Simrad S5100 Black-Box Fishfinder Module Review

Simrad S5100 Black-Box Fishfinder Module

Traditional fishfinders have been more or less supplanted by CHIRP units, but even CHIRP has its limitations. One of the reasons why is simply size and space; the more you jam-pack into a MFD unit the larger it becomes, and we all want a svelte unit to install at the helm. You can, however, give your fish-finding abilities a shot in the arm by adding a black-box finder which has gobs of power and additional channels. That’s why Simrad has introduced the S5100. Before we dig in and check out the details, let’s take a quick look at the unit in action.

Remember, different CHIRP ranges perform best at different depths because low and high frequency pings travel differently through the water. (There’s a great discussion of how different frequency sonar waves work in the first paragraph under “Myth: Side-Scanners can see a fifth of a mile or more” in the article Peripheral Vision: Side-Scanning Fishfinder Myths Debunked). So having all these channels at your disposal allows you to really focus in on multiple parts of the water column at the same time—even if you want to look at a wreck in 1,000’ of water and the top 50’ of the water column simultaneously.


CHIRP ranges run from 28 to 250 kHz, and you can adjust them as you like. You can also choose transducer coverage that allows for narrow or wide beam-width. Power range runs from 300 watts to a fish-frying three kilowatts. Note that most built-in fishfinders put out 500 or 600 watts, and max out at one kilowatt; you simply can’t get three kilowatts of punch from a helm-mounted unit, because it would have to be two or three times as large.

Another advantage the S5100 get you is extremely effective surface clutter suppression. When we tested the unit the surface remained clear at all times, yet when we went over fish the returns weren’t squelched. Credit continuing advances in processing technology.

Speaking of processing: Simrad’s new NSS evo3 units have more power than ever, and we found CHIRP adjustments as well as screen redraws were blazing-fast. The S5100 is also compatible with evo2 units, NSO evo2 glass-bridge systems, and S2000 fishfinders. Connectivity comes via high-speed Ethernet.