---
product_id: 327990512
title: "Musical Fidelity Tube Amplifier & Preamp Board - 6J1 Vacuum Tube, Headphone Amp Kit"
brand: "kuuleyn"
price: "$41.22"
currency: USD
in_stock: true
reviews_count: 13
category: "Kuuleyn"
url: https://www.desertcart.us/products/327990512-musical-fidelity-tube-amplifier-and-preamp-board-6j1-vacuum-tube
store_origin: US
region: United States of America
---

# 6J1 vacuum tube preamp for warm analog sound 8x 470µF capacitors for ultra-clean power DIY kit for hands-on assembly experience Musical Fidelity Tube Amplifier & Preamp Board - 6J1 Vacuum Tube, Headphone Amp Kit

**Brand:** kuuleyn
**Price:** $41.22
**Availability:** ✅ In Stock

## Summary

> 🎶 Elevate your sound game with vintage tube vibes — DIY style!

## Quick Answers

- **What is this?** Musical Fidelity Tube Amplifier & Preamp Board - 6J1 Vacuum Tube, Headphone Amp Kit by kuuleyn
- **How much does it cost?** $41.22 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/327990512-musical-fidelity-tube-amplifier-and-preamp-board-6j1-vacuum-tube)

## Best For

- kuuleyn enthusiasts

## Why This Product

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

## Key Features

- • **Compact & Sleek:** Small footprint (5.12 x 3.94 x 0.98 inches) fits perfectly in any desktop audio rig.
- • **Noise-Free Power:** Eight 470µF capacitors ensure hum-free, crystal-clear audio performance.
- • **Pure Analog Warmth:** 6J1 vacuum tube filters digital harshness for rich, natural sound.
- • **Versatile Power Input:** Supports DC 5.5*2.1 socket or direct AC 12V transformer connection for flexible setup.
- • **Custom Build Experience:** Assemble your own amplifier and own the process of crafting premium sound.

## Overview

The Musical Fidelity Tube Amplifier & Preamp Board features a 6J1 vacuum tube that enhances audio by filtering out digital artifacts, delivering warm and natural sound. Equipped with eight 470µF capacitors, it provides a clean, noise-free power supply. This DIY kit invites audiophiles to build their own amplifier, supporting flexible power options and compact design, perfect for upgrading headphone or line-level audio setups.

## Description

Product description Great for Connect the 6J1 tube pre-amp between sound source and amplifier, it will effectively filter digital flavor, the music and human voice will be relatively good. Features Eight 470UF capacitor filter is very clean, excellent power system to no hum, filaments are powered with DC 12V and need to be connected in series in order to reduce noise. Coupling capacitor is electrodeless electrolytic capacitor with high frequency and low resistance. Please Note Using DC 5.5*2.1 socket and AC 12V transformer, you can also use AC 12V transformer without plug, just need to weld the power cord onto the circuit board. This kit comes in parts so you can assemble them together by yourself, enjoy the process of building your own tube amplifier. Specifications

Review: Muy buen preamp... - Excelente
Review: It works.... sort of - The only instructions you have on this is following the silkscreen on the board. No instructions or schematics. I can't really tell that the volume going in is much different than out even with the volume wide open and a headphone signal with the volume maxed. This might work well to insert line level to add the tube effect but a headphone amp it ain't. The channels are a little off balance but without a schematic or anything I am not sure how to troubleshoot.

## Features

- 【Funtion】: This vacuum tube amplifier can connect the 6J1 tube pre-amp between sound source and amplifier, it will effectively filter digital flavor, the music and human voice will be relatively good.
- 【Eight 470uf Capacitor Filter】: Eight 470UF capacitor filter is very clean, excellent power system to no hum, filaments are powered with DC 12V and need to be connected in series in order to reduce noise.
- 【High Frequency And Low Proof】: The eight 470UF capacitors included in the DIY tube amplifier kit have very clean filtering, and the power system is excellent and noise-free. The filament is powered by DC 12V and needs to be connected in series to reduce noise.
- 【Assemble Yourself】: This diy amplifier kit comes in parts so you can assemble them together by yourself, enjoy the process of building your own tube amplifier.
- 【Easy To Use】: This vacuum tube amplifier uses a DC 5.5*2.1 socket and an AC 12V transformer. You can also use an AC 12V transformer. No plug is needed, just solder the power cord to the circuit board.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08Z3C5YXP |
| Best Sellers Rank | #89,876 in Electronics ( See Top 100 in Electronics ) #547 in Audio Component Amplifiers |
| Brand Name | Kuuleyn |
| Customer Reviews | 3.9 out of 5 stars 47 Reviews |
| Item Dimensions | 5.12 x 3.94 x 0.98 inches |
| Item dimensions L x W x H | 5.12 x 3.94 x 0.98 inches |
| Manufacturer | Kuuleyn |
| Material Type | PCB, tube bases, and materials of 6J1 tubes |
| Maximum Supply Voltage | 12 Volts (AC) |
| Minimum Supply Voltage | 12 Volts (AC) |
| Model | Kuuleynga4ktp5v7w881 |
| Mounting Type | Surface Mount |
| Number of Channels | 2 |
| Part Number | Kuuleynga4ktp5v7w881 |
| Specification Met | FCC |
| Supply Current | 0.8 Amps |
| Unit Count | 2.0 Count |
| Voltage | 12 Volts (AC) |

## Product Details

- **Item dimensions L x W x H:** 5.12 x 3.94 x 0.98 inches
- **Manufacturer:** Kuuleyn
- **Maximum Supply Voltage:** 12 Volts (AC)
- **Minimum Supply Voltage:** 12 Volts (AC)
- **Voltage:** 12 Volts (AC)

## Images

![Musical Fidelity Tube Amplifier & Preamp Board - 6J1 Vacuum Tube, Headphone Amp Kit - Image 1](https://m.media-amazon.com/images/I/71JVI4O9v3L.jpg)

## Questions & Answers

**Q: Does this come with the acrylic case shown in the photos?**
A: No, acrylic case not included

## Customer Reviews

### ⭐⭐⭐⭐⭐ Muy buen preamp...
*by A***N on April 12, 2026*

Excelente

### ⭐⭐⭐ It works.... sort of
*by P***S on June 8, 2024*

The only instructions you have on this is following the silkscreen on the board. No instructions or schematics. I can't really tell that the volume going in is much different than out even with the volume wide open and a headphone signal with the volume maxed. This might work well to insert line level to add the tube effect but a headphone amp it ain't. The channels are a little off balance but without a schematic or anything I am not sure how to troubleshoot.

### ⭐⭐⭐⭐ Good kit, product picture a little misleading
*by J***W on November 5, 2023*

First off the plastic case is sold separately which was a slight bummer. I did end up buying one. I tried running it initially off DC 12v which is what most power adapters are. Was quiet and distorted. Figured out I needed 12v AC and got the correct adapter and it worked. The 2 best cheap mods I have found: Either replacing R14 and R19 with 100ohm resistors or just soldering a 220 ohm resistor on the underside of those supplied two resistors. This slightly opens up the sound stage and raises the volume some. Replacing C10 and C12 with 10uf caps or just bridging the originals with 10uf caps does really help the bass response like another review said. Also getting a matched pair of GE tubes helps improve the sound over the cheap ones supplied. This will cost you about as much as the kit though. With a nice set of headphones this little preamp does sound quite good. That resistor mod to R14/R19 really helped give the volume I wanted on my headphones. They are 40ohm speakers and I doubt you would get near the needed volume on any headphones of much higher resistance.

## Frequently Bought Together

- Tube Amplifier Kit, DIY Tube Preamp Kit, Tube Preamp, DIY Amplifier Kit, 6j1 Vacuum Electron Tube Valve Preamp Tube Amplifie Board Headphone Amp Parts Musical Fidelity Kit DIY Electronic Kits
- Enclosure Protection Parts Kit Tube Preamp Box, Vacuum Tube Preamp Box, for 6J1 Valve Preamp Board

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-07-23*