For sale Pro-Ject Prebox S2 Digital Pre amp and DAC ($325.00 obo). It was my toe in the water for a headphone setup but am happier with my Torii Jr and HDT's! Also for sale is the Sennheiser Pro Audio HD 600 Open Back Professional Headphone ($250.00 obo). Would love to sell as a set but am ok with separating as well. Ill take off $50 if you buy together.

Here are the Specs:

Pro-Ject Prebox S2 Digital:
-dual mono circuitry with two high-performance ESS Sabre DACs (ESS9038Q2M)
-high-res audio playback, including PCM-based files up to 32-bit/768kHz and DSD512
-full hardware-based MQA support
-selectable digital filters
-vanishingly low jitter (as low as 100 Femtoseconds)
Inputs:
1 coaxial digital
1 optical digital (Toslink)
1 USB Type-B for connection to a computer
Outputs:
RCA stereo output (rear-panel)
1 front-panel 1/4" full-sized headphone output

Sennheiser HD 600 Circumaural Headphones Features:
-High-quality, open metal mesh earpiece covers for an extremely transparent sound
-Computer-optimized magnet systems minimize harmonic and intermodulation distortion
-Extremely lightweight aluminum voice coils ensure excellent transient response
-Neodymium ferrous magnet systems for optimum sensitivity and a wide dynamic range
-Exceptionally natural, spatial and accurate sound
-Detachable OFC copper cable, Kevlar-reinforced, with very low handling noise

I can send pictures if interested.

DAC Sold.