How Transmit Wattage Affects Sonar Readings

Does Transmit Wattage Matter?

Garmin offers many types of transducers. The most basic are rated at 500w and have a single element that resonates alternately at 50 kHz and 200 kHz frequency. Although these transducers are effective and inexpensive, greater performance is achieved with a high-performance transducer. Garmin offers high-performance transducers with multi-element transducers rated for greater power output and usually contain a range of frequencies. 

Higher output power equals a greater depth range, detailed bottom imaging, and robust returns. The actual depths reached with a sounder will vary depending on several factors, including water salinity and sea conditions.

NOTE: Not all Garmin devices are compatible with a high-performance transducer. Check the manual of the Garmin device for compatibility information.

What are Q Values

Multi-element transducers also have lower Q values. Q value is a transducer's quality factor. Q describes the amount of ringing the ceramic element or elements undergo when power is applied to the transducer. The lower the Q value, the less ringing in the transducer, and the better the performance. (The average single-element 500w transducer has a Q of around 25-35, whereas the average multi-element 1kw transducer will have a Q of approximately 6-12.