With original late-70s Op-Amp Big Muffs selling for exorbitant prices, Mike Matthews decided to take the power to the people and reissue the classic pedal at a price that players could afford! The circuitry of the new Op-Amp Big Muff —sometimes also referred to as the IC or V4 Big Muff— has been faithfully re-created while several practical enhancements have been added including a compact, die-cast chassis
The Op-Amp Big Muff Pi features standard controls: Sustain, Tone
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Pre-Orders typically ship with 2 weeks. In the event a product is backordered we will contact you with an exact shipping timeframe.
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What if my package gets stolen?
Please note: We are a small, family owned business. While we want to make sure you are satisfied with your purchase, we would like to try to limit the amount of returns as much as possible. This helps both us and the customer save time and money. If you are unsure about a product, please contact us before you complete the purchase, and we'll do our best to find the item that will best suit your needs. Prymaxe reserves the right to define abuse of the return policy on a case by case basis and consequently refuse subsequent return requests by said abuser and place them "All Sales Final".
Last Updated: October 04, 2022
If you are not 100% satisfied with your purchase, you can return it within 45 days of the original purchase date for a store credit refund, or within 14 days of the original purchase date for a refund to the original purchase method (PayPal, credit card, etc). If an item is not received by us within the 45-day window, the package will be refused. All new items returned must be in BRAND NEW condition with zero signs of wear or use and must be returned in the original packaging with ALL materials (free/bundled items -- must be unused/unopened, warranty cards, plastic, pouches, manuals etc.).
Our 45-Day Satisfaction Guarantee covers brand new products only -- it does not cover used and clearance products (see below). It also does not cover items in the “What is NOT Returnable” list below. Please note: All actual shipping fees paid by Prymaxe will be deducted from your refund along with a 10% restocking fee. This includes orders that qualified for free or subsidized shipping. Return shipping must be paid by the buyer. If you received a defective or incorrect item, please see our FAQ section below.
All Used and Vintage items come with a 48 hour approval period. Please contact us directly at firstname.lastname@example.org within 48 hours of receiving your product for us to set up a manual return for you. Be sure to include your order number and reason for return in the email. All Used/Vintage items must be returned in the same condition they were sent to you in, as well as include all materials that came with it.
All returns should be insured by the buyer and sent via UPS, Fedex, or USPS with tracking. Please do not write on or attach tape or labels to the product box (these will be refused) -- use a packing box to return the product. Attach a shipping label with the RMA number onto the shipping box. Packages without a valid RMA number on the outside of the box will be refused.
To request an RMA number, please email email@example.com. We do not issue RMA by phone.
When will I get my refund?
Once your return is received by us, your refund will typically be processed within 10-15 business days. It typically takes a few business days for all credit card refunds to be processed and reflected on your statement. This means it will take a few extra days for your refund to show in your account after your return is processed. Store credit refunds will be given in the form of a e-gift card which will be available for immediate use after it is emailed to you. Please note: All actual shipping fees paid by Prymaxe will be deducted from your refund. This includes orders that qualified for free or subsidized shipping. Return shipping must be paid by the buyer. If you received a defective or incorrect item, please see the next question.
What if I receive a defective or incorrect item?
If a product is defective upon arrival, or the wrong item was received, all the shipping fees will be covered by us and we will send you a replacement once the original item is received. If for any reason a replacement wont be available for a significant amount of time, we will issue you a store credit to use on another item. For defective items, Prymaxe reserves the right to refuse the return if we determine the reason for the unit failing was not covered under the warranty (i.e., if the item was damaged due to user fault or error). If you feel your item was damaged in shipping, please take plenty of pictures of the damaged box and item and immediately contact us so we can open a claim with the shipping company.
Please be very diligent with testing your defective item. Be sure to try other guitars, power supplies, cables, and amps. We also request that you take a video of the item not working. If we receive your item, test it, and find it to be working, we will give you a refund minus the cost of shipping both ways and charge a 20% restocking fee.
When must I ship my return?
Your return must be received by us within 45 days of the original purchase date for store credit, or postmarked by 14 days for a refund to the original purchase method (PayPal, credit card, etc). This means you must ship your return with enough time for us to receive the package within the deadline. If it does not arrive within 45 days, we will refuse the package. If you feel you sent the package within a reasonable time frame, but it arrived late due to the shipping company’s error, please immediately contact us to make an appeal before we refuse the package.
What if I pre-ordered an item?
If a pre-ordered item arrives outside of the 45 day window from when you ordered it, you will have 7 days from the arrival date to send it back for store credit.
Why was my package refused?
There are a number of reasons your package could be refused by us, including:
I love it when you first punch out a few riffs with a new pedal and it immediately brings a smile to your face.
The OP Amp Big Muff is one such pedal.
One of my favorite Fuzz pedals. Lots of saturation. Sounds just like the pumpkins album.
This my first EHX Muff, I generally play with less distortion but wanted to try out this Op-Amp version. Sound is great, build quality is typical EHX top notch, and the small format fits nicely on smaller pedalboards. Only docking one star because frankly, it's not a very versatile pedal - pretty much wants to be played with all the dials turned all the way up driving a big ol Marshall, but anyone looking at this pedal is probably just after that one sound!
Everything as expected. Listen to the reviews on YouTube. If you like that sound, you’ll love it. If you don’t like that sound, don’t buy it.
Siamese dream is why I learned to play guitar. This definitely has that sound. I've bought many boutique op-amp fuzzes prior to the release of this EHX series and now I feel bad, because this gets you there at less than $100. Worth it.