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RAAL-requisite VM-1a Variable Mode Vacuum Tube Ribbon Headphone Amplifier

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RAAL-requisite’s all new standalone ribbon headphone amp the VM-1a features a dedicated variable mode tube circuit design exclusively for driving ribbon headphones. Capable of operating in Ultralinear, Triode or Pentode mode, this top of the line amp delivers uncompromising performance with RAAL's SR-1a ribbon headphones.

A great listen, every listen, with all that you'd expect from RAAL-requisite!

Our Take

This custom built amp features variable mode select for: Ultra-Linear, Triode, and Pentode Operation modes. This direct drive vacuum tube amplifier is compatible with all of RAAL-Requisite’s ribbon headphones. It has selectable SR-1a open-baffle compensation and CA-1a non-compensation for both outputs. It also has a 24-step precision attenuator which is ideal for precise channel matching. On top of that, it has transformer balanced inputs (left/right) and outputs for simultaneous dual headphone operation. Toroidal output transformers and the toroidal power transformer are all magnetically shielded and epoxy cased. Lastly, the amp allows you to select between 115V and 230V voltages, which is great for those who want to use the amp in different regions of the world.


Power Output: 15W

• Bandwidth Frequency Response: 20Hz - 70kHz, -3dB


Power Output: 10W

• Bandwidth Frequency Response: 10Hz - 70kHz, -3dB


Power Output: 20W

• Bandwidth Frequency Response: 30Hz - 50kHz, -3dB


Input Tube: 1x Tung-sol GTB 6SN7 Dual-Triode

Splitter/Driver Tubes: 2x Apex Matched Mullard EL34

Output Power Tubes: 4x Apex Matched Mullard EL34 Quartet

Input Impedance: 50K ohms

Input Sensitivity: 2V

Distortion: < 1%

S/N Ratio: 72dB

Weight: ~29lbs



About RAAL-requisite

RAAL-requisite represents two legendary brands in ultra high-end audio, coming together, to create a sound unlike anything the world has ever heard before.