Units & Measurements Sensitivity

Sensitivity, also called gain, is the setting that controls how much your fish finder amplifies incoming sonar signals before displaying them on screen. It is arguably the most important user-adjustable setting on your fish finder, directly affecting whether you see fish, structure, and bottom detail clearly — or whether the screen is blank or cluttered.

When sensitivity is set too low, the fish finder only displays the strongest returns. The bottom appears thin and faint, fish marks may disappear entirely, and subtle structure goes undetected. When sensitivity is set too high, the display fills with clutter — random noise, suspended particles, interference, and false returns that obscure genuine targets. The optimal setting falls in the middle, showing a well-defined bottom with visible fish marks and structure detail without excessive noise.

A practical approach to dialing in sensitivity is to start with auto mode, then switch to manual for fine-tuning. Increase sensitivity until you start seeing noise and clutter, then back it down until the display shows a clean image with clearly visible targets. The ideal setting changes with depth, water conditions, speed, and the specific sonar mode you are viewing.

Separate sensitivity settings are typically available for different sonar views. Your traditional CHIRP view may need different sensitivity than your down imaging or side imaging modes. Adjusting each view independently gives you the best image quality across all your display panels. Save the settings that work well for your common fishing conditions so you can quickly recall them.