Tube Boxes have been an integral part of ProJectAudio's product portfolio for many years. Now, the new Tube Box DS3 B adds balanced in - and outputs to tube amplification.

This precision tube phono preamplifier benefits from outstanding circuit technology from Dr. Sykora and uses ultimate components.

Cartridge Loading Options

You can connect two turntables at the same time & easily set everything on the front plate. Input settings are stored in the memory and ranges from 40dB up to 65dB are possible. You can perfectly match the Tube Box DS3 B with a wide variety of cartridges and integrate it into the rest of your hi-fi system, matching the volume levels accurately to other sources like CD players or streaming devices.

Load impedance can be set continuously via potentiometer, a system developed by ProJect Audio Systems. This allows you to seamlessly adjust the impedance during playback and immediately assess the impact of different loading options and is necessary to find just the right load impedance for your cartridge.

No other manufacturers implement this feature in this way.

Balanced Signal Transmission

Connect your turntable either with the 5-pin mini XLR cable or standard XLR cables & profit from the balanced signal transmission. Symmetrical - also called balanced - transmissions consist of a hot and a cold (also called + and -) signal. Both signal chains effectively carry the same musical information.

ProJect Tube Box DS3 B can extract the final musical information out of the +/- signals and remove all noise that was potentially added along the transmission. All components including tube output and polypropylene capacitors are audiophile grade and guarantee a breathtaking sound experience.

Product Features

• Balanced XLR - Interference free
• E88CC Vacuum Tubes
• Settings - Continuously impedance loading
• Low ESR capacitors
• Available in black or silver
• Handmade in Europe from high quality materials

Technical Specifications

Tube assembly
2x E88CC / 6922

Input impedance
Stepless 10-1000 Ohms, fix 47 kOhms

Capacitance
50 / 150 / 300 / 400 pF

Gain (+6dB using XLR Out)
40 / 45 / 50 / 55 / 60 / 65 dB

Output voltage typically
500 mV/1kHz at 5mV/1kHz (at 40dB)

Signal-to-noise ratio
>87dBV -, A weighted

THD
< 0,03%

RIAA curve accuracy
+/- 0,5dB/20Hz - 20kHz

Subsonic filter
at 20Hz with 18dB/octave

Input
1x 5-pin mini XLR 
1x pair XLR
1x pair RCA phono

Output
1x pair RCA
1x pair XLR

Power supply
18V/1000mA DC

Power consumption
max 750 mA DC / < 0,5 watt standby

Dimensions (W x H x D)
206 x 70 x 194 mm