The Pro-Ject Tube Box E is a compact valve phono preamplifier from Pro-Ject's E-line of affordable, high-quality audio components. Sitting at the entry point of Pro-Ject's tube-based phono stage range, it brings the warmth and sonic character of valve amplification to a surprisingly compact and accessible package, without any compromise in circuit integrity.
Where many phono stages at this price rely on integrated circuit operational amplifiers, the Tube Box E takes a fully discrete approach, using two ECC83 (12AX7A) valves and a discrete circuit design with no OpAmps throughout the signal path. The result is a clean, low-noise amplification stage with an accurate two-part passive/active RIAA equalisation network. A FET input stage keeps noise to an absolute minimum, while a dual-mono circuit layout maximises channel separation.
The Tube Box E supports both moving magnet (MM) and moving coil (MC) cartridges. Gain is switchable from the front panel, offering 40dB and 43dB for MM cartridges and 50dB, 60dB, and 63dB for MC. A subsonic filter, also on the front panel, cuts rumble below 20Hz at 18dB per octave to prevent bass driver over-excursion with warped records. For cartridge loading, the bottom of the unit provides a wide selection of input impedance and capacitance options, allowing precise matching to your cartridge's requirements.
Construction is in a fully metal enclosure for effective shielding against electromagnetic interference and vibration. The front panel and controls are machined from aluminium. Internal power supply arrangements are extensive, with multiple regulated supplies and a well-filtered high-voltage anode supply. Gold-plated RCA connectors are used throughout. The tubes are user-replaceable, making tube rolling straightforward for those who wish to experiment with different sonic characteristics.
The Tube Box E is available in black or silver to match other components in Pro-Ject's Box Design E series.
