One Control BJF Series 4K Lemon Yellow Compressor Pedal

by One Control

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  • One Control BJF Series 4K Lemon Yellow Compressor Pedal

    What do musicians look for in an effect called a compressor? Crispness of the tone and percussive elements for a bassist, enhanced sustain for slide playing or a booster for solos with guitars, an enhancing effect for acoustic guitars and other instruments, or recreating the tones of legendary vintage pedals and studio rack gear. Compressors can be used in a variety of ways depending on the style of music and the instrument. Despite the differences there are several compressors that can be called true classics. Famed pedal designer Björn Juhl has created several classic compressor designs over the years, and all of them have a musical and three-dimensional quality that has been referred to by players as “magical” and “beautiful”. Our latest compressor is the LEMON YELLOW COMPRESSOR 4K and has been designed by BJF for One Control.

    The role of a compressor is very simple – compress signals above a certain level and amplify signal below a certain level. However, with these two basic concepts there are a wide range of compression styles and sounds that can be created. When discussing typical effects pedal based compressors that are either natural sounding or quite effective and obvious sounding. BJF has always designed compressors to be both beautiful and natural sounding with the clear tones one would get with high-end rack equipment. The LYC4K has been designed to have the three-dimensional warmth of a vintage studio rack compressor while still being able to easily be controlled like a standard compressor pedal. The sounds you can create with the LEMON YELLOW will make you wonder how we got all that studio gear into such a small pedal.

    While some compressor pedals will take over your tone and can make it seem smaller, the LYC4K has been especially designed to be effective while maintaining your natural tone – this sense of balance between the elements of “natural” and “effective” qualities is at the heart of our compressor pedal.

    The controls for the LYC4K start with GAIN and VOLUME – if you raise the GAIN the overall compression will be stronger, while if the VOLUME level is raised the LYC can be used as a full-scale clean booster or a level cut/limiter type of effect. With an output of up to +18dB, you can use the LYC to boost the input levels of the rest of your signal chain, stacking with other distortion pedals or an already overdriven amplifier. The LYC can add just a touch or a heavier compression while boosting your favorite signal chain. The ratio of compression can vary from 1:1 to 5:1 and always has that clear, natural tone – but if you set the ratio and gain to maximum, you can have a light overdrive tone with fantastic dynamics. You can also use the LYC to adjust the forcefulness and attack of your entire signal chain at the end.

    We have also added a BLEND knob to make sure you have as much or as little of the LEMON YELLOW in your tone as you desire. You can focus on the attack transients of your sound – or take it to the ultimate in sustain and compression. Use the BLEND knob to help adjust your tone and keep it clean and noise free. The clean tones mad with single coil-based guitars are beautiful, but they also need some help due to lower output and tonal character. By using the LYC4K you can easily create beautiful tones that make you want to play forever by adding the strength of tone, sustain, three-dimensional sound that envelopes your ears and fingers, and a little glitter on top. With humbuckers or high output pickups, the LYC4K can add a firmer tonal foundation to your tone making it easier and tighter sounding without changing the tone itself. The stability of tone and feel that the LYC4K can give brings peace of mind to guitarists.

    Compressors are also said to be essential for slide guitar style playing. Among slide guitarists, there are many that are looking for a compressor that can naturally sustain the sound without degrading the tone – the LEMON YELLOW COMPRESSOR 4K will be one of the ideal compressors for such a task.

    Bassists also want a natural compressor that doesn’t alter the natural bass tone – the LYC4K can easily create a sound that makes use of the original tone of the bass from its natural and clean sound by using the BLEND knob – and create unique and overdriven sounds by increasing the RATIO and GAIN.

    As usual, our mini-sized anodized aluminum housing has all this technology in a small footprint, with our excellent manufacturing and heavy-duty parts selection. Even as small as the LYC4K is, you can still use a battery when needed. Get all your compressor needs met with the LEMON YELLOW COMPRESSOR 4K

    Björn’s take:

    “LEMON YELLOW COMPRESSOR 4K (LYC4Kn) is a particularly natural compressor. You will be able to experience an illusion that does not lose its clearness even in loud play. It will be a great presence in slide play. In SUSTAIN mode, you can easily express the play nuances so that you forget you are applying the compressor”

    From Kaz:

    “After the longest development period in One Control history, our LEMON YELLOW COMPRESSOR 4K is ready. The first prototype was a very simple one-knob design that we all liked but was still not good enough. After some improvements, we had a two-knob prototype that I really felt was ready to be a product, but we continued develop. The completed three-knob + switch version was finally completed and released.

    When you reach for the heights and have a distant goal, every step counts. What we were seeking was not bound by knowledge or common sense, but only by our own vision. We spent much time trying to understand the sounds correctly. And the LYC4K has completely overcome the size versus quality barrier. You can play an elegant and professional sound like the studio rack-mount compressors, but in a much smaller and easier to use package.


    • VOLUME: Adjusts the volume.
    • BLEND: Adjusts the balance between the compressor and the original sound.
    • RATIO: Adjusts the compression ratio of the compressor.
    • GAIN: Adjusts the strength of the compressor.


    • BJF-designed compressor that creates a clear and natural tone
    • Suitable for various styles due to the operation feeling like a compact pedal
    • You can push the amplifier and use it as a booster Level control
    • Overdrive-like from the clearness of studio equipment
    • High-quality mini-sized case machined from aluminum
    • Built-in battery is also possible
    • True bypass switching

    One Control BJF Series 4K Lemon Yellow Compressor Pedal Features:


    • Input impedance: 500K
    • Output impedance: 10K
    • Drive voltage: 9V
    • Current consumption: 10mA
    • S / N ratio: -80dB
    • size: 39Wx100Dx31H mm (excluding protrusions)

    47Wx100Dx48H mm (including protrusions)

    • Weight: Approximately 160 grams (200 grams when battery is inserted)
    • Batteries are not included.
  • We want you to feel confident with your Prymaxe purchase, which is why when you purchase a new product from us, you are automatically enrolled into our FREE Two Year Warranty.* 


    What is covered:

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    * We reserve the right to end this promotion at any time.


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  • 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

    45-Day Satisfaction Guarantee

    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.  

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    What is NOT Returnable:

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    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.

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    There are a number of reasons your package could be refused by us, including:

    • It was a new/demo item received outside of the 45-day window
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    • The item shows signs of wear
    • The original product box was damaged or written on/the item was packaged in a separate shipping box

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