The Manley TUBE DIRECT INTERFACE models feature exceptionally clean and quiet tube circuits which will warm up any electric guitar, bass, violin, and especially those sterile sounding synths. Unique with the Manley Tube DI's is the added 5-position high pass shelf EQ, there to fight unwanted resonances. As splitter devices, the transformer-coupled balanced XLR output can be sent directly to a mic level input, such as through your console channel, while the 1/4" output drives the guitar amplifier cabinet which can be miked and mixed with the direct feed. Low impedance outputs, Ground lift and Console Out Boost switches make these units both versatile and compatible. Keep your Manley DI close at hand to get that noisy high impedance guitar cable into quiet lo-Z territory fast!

We offered both Mono Single Channel and Stereo 2-channel versions.




  • Vacuum Tube: 5751
  • Gain: -6dB or -26dB
  • Input Z: 10 megOhm to 1 megOhm
  • Output Z: 150 Ohm xfmr
  • Frequency response: 12 Hz - 15KHz (-3dB)
  • EQ: LF rolloff -3dB points: 12, 42, 100, 250Hz
  • Transformer-Coupled Balanced XLR Output
  • Console Out Boost Switch
  • Ground Lift Switch
  • Factory set for 100V, 120V or 220-240VAC operation for original destination country's mains voltage.
  • Operating Mains Voltage changeable with power transformer re-wiring and fuse value change.
  • Mains Voltage Frequency: 50~ 60Hz
  • Mains power consumption Mono Tube DI: 
    • 0.050 Amps (50 milliamps = 50mA) @ 120V = 6 Watts
    • 0.025 Amps (25 milliamps = 25mA) @ 240V = 6 Watts
  • Mains power consumption Stereo Tube DI: 
    • 0.0750 Amps (75 milliamps = 75mA) @ 120V = 9 Watts
    • 0.0375 Amps (37.5 milliamps = 37.5mA) @ 240V = 9 Watts
  • Dimensions: 
    • Mono Tube DI: 1.75" x 13.5" x 4"
    • Stereo Tube DI: 1.75" x 19" x 10" (Occupies 1U)
  • Unit Weight: 
    • Mono Tube DI: 3 lbs.
    • Stereo Tube DI: 6 lbs.

Specifications subject to change because they just might.



Older black-faced version produced in the mid-1990's. 
Photo courtesy of Dr. Frankencopter. 

Oldest black-faced version produced at old VTL factory ca. 1990-1993. 
Photo courtesy of Ed Tuton collection. 

The gutz of the older ones look like this: 
This guy needs to find the bolt for the power tranny and screw it back in...