Bug Brand Spring Tanker

• Fabricant : Bug Brand
• Modèle : Spring Tanker
• Catégorie : Processeurs de réverbération
• Fiche créée le : 30/04/2015

Spring reverb tank effect with Voltage Controlled elements

An Input Preamp with gain brings the mono signal input up to suitable internal levels before the signal splits to the Output Mixer (Dry) and the Reverb Drive VCA (Voltage Controlled Amplifier). 

This Linear VCA sets the level feeding into the Reverb Core and can be controlled by the Level dial combined with Control Voltage (CV) Modulation from the Polarising Depth control. A Feedback path, again VCA controlled, takes the Reverb output (normalised) and sums it back in to the input of the Reverb Core (do treat this path with care - it can scream!). Of course, an external processor can be inserted within this feedback loop via the Send (Reverb) / Return (Feedback) sockets.

A pair of VCFs (Voltage Controlled Filters), one High Pass (Low Cut) and one Low Pass (High Cut), can be inserted before or after the Spring circuitry with the Pre/Post switch - these give quite different results to the Spring sound. The filters are quite simple 1-pole designs, without resonance, but serve the purpose of shaping the Reverb very well.

Low-noise circuitry is employed to feed and recover the signal through the Spring Tank itself. A diode clipping stage is built into the recovery amplifier to limit any mechanical clangs or feedback above normal level. The tank is a Belton 6" 3-Spring with medium decay time (1.75 to 3.0 sec typical decay) - note there is no provision made to allow swapping of tanks etc. The metal enclosure provides good general EMF screening but do avoid using the Spring Tanker close to extreme sources (power transformers, fluorescent lights, etc.).

The Output Mix combines the Dry and Wet signals and gives impedance balanced mono 1/4" output, while the Wet signal (pre level control) is also buffered for the direct Reverb output (normalised to Feedback).

The four banana CV inputs each feature a Polarising Depth control which allows good control of modulation with variable Attenuation and/or Signal Inversion - they are 'zero' at centre, rising to full (x1) when moving clockwise and fully inverting (x-1) when moving counter-clockwise.