---
product_id: 101398680
title: "FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver)"
brand: "fx-audio-"
price: "VT4528"
currency: VUV
in_stock: true
reviews_count: 9
url: https://www.desertcart.vu/products/101398680-fx-audio-tube-03-tube-preamplifier-6k4-tube-hi-fi
store_origin: VU
region: Vanuatu
---

# 6K4 Tube NE5532 Chip Bass & Treble Control FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver)

**Brand:** fx-audio-
**Price:** VT4528
**Availability:** ✅ In Stock

## Summary

> 🎧 Elevate Your Listening Game with the FX-AUDIO TUBE-03!

## Quick Answers

- **What is this?** FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) by fx-audio-
- **How much does it cost?** VT4528 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.vu](https://www.desertcart.vu/products/101398680-fx-audio-tube-03-tube-preamplifier-6k4-tube-hi-fi)

## Best For

- fx-audio- enthusiasts

## Why This Product

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

## Key Features

- • **Complete Package:** Includes everything you need for an audiophile experience right out of the box.
- • **Unleash Your Sound:** Experience the rich, dynamic audio of the 6K4 vacuum tube.
- • **Premium Build Quality:** Enjoy high-performance sound with a solid aluminum alloy design.
- • **Versatile Connectivity:** Easily connect to all your favorite devices with RCA inputs and outputs.
- • **Tailored Audio Experience:** Fine-tune your music with independent bass and treble controls.

## Overview

The FX-AUDIO TUBE-03 is a high-fidelity tube preamplifier featuring a 6K4 vacuum tube and NE5532 operational amplifier, designed for audiophiles and beginners alike. With independent bass and treble controls, RCA connectivity, and a premium aluminum alloy build, it delivers a rich sound experience while ensuring stable signal transmission. The package includes essential accessories and a 12-month warranty.

## Description

Full description not available

## Features

- 【6K4 Tube and NE5532 Chips】 This TUBE-03 tube preamplifier is equipped with triodes 6K4 vacuum tube and NE5532 OP IC. The vacuum tubes give you a different acoustic enjoyment with dynamic, sweet tube sound enjoyment. This 6K4 vacuum & valve tube is replaceable with 6J1, GE5654. OP chip NE5532 can be replaced by AD827JN / MUSE02
- 【Bass & Treble Control】 The vacuum tube preamplifier has independent bass knob, treble knob, and main volume knob. It ensures more delicate adjustment of music to achieve pleasant sound quality according to your preference. It is a great choice for both audiophile and starters
- 【RCA Input & Output】 RCA input can connect to smartphone, computer, CD, DVD, MP3, TV, blu-ray players. RCA output can connect to active speaker, or amplifier + passive speaker (can not connect passive speaker directly). RCA cable comes with package
- 【Premium Material】 Solid and textured aluminum alloy oxidation wiredrawing shell, black immersion gold PCB sheet and gold-plated interface ensures more stable signal transmission, high-temperature resistance. High performance component will bring high quality listening experience, low noise and pure sound
- 【Packing Lists】 Package includes 1 x tube preamp, 2 x 6K4 tubes, 1 x 12V 1A power supply, 1 x RCA cable, 1 x user manual, 1 x warranty card. Comes with 12-month guarantee.This is a preamplifier, not a power amplifier or phono preamp. Not for turntables or car audio

## Product Details

- **Item dimensions L x W x H:** 3.74 x 4.72 x 1.18 inches
- **Voltage:** 12 Volts (DC)
- **Manufacturer:** FX-AUDIO-
- **Maximum Supply Voltage:** 12 Volts (DC)
- **Minimum Supply Voltage:** 12 Volts (DC)

## Images

![FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) - Image 1](https://m.media-amazon.com/images/I/61dfzbFv8xL.jpg)
![FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) - Image 2](https://m.media-amazon.com/images/I/61CD9dfsP+L.jpg)
![FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) - Image 3](https://m.media-amazon.com/images/I/61rtn9lx4iL.jpg)
![FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) - Image 4](https://m.media-amazon.com/images/I/71H2V-Vz0KL.jpg)
![FX-AUDIO TUBE-03 Tube Preamplifier 6K4 Tube Hi-Fi Tube Preamp with Bass & Treble Control Home Theater Stereo Audio Preamplifier DC 12V (Silver) - Image 5](https://m.media-amazon.com/images/I/61GgGKM0UFL.jpg)

## Available Options

This product comes in different **Color** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars







  
  
    Amazing.
  

*by G***L on Reviewed in the United States on May 22, 2021*

I decided to write a proper review for this device because it's definitely worth more than the price.First off, the quality seems very good.  Potientiometer knobs are the click-style, which I personally like.  They really add a vintage feel to the tiny unit.This little preamp gives big sound.  Listening to music through this is a lot like playing your music through a mint 1950s jukebox.  It adds depth, tons of bass and has a nice treble tone.Right now, I'm running this preamp, a vintage Sony STR-1800 receiver, which is rated at a measly 12 watts of old-school power paired with Infinity Alpha 50 floor standing speakers.  The sound, despite being vastly underpowered is overwhelming.  I can't even imagine what it will sound like being pushed by 50 or more wpc.A note about the tubes:The chinese ones that come with the unit are actually very good in terms of midrange tone.  I did swap them out for a pair of NOS Raytheon 5654s from 1952, but they are comparable to the cheap Chinese tubes that came with the unit in terms of sound.  5654s seem to give a lot more bass, while the 6k4 tubes that came with the unit really open up the midrange.  With the 6k4 tubes, I get a lot more snare and cymbal to go with the rich bass that is provided, while the Raytheon 5654s want to rattle my walls down with the abundance of bass.  My point is that you don't have to worry about changing the tubes.  For rock music, the 6k4 tubes were superior to the 5654s.  But the 5654s seem to love electronic music and rap.  Just some food for thought.All in all, this unit is a great starting point for the beginning audiophile.  Before you go buying a $1,200 hifi tube amp, this is a nice introduction to show what tubes can do for your system.  I highly recommend it and I will be buying more tube amplifiers and components.

### ⭐⭐⭐⭐ 4.0 out of 5 stars







  
  
    A good bargain ,worth experimenting with
  

*by J***W on Reviewed in the United States on September 27, 2018*

edit: ive only used $20 dacs and after some research the schiit modi 3 is probably a better tweak under 100 if you dont have a comparable dac. this preamp does not add detail over all but may emphasis certain frequencies allowing things to pop out that were hidden before as well as some warmth although to a degree it can make things a bit cloudy or even chaotic. The best remedy for this is going with a ef93 over any 5654 type. Helps remove some harshness from digital. Worth a try, I recommend good quality ef93 (6k4) like a seimens over ANY 5654, ive tested them all, and the suca audio tube preamp for the same price is more accurate sacrificing less OVERALL detail loss and overall sounds better.If this does its job you should get a less edgy digital music experience with more warmth and its nice to play with it on sometimes, sometimes off.I think i was wrong when i said it didnt emphasis certain frequencies which i realized when my speaker placement became much better. I think what may be ideal for most of us is a true tube line buffer with no volume or tone controls. theres some x10-d assembled clones for the same price that will probably allow for no detail loss or overemphasis of frequencies, but make digital sound nicer without the sacrifice you get with using one of these tube pres. Thats probably the best option under 100 for a tube buffer until you go up to the $400 ifi tube.previous:  was looking for a volume control for my harman kardon pa2100 power amp. This fits the bill. I run out from the computer with a m audio- audiophile 192 soundcard ->tube 03->pa2100. If you have a decent soundcard like the one I have, I think you'll get more mileage out of this then a sub 100 dollar dac. It gives a liveness to the music, and adds clarity to the vocals I couldn't hear using my Harman Kardon 3250 as a preamp. I'm hearing details I haven't heard before in songs without an exxageration of certain frequencies. It sounds good with the treble at bass controls at the noon, uncolored setting. With my previous preamp I was often unsatisfied in the default bass and treble positions because some level of detail I was used to hearing or wanted to hear was missing. The mids are more present with this.Tube rolling does make a significant difference. I haven't tried the tubes shipped, but had some old sylvania 5654. They  had a hiss with the treble all the way up but colorful and round with good instrument seperation and a good sounding bass. Some old RCA blackplates, had no hiss with treble all the way up. The rca's are more neutral.Btw if you're listening from  your pc, Tidal music service is unbeatable imo for high quality sound. Doesn't quite compare to a good cd player and cds on my setup, but not bad, especially if I bump the treble up on the tube 03 up slightly.I think it's worth a try, especially since you can return it if not happy. I have no hiss with the right tubes, a better preamp than an av receiver can offer, and tube liveness while retaining the output and spl my power amp can provide. For $50 dollars, it's probably the best upgrade I could achieve, for even double the price.

### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars







  
  
    Impressive little preamp!
  

*by J***. on Reviewed in the United States on April 8, 2021*

First off, I would recommend highly for anyone buying this preamp to spend the extra $15ish dollars to upgrade the tubes to GE's 5640.  If possible, get the "Jan" tubes, a real upgrade, IMHO.  This is actually the second of these I have purchased and this one I'm pairing with the Nobsound 6P1 amp.This adds a little extra power to whatever amp you're pairing it with, and having the bass and treble control is a great option, too.  Another nice feature is the detented volume knob, which, anyone into stereo equipment should appreciate, particularly when using something new.It really does open up the sound, IMO, though, and I've paired it with a solid state amp and was very happy with the results.  In fact, this preamp is what got me into tube amps in the first place.  Curse you, for that!Finally, and again this is my own experience owning two of these units, is that it makes a really loud, disconcerting disconnect noise when turning off the power.  It does not seem to affect any of the equipment to which I have it connected, and it takes about a week to two for it to start to go away.  I've coated the inside of these with Deoxit, I've noticed no distortion with the music, and it doesn't seem to be harming any other equipment, so it must just be something "burning in" in the unit.At this price point, I would recommend this to anyone and everyone interested in hearing what a tube sound can do for your listening experience, particularly with digital music.

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*Product available on Desertcart Vanuatu*
*Store origin: VU*
*Last updated: 2026-01-29*