337

About the 337

The Darkvoice 337 is a high-end Output Transformer-Less (OTL) tube headphone amplifier that uses two pentode tubes (6J8P) to amplify the left and right channels respectively, and two triode tubes (6N5P) with low internal resistance as cathode outputs for each channel. It features a dual mono design with separate power supplies for each channel, providing clean, low-distortion amplification. The amp supports headphones with impedance ranging from 32 to 600 Ohms, delivers output power greater than 2W, and has a frequency response of 10Hz to 35kHz (-1dB). It achieves a signal-to-noise ratio greater than 100dB, ensuring a quiet background. The amplifier is known for its tight bass, clean midrange, and dynamic sound, making it suitable for demanding headphones like the Beyerdynamic DT880 600 Ohm. The unit is robustly built with separate volume controls and power switches for each channel, and it runs hot due to tube operation, requiring proper ventilation. Tube rolling is possible, allowing users to customize the sound signature. The amp operates on 220V/50Hz power supply and measures approximately 280mm (length) x 418mm (width) x 200mm (height).