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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.

Our Mission

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 - No Hassle Returns - 30 Day Trial Period

At Music Store Live, we are proud to offer free shipping on just about everything we sell. We’ve also got one of the best return policies in the business giving you a full 30 day trial period that starts when you receive your order for all new* items. 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 provide you with return authorization information to send it back for an exchange, a refund, or in-store credit. But no matter what, we’ve got your back and we are here to help make sure you end up with the right gear for you. You’ll never be stuck with something you aren’t happy with.

Return Policy Details

What if there’s something defective with the item I purchased or it arrived with shipping damage?

We’ve got some of the best guitar techs around to test out every instrument before it leaves our shop and give everything a full setup. We’re confident your order will arrive ready to rock right out of the box. Our awesome warehouse staff put time and care into packaging your order up to make sure it all arrives to you safely. But let’s be honest, once in a blue moon stuff happens that’s out of anyone’s control. If you received an item which you believe is faulty, shows signs of shipping damage, or in any way doesn’t meet your expectations based on the description in the listing, please do not hesitate to contact one of our Gear Experts. No matter what happens, we want to make it right! (note: If you believe there to be shipping damage, please do not discard the packaging that your order came in and please make sure to contact us within 24 hours of receiving your delivery)

What if I’m not liking it or it’s just not working out for me?

Is something you purchased from us just not doing it for you? We understand and we absolutely want you to be thrilled with any gear that you buy from Music Store Live. If you're not happy with your order, you can return it to us within 30 days of delivery*. You are welcome to return it for a refund, an exchange, or in-store credit.

  • Please allow 2-4 business days from the receiving date for returns to be processed.
  • If your purchase qualified for free shipping, we may withhold our outbound shipping costs from any refunds processed as part of the return.
  • Contact MSL at or call (866) 256-5725 to begin the return process. Anything sent back to us must have an RMA number and we may refuse returns that did not receive prior authorization.
  • Return the item(s) in its original packaging and in a way that will help ensure its safe arrival back to us.
  • Just as we’re responsible for getting your order to you safely, you are responsible for returning the item(s) to Music Store Live in its original condition. Please take care with packaging it back up and preparing it for the return shipping journey. We recommend you add insurance to higher value items when sending them back.
  • 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 but is not to exceed 15% under typical circumstances.
  • * B-Stock, C-Stock, E-Stock, Open Box, and Used items are subject to a 7-day trial period.

Is there anything that you guys won’t take back or that does not apply to your return policy?

We definitely want to work with you and be as flexible as we can to earn your business and to make sure you’re happy with everything you purchase from us. Unfortunately, there are some things that we simply cannot take back once it’s sold. That includes:

  • Custom orders or instruments with modifications (pickup installs, straplock installs, tuner installs, etc)
  • Software or authorization keys
  • Guitar amp tubes or cabinet speakers
  • Pickups that have been installed
  • Strings that have been installed
  • Drum heads and cymbals that show signs of use
  • Personal items (earphones, harmonicas, instrument mouthpieces, etc.)
  • Turntable cartridges
  • Styli
  • Control vinyl

When sending back a return, please make sure that the return merchandise authorization number (RMA) provided by one of our Gear Experts is clearly written on the label of your return. To help avoid any restocking fees, please don’t write anything on the packaging. Please return all of the original packaging and its contents. We must receive the item/order back in a condition that allows us to resell it in the same condition it was originally in when we sent it out. 

Your return label should look something like this:
Music Store Live
300 W. 28th St, ste 102
National City, CA 91950

(Note: Purchases made through third party marketplaces such as eBay, Reverb, or Amazon have their own policies and criteria for returns. Please ask if you have any questions regarding that process.)

Shipping Policy Details

In most cases we ship new orders out within 1 business day of receiving payment. Here are some things to note:

  • An indirect signature will be required upon delivery for all transactions over $250. If you would like to require a signature on a transaction of less than $250, please request it when you place your order.
  • Your order must ship to the billing address associated with your credit card, PayPal, or other method of payment. If you need to use a shipping address that differs from your billing address, feel free to contact a Music Store Live Gear Expert and we can help you out.
  • If you want the shipment to be held at a shipping company hub it is your responsibility to make those arrangements directly with the shipping company. If you’d like it held at a local FedEx facility, for example, please provide us with the full address of that facility before your order is shipped. This works out better than trying to re-route it once it’s in transit.
  • We do not insure packages valued under $3,000. If you would like to add insurance for delivery please request it when requesting your order. Whether you choose to or not, we will still assume all of the responsibility in getting your item to you safely.
  • Orders shipped within California will be subject to 7.25% state sales tax.

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