Beyond Power
Sounder-power issues change when the topic turns to Broadband and CHIRP units.
Lowrance/Simrad’s BSM-1 Broadband module generally uses about 200 watts of power and has recorded depths to 5,000 feet, Edmunds says. “It changed the way a traditional sonar works. Instead of focusing power into the water, it’s filtering and looking at the smallest signal returns.”
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| (1) Garmin’s GPSMAP 546s multifunction display pairs with (2) a 600-watt transducer. Garmin’s GSD 26 CHIRP sounder module (3) pairs with a transducer (4) that generally measures more than a foot long. Above right: Simrad BSM-1 broadband sounder module (transducer not shown.) |
In order of price and performance, Edmunds says, a sounder lineup would go something like this: 600-watt, 1 kW, BSM-1, 2 kW, 3 kW, CHIRP.
Garmin, Lowrance/Simrad and Raymarine all market recreational CHIRP sounders. Furuno currently sells commercial-grade CHIRP gear.
Kiburz says Garmin’s GSD26 CHIRP unit uses anywhere from 300 to 3,000 watts. CHIRP, which sweeps through a broad range of signal frequencies, can operate at lower power and still achieve depths — up to 10,000 feet in some cases.
In the end, for most anglers, choosing a fish finder and transducer comes down to price plus vessel and fishing style. Competitive captains often find that the higher-priced fish finders pay off at the scales. On the other hand, you’ll never catch me saying weekend anglers aren’t competitive.








