Fender Pro Junior Modifications

$ 93.95

Unleash the tone of your Pro Jr with the Supreme Mod Kit from Fromel Electronics!  

The Fender Pro Jr is a great value and a good sounding little amp, and with a little help can be a GREAT little amp.  These mods will make your amp more reliable, have less noise and better tone. If you want a total tonal transformation, this is the mod kit for you, it replaces every cap and resistor in the signal path with Sprague, Orange Drops and WIMA boxes for higher value caps, Silver Mica's for smaller value caps and 1% 1/2 Watt metal film resistors for Low Noise and Precision performance.

Additionally, the recap kit upgrades every tone-critical electrolytic cap in the circuit with high quality F&T and Nichicon electrolytic caps.  All the capacitors in this kit were specially chosen for great tone, reliability, and accurate fit in your Pro Jr.

Please Note:The Supreme Mod kit includes both the "Complete Mod Kit" and "Recap Kit" that we offer and is the ultimate tonal upgrade for your own amplifier!

"Have us Install" price includes parts and labor. We will bill you return shipping upon installation completion and which will be comparable to the cost of shipping it in. You can view USPS Parcel Select shipping rates HERE . Since we're located in the Pacific Northwest you can calculate shipping cost by how many zones it crosses to reach us from where you ship it from.

Click here for info about sending your amp in for modification.

Included in the kit is all the components necessary to to get your amp in top shape and the detailed instructions to make the changes easy. If you have a basic understanding of electronics and soldering skills you can do these mods in a couple of hours.  Included in this kit are the following upgrades:

Tone Stack - Replace the wimpy Bass and Mid caps with high quality caps with corrected values to open up the tone and get rid of that boxy sound. What about the Treble cap, replace the ceramic cap with a high quality Silver Mica cap. The adjusted value shifts the mids up very slightly, the result is an amp that sounds huge and warm, not boxy and thin.

Power Stiffening - Doubles the capacitance in the first filter stage, this reduces hum and increases reserve power for solid bass and strong picking, This mod gives the amp the extra torque it needs to push through strong when you are playing hard.

Cooler Bias - You are cooking the output tubes in your amp. This mod lets the amp run cooler without sacrificing tone or drilling holes in your PCB. Your tubes should live a long and happy life after this mod. I include a new bias resistor that sets the idle on the tubes to about 8.5w which is right where it should be.

Switchcraft Input Jack - Your input jack is soldered directly to the circuit board, apply some tension when the amp is plugged in and you could cause major damage to the circuit board in the amp. This mod gets rid of the wimpy plastic input jack and replaces it with a high quality enclosed switchcraft jack that is panel mounted and NOT directly soldered to the circuit board. Included is a shoulder washer and isolation washer so the input jack does not ground directly to the chassis and prevents ground loops. The jack comes with high quality pre-tinned color coded leads for easy installation. 

Proper Lead Dress - Take a look inside a boutique tube amp and you will see all the wires carefully twisted and placed for greatest reduction in oscillation and noise. The Pro Jr has all the internal wires zip tied together. I give clear instructions on dressing the leads inside the amp for optimal performance, this results in lower noise and less chance for oscillation.

Electrolytic Cap Upgrade - replaces all of the caps in the circuit chain with new and upgrades parts.  Older Pro Jr’s that are made in the USA are all getting due to have their filter caps replaced and many of the current Pro Juniors made in Mexico are known to have leaky filter caps. The Fromel kit rectifies these issues.

WARNING: Performing these modifications WILL void the warranty on your amplifier. Working on amps can be deadly if you do not take proper precautions. Follow these instructions very carefully. If you are at all unsure of your ability to perform these modifications STOP and take your amp to a professional to be modified. You can also send your amp to me for modification.

No Warranty: This kit and the instructions included do not include any warranty of any kind. The modifications to your amplifier are at your own risk and you agree to completely hold harmless the seller of this kit against any and all claims. Tube amplifiers contain parts that operate at very high temperatures and deadly voltages. If you are not sure of your abilities to perform these modifications then do not perform them.


Available for international shipping, International shipments, especially to EU can take up to 4 weeks because of customs

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