This is the first of Thermionic Culture's Solo series. We chose the Culture Vulture as first to become a mono unit because the original scheme (of Nick Terry's - back in 1996) was to make the Culture Vulture as a guitar distortion unit box, and the prototype is still in use by Edwyn Collins for this purpose, without a service or valve change! The new design is still based around the unusual 6AS6 /5725 distortion valve.
The changes of electronics in the design have been developed by a local young 18 year old electronic whizz-kid, Ricky Sharp. He's also a guitar player and believes in 100% valve electronics, of which his knowledge is rather impressive. As well as adding his own ideas to the audio circuit, Ricky designed the noiseless switching circuit which uses transistors to switch Vactrols. This circuit means still no solid state components in the audio path when switching between "clean" and "dirty" channels. The final design was supervised by Vic Keary, with Jon Bailes, as usual, creating the physical product designs from their concepts and prototypes.
The Solo Vulture must not be thought of as just ½ of a standard Culture Vulture, as it has special extra features, including 2 switchable signal paths controllable either by a toggle switch on the front panel or a foot switch, which makes it suitable for stage use as well as in studios.
The Clean Channel goes straight from the 1st stage to the output stage.
The Dirty Channel is amplified further after stage 1, then it hits the "distortion" valve, before the output valve.
Presence and Active Tuneable Mid Lift as found on the Anniversary editions of the Culture Vulture can be added to the Dirty channel.
There is also a 4 position Low Pass Filter switch to remove unwanted high top.The Presence adds 2 options of broad mid range to the sound.
The Mid Lift is most effective at low current settings (see below) and can be used at all positions of the Distortion Type switch but is most effective with P selected. It's a high "Q" control with 4 active settings tuned musically and, will really emphasise the guitar, bass or other instrument in a mix or, of course, on stage.
The Distortion Type switch affects the way the distortion valve is configured. "T" is Triode(smoothest 2nd harmonics). "P" is Pentode (more aggressive 3rd harmonics), the most popular. SQ1 & SQ2 are the bizarre "squash" settings and should be used for more extreme effects.
The Meter reads the actual current through the 6AS6 type distortion valve. This is controlled by the Bias Control. When the valve current is 0.25 – 0.3 mA it's least distorted. Very low current gives it a thinner more broken up sound. High current and it's a bit fatter and "woolly" 0.1 mA at SQ2 adds an extra octave to the sound (usually).
Inputs and Outputs are ¼"stereo jacks. The Line In on the back is wired "semi floating" so as not to degrade the signal from a DAW. The high impedance DI in on the front, and the Line and low level outputs on the back are unbalanced so the ring on the jack is grounded. Single or 2 core leads can be used when connecting to balanced equipment.
The Solo Vulture could help produce your own individual sound.
Input/Boost 12AX7/ECC83 double triode
Distortion 6AS6/5725 pentode
Output 5725 double triode