The FX-Audio TUBE-03E is a 6K4 tube preamplifier. Affordable, it remains a very good preamplifier, complete and powerful, with a clean volume control. In addition to the classic RCA Stereo and 3.5mm Jack inputs, it also includes a 4.2 Bluetooth input for streaming audio files from a device connected to Bluetooth, such as a smartphone. The DAC in charge of digital-to-analog conversion is directly integrated into the Bluetooth A64215 chip and allows decoding of the quality signal. On the output side there is a Stereo RCA. All connectors are gold plated, ensuring very good conductivity and resistance to oxidation. Finally, there is a tone control on the front panel, which allows you to adjust the bass and treble reproduction according to your listening and audio system.

The tone control uses two N5532P AOPs mounted on DIO8 and interchangeable.
Caution! Be careful when changing these components, as any improper handling that damages the device or OPA will void the warranty.