BTE Audio - TS' Secret v0.6.0.1 (free)

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Tube Screamer®’s Secret

This work is dedicated to Mr. S. Tamura, the designer1 of the Tube Screamer®

TUBE SCREAMER® is a registered trademark of Hoshino Gakki Co. Ltd. It is used solely to identify the product whose tones and sounds were studied during the research and discovery of the information provided in this article. This information is provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose. The author specifically disclaims responsibility for any loss of profit or any consequential, incidental, or other damages resulting from the use or misuse of the information provided in this article. VST is a trademark of Steinberg Media Technologies GmbH.

Although the circuit design details of the legendary Tube Screamer® overdrive pedal have been extensively analyzed and documented2 in the past, the key aspect of its design, which is primarily responsible for the signature overdrive sound, has remained unrevealed. This key aspect consists of a subtlety in the clipping circuit employed by the legend.

Operational Amplifier based inverting amplifiers with back-to-back diodes in the negative feedback path are common clipping circuits which are regularly utilized in overdrive and distortion effect designs3. Read more here.