---
product_id: 121343423
title: "COOCHEER Blues Jr. / Pro Jr. JJ Tube Upgrade Kit (2x EL84, 3x 12AX7)"
brand: "coocheer"
price: "€ 262.43"
currency: EUR
in_stock: true
reviews_count: 5
category: "Coocheer"
url: https://www.desertcart.sk/products/121343423-coocheer-blues-jr-pro-jr-jj-tube-upgrade-kit-2x
store_origin: SK
region: Slovakia
---

# Apex matched for optimal tone 2x T-EL84-JJ matched power tubes 3x T-12AX7-S-JJ preamp tubes COOCHEER Blues Jr. / Pro Jr. JJ Tube Upgrade Kit (2x EL84, 3x 12AX7)

**Brand:** coocheer
**Price:** € 262.43
**Availability:** ✅ In Stock

## Summary

> 🎶 Unlock your amp’s soul with the ultimate tube upgrade!

## Quick Answers

- **What is this?** COOCHEER Blues Jr. / Pro Jr. JJ Tube Upgrade Kit (2x EL84, 3x 12AX7) by coocheer
- **How much does it cost?** € 262.43 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.sk](https://www.desertcart.sk/products/121343423-coocheer-blues-jr-pro-jr-jj-tube-upgrade-kit-2x)

## Best For

- coocheer enthusiasts

## Why This Product

- Trusted coocheer brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Trusted by Pros:** Join thousands of musicians who swear by this tube upgrade for authentic sound.
- • **Plug & Play Upgrade:** Easy installation for instant sonic transformation in your Blues Jr. or Pro Jr.
- • **Pure Vintage Warmth:** Experience rich, warm tones that breathe life into every note.
- • **Enhanced Gain Clarity:** Clean up your overdrive and fuzz pedals with superior tube gain control.
- • **Precision Matched Tubes:** Apex matched EL84 tubes ensure consistent, reliable performance.

## Overview

The COOCHEER Blues Jr. / Pro Jr. JJ Tube Upgrade Kit includes three T-12AX7-S-JJ preamp tubes and two apex matched T-EL84-JJ power tubes, designed to deliver warmer, clearer, and more dynamic tones. This kit enhances gain clarity and tonal warmth, making it a perfect plug-and-play upgrade for Blues Jr. and Pro Jr. amplifiers, favored by musicians seeking authentic vintage sound with reliable performance.

## Description

(3) T-12AX7-S-JJ (1) T-EL84-JJ-MP (Apex Matched), which includes:(2) T-EL84-JJ (2) T-EL84-JJ

Review: I popped these into my amp and noticed an immediate difference. The gain from my amp, my overdrive pedals, and my fuzz pedal were super cleaned up and sounded awesome. That said, these seem to be either warmer tubes or "not as high gain" as the original Groove Tubes - which for me was a happy accident. They sound AMAZING! The much needed warmth that the previous tubes didn't have. By the way, get your tubes from Tonal Tubes! They match the tubes for you and ship extremely fast.
Review: That sound is back, you know what I'm talking about. That sound that just pulls the notes right out of your soul. Great set of tubes. Checked them on my tube tester before installation and biasing and they tested as expected.

## Features

- (3) T-12AX7-S-JJ
- (1) T-EL84-JJ-MP (Apex Matched), which includes:(2) T-EL84-JJ

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B00EJXZIP6 |
| Batteries Included | No |
| Batteries required | No |
| Best Sellers Rank | 69,311 in Musical Instruments & DJ ( See Top 100 in Musical Instruments & DJ ) 310 in Amplifier Accessories |
| Customer Reviews | 4.6 4.6 out of 5 stars (302) |
| Date First Available | 6 Feb. 2014 |
| Item Weight | 68 g |
| Item model number | 4308828235 |
| Product Dimensions | 17.78 x 12.7 x 17.78 cm; 68 g |
| Quantity | 1 |
| Volume | 245 Cubic Inches |

## Images

![COOCHEER Blues Jr. / Pro Jr. JJ Tube Upgrade Kit (2x EL84, 3x 12AX7) - Image 1](https://m.media-amazon.com/images/I/71ebOnfI2wL.jpg)

## Questions & Answers

**Q: Will this set work in a vox ac15?**
A: If your amp requires 3x12AX7's and 2x EL84's then this set will work perfectly.

**Q: Who or what is tesla?  this was previously listed as a jj set, now it says jj/tesla.**
A: Nikola Tesla was an inventor, electrical engineer, mechanical engineer best known for his contributions to the design of modern alternating current. How JJ co-opted his name is unknown to me.  As for the tubes I am not a fan.  I tried them several times in different amps and beyond those suffering infant mortality (nearly immediate failure) I found them to be short lived overall.  I pretty much stick with TAD (Tube Amp Doctor) tubes these days. They sound good and the failure rate is very low.  Strictly my opinion, but I hope it helps you with your decision.

**Q: this set fits on a laney cub 12r?**
A: Yes

**Q: Will these work for a blues junior 1?**
A: They work and still do, a 12AX7was bad, so bought a set ans have new extras, different valve/tubes. they work fine

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by R***N on 3 April 2020*

I popped these into my amp and noticed an immediate difference. The gain from my amp, my overdrive pedals, and my fuzz pedal were super cleaned up and sounded awesome. That said, these seem to be either warmer tubes or "not as high gain" as the original Groove Tubes - which for me was a happy accident. They sound AMAZING! The much needed warmth that the previous tubes didn't have. By the way, get your tubes from Tonal Tubes! They match the tubes for you and ship extremely fast.

### ⭐⭐⭐⭐⭐ Review
*by P***L on 2 October 2024*

That sound is back, you know what I'm talking about. That sound that just pulls the notes right out of your soul. Great set of tubes. Checked them on my tube tester before installation and biasing and they tested as expected.

### ⭐⭐⭐⭐⭐ Review
*by R***A on 10 August 2025*

Excelente producto, llegó rápido y excelente precio

## Frequently Bought Together

- Blues Jr. / Pro Jr. JJ Tube Upgrade Kit (2x EL84, 3x 12AX7)
- JJ Electronics Amplifier Tube (T-12AT7-JJ)
- 12AX7 / ECC83 - JJ Electronics, Pin Type: Regular, package of 4

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*Product available on Desertcart Slovakia*
*Store origin: SK*
*Last updated: 2026-02-18*