Comes with a set of Mullard tubes in it and an extra set of Electro Harmonix 12AX7EH tubes. I don’t have the jumpers for the back I made a set out of a female electro connector and put shrink wrap on it. Works great. The Pro-Ject Tube Box DS2 is a high-quality phono preamplifier designed for home audio systems. It features a Mullard and EH tube design, providing warm and rich sound quality. With its brand reputation and specific model, the Tube Box DS2 is a reliable and desirable choice for audiophiles looking to enhance their audio experience with a classic tube amplifier.
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