Introduction
The Fulltone OCD (Obsessive Compulsive Drive) is a legendary overdrive pedal designed to deliver rich, dynamic, amp-like tone. Built with a MOSFET clipping circuit and Class-A input stage, it responds naturally to picking intensity and guitar volume changes, producing expressive overdrive that feels warm, open, and highly responsive. It features a High-Peak / Low-Peak toggle switch for versatile voicing, offering enhanced upper-mid presence for an aggressive British-style bite or a smoother, more transparent American-style response. The intuitive 3-knob control layout (Volume, Drive, Tone) allows for fast and precise sound shaping. Designed with a high-quality output buffer and enhanced bypass circuitry, it preserves signal strength and clarity, preventing tone loss or high-frequency degradation. Housed in a rugged metal enclosure, the Fulltone OCD is built for reliability in both live and studio environments, ensuring dependable performance and long-term durability.
Setup
The Fulltone OCD pedal can be powered by a standard 9V battery or a 9V DC power adapter. Ensure the power supply provides at least 43mA of current. To connect the pedal, plug your guitar into the 'INPUT' jack and connect the 'OUTPUT' jack to your amplifier's input. For optimal performance, use high-quality instrument cables.

Image: Fulltone OCD Overdrive Pedal connected in a typical guitar setup.
Operating Instructions
The Fulltone OCD features an intuitive control layout for easy sound shaping.
Controls
- Volume: Controls the overall output level of the pedal.
- Drive: Adjusts the amount of overdrive/gain.
- Tone: Shapes the treble frequencies, allowing for brighter or warmer tones.

Image: Intuitive 3-knob control layout of the Fulltone OCD.
HP / LP Tone Switch
A toggle switch allows you to select between two distinct tonal voicings:
- HP (High-Peak) Mode: Provides enhanced upper-mid presence for a more aggressive, British-style bite.
- LP (Low-Peak) Mode: Delivers a smoother, more transparent American-style response.

Image: HP/LP Tone Modes for versatile voicing.
Gain Switch (Internal)
The pedal features an internal gain switch that acts as a boost. This can be accessed internally or, on some versions, controlled via an external expression pedal. This switch provides additional gain for more saturated tones.
High Cut (Internal)
An internal high-cut switch is available to reduce excessive treble, particularly useful when using higher drive settings or brighter amplifiers. This switch can be adjusted using a small tool like a toothpick or Q-tip.
Expression Pedal Control
The Fulltone OCD includes a jack for an expression pedal, allowing external control over the gain switch. This enables seamless transitions between different gain stages during performance.
Maintenance
To ensure the longevity and optimal performance of your Fulltone OCD pedal, follow these maintenance guidelines:
- Cleaning: Use a soft, dry cloth to clean the pedal's exterior. Avoid abrasive cleaners or solvents.
- Storage: Store the pedal in a dry environment away from extreme temperatures and humidity.
- Battery Replacement: If using a 9V battery, replace it when the indicator LED dims or the sound quality degrades. To replace, unscrew the bottom plate of the pedal.
- Cable Care: Always use high-quality instrument cables and ensure they are not kinked or damaged.
Troubleshooting
If you encounter issues with your Fulltone OCD pedal, consider the following:
- No Sound: Check all cable connections (guitar to input, output to amp). Ensure the power supply is correctly connected and functioning, or replace the 9V battery.
- Weak/Distorted Sound: Verify the power supply is providing sufficient current (at least 43mA). Check the battery level if applicable. Ensure all knobs are set appropriately and not at extreme settings that might cause unwanted artifacts.
- Excessive Treble: Adjust the Tone knob to a warmer setting. If the issue persists, consider engaging the internal High Cut switch.
- Unwanted Noise: Ensure you are using a regulated power supply. Check for faulty cables or interference from other electronic devices.
Specifications
| Feature | Detail |
|---|---|
| Product Dimensions | 5.31 x 3.19 x 2.6 inches |
| Item Weight | 8 ounces |
| Power Requirements | 9 Volts DC (43mA current draw) or 9V battery |
| Circuitry | MOSFET clipping, Class-A input stage |
| Bypass | Buffered & Enhanced Bypass |
| Controls | Volume, Drive, Tone, HP/LP Toggle Switch, Internal Gain Switch, Internal High Cut Switch |
| Construction | Road-ready metal enclosure, Made in USA |
Warranty
Fulltone products are manufactured to high standards. For specific warranty information, please refer to the documentation included with your purchase or visit the official Fulltone website. Keep your proof of purchase for any warranty claims.
Support
For technical assistance, troubleshooting beyond this manual, or service inquiries, please contact Fulltone customer support. Contact details can typically be found on the official Fulltone website or in the product packaging.




