High-End Tube Sound Quality

Tube phono stages have been an integral part of our product portfolio for many years. The latest Tube Box DS3 B adds balanced capability to the mix, making this our first True Balanced tube phono preamp. The design benefits from an outstanding dual-mono circuit layout with discrete components assembled with expertise in Europe. It’s a hybrid design utilizing tubes in the input & gain stages. All electrical components (including the tube output stage) are audiophile-grade, merging to deliver breathtaking sound quality from your turntable & phono cartridge.

Balanced – It’s Almost Unbelievable

Use the 5-pin mini XLR or standard XLR inputs to recruit the balanced circuit in the Tube Box DS3 B. In each channel, balanced audio signals (aka symmetrical) are comprised of hot and cold (or + / -) conductors carrying the same musical information but are inherently out of phase. The (-) signal is an inverted duplicate of the (+). Opposite polarities render them ‘different’ in the eyes of the balanced circuit. The balanced circuit is where common-mode rejection occurs, canceling accrued noise that’s affected each the hot (+) and cold (-) signals (thus the noise is ‘common’ to them). Once the balanced circuit has canceled the ‘common’ noise, the cold (-) signal’s polarity is inverted to match hot (+) one. This amounts to more amplitude (about 6dB), and less noise (about 10dB). You can image the wealth of detail and clarity that surfaces in the absence of the aforementioned noise and with the added amplitude. The difference is not subtle, and once you’ve heard it, there’s no turning back. Hop over to our balanced audio FAQs to learn more!

Two Turntable Inputs, Endless Cartridge Options

Two turntables can be connected simultaneously to the Tube Box DS3 B! The electrical settings for each turntable are easily managed from the front panel and are stored in the memory bank. A range in gain of 40-65dB is at your fingertips. This allows you to cater to your cartridge’s output as well as to the overall level of your audio sources.

Load impedance (aka cartridge loading or input impedance) for MC cartridges is freely adjustable in the range of 10-1000 ohms. A system introduced to the audio industry by Pro-Ject, the potentiometer allows you to seamlessly adjust impedance during playback for on-the-spot evaluation. This is critical to finding the optimal impedance value for your cartridge as it performs in your system.

Additional information
Weight 1.5 kg
Dimensions 22.7 × 20.6 × 9.1 cm



  • Balanced XLR inputs & outputs
  • Balanced mini XLR input
  • Continuously variable cartridge loading
  • Precise RIAA equalization
  • Low-noise, low-distortion circuitry
  • MM & MC capable
  • Single-ended RCA inputs & outputs
  • Dual-mono design
  • Subsonic filter
  • Aluminum chassis shields RF/EMI
  • Available in silver or black
  • Optional magnetic wooden side panels
  • Made in Europe


  • Tubes: 2x 6922/E88CC
  • Input impedance: variable 10-1000Ω/ 47kΩ
  • Input capacitance: 50pF, 150pF, 300pF, 400pF
  • Gain options: 40, 45, 50, 55, 60, 65dB
  • Output voltage (typical at 40dB): 500mV/1kHz output at 5mV/1kHz input
  • Signal/noise ratio (40dB): >92dBV; 102dBV (‘A’ weighted)
  • Signal/noise ratio (60dB): >78dBV; 87dBV (‘A’ weighted)
  • THD at 1 kHz: <0.003% (MM), <0.02% (MC)
  • THD (20Hz-20kHz): <0.005% (MM), <0.03% (MC)
  • RIAA-equalization curve accuracy: 20Hz-20kHz (±0.5dB)
  • Subsonic filter: at 20Hz with 18dB/octave
  • Inputs: RCA, XLR, Mini XLR
  • Outputs: RCA, XLR
  • Trigger in/out: 12V (2.5mm jack)
  • XLR wiring: 1=ground, 2=hot, 3=cold
  • Outboard power supply: 18V/1000mA DC
  • Power consumption: 18V max, 750mA DC, <0.5W in standby
  • Dimensions (WxHxD): 206 x 91 x 227mm
  • Dimensions (standard): 8.11 x 3.54 x 8.94”
  • Mass (weight): 1560g (3.44 lbs)