Any instrument that is returned with damage, wear and tear (including pick marks), missing or replaced parts, missing protective or packing materials are not eligible for a full refund.
  • *Used / Open Box/ Vintage / Clearance items carry our same return policy, except with a 3­ day return window.
  • Orders shipped within California will be subject to 7.25% state sales tax.

In most cases we ship same day if your order is placed by 12 p.m. EST Monday thru Friday!

Return Policy Details
Is your instrument just not doing it for you? We understand and we absolutely want you to be thrilled with any gear that you buy from If you're not happy with your order, you can return it to us at no charge within 30 days of delivery.

  • Customers outside the continental USA must pay their own return shipping and are responsible for all applicable taxes and fees.
  • The return policy does not apply to custom orders or modifications (pickup installs, etc)
  • Contact MSL at or (866) 256-5725 to begin the return process. You can request a refund, store credit, or exchange.
  • We'll provide you a return label via email.
  • Ship the item back to us in its original packaging using the provided return label.
  • Customer is responsible for returning the item to Music Store Live in its original condition.
  • A refund or exchange will be issued within 3 business days from our receipt of the returned item.
  • All returns will go through a technical inspection and are subject to a restocking fee if the item is not returned in its original condition. Restocking fee to be determined by MSL.

Layaways & Financing


  • Deposit a non-refundable minimum of 10% down of the purchase price on anything in stock
  • Contact MSL at or (866) 256-5725 to place your initial deposit.
  • Pay it off at your convenience within 30 days.
  • $100 layaway fee for each additional month over the initial 30 days (on most items).


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