Singular Audio Tubedrve Stereo 500 Series Tube Saturator

The Singular Audio Tubedrve is a stereo tube saturator module for the API 500 series (also known as the "lunchbox" format). The Tubedrve utilizes 2 pentode tubes per channel, for a total of 4 tubes per module. The first one is an EF86 and the second one a 6AS6. The 6AS6 tubes is overdriven, providing the distortion.

The 6AS6 can be switched from pentode to triode operation. Triode mode provides a smoother type of overdrive with more ‘even harmonics’. Pentode mode gives an aggressive distortion with more ‘odd harmonics’. Switchable bypass and a mix knob for parallel processing provide pro audio requirements. The two channels are controlled independently from one another.

The module can be controlled with an input or ‘drive’ level, controlling the audio signal going to the tubes. A bias control sets the operating point for the distortion tube, allowing the user to control the bias current. With high and low settings this introduces asymmetrical waveform clipping, providing a more aggressive sound.

A boost switch provides 15 dB of extra gain, for extra overdriven tones. An output level control controls the level coming from the tubes. A simplified overview of how the Tubedrve works can be found in the manual at the bottom of this page.

The front panel is made of black anodized aluminum providing a long and lasting finish.

PARALLEL MIXING

The mix knob provides full dry and wet operation, allowing for parallel processing. This is a great feature to have in a saturator since they tend to compress audio. Parallel processing allows the user to dial in the exact amount of saturation they want and provides full control over dynamics.

A white led lights up when the distortion tube is being overdriven. Furthermore there is a bypass switch which switches the module out using relays for complete bypass.

HIGH VOLTAGE

Plate voltage for the tubes is 240VDC, due to a DC-DC converter which generates the high voltage from the ±16V power supply of the API 500 format. This is needed for the best possible overdrive sound. This is unlike other designs which use the +48V supply for the plate voltage, which leads to a ‘starved plate’ sound. The +240VDC plate supply in this design allows for the best possible tube overdrive sound.

NOS (‘New Old Stock’) tubes are used, meaning they are unused tubes manufactured in the 70s or 80s.