If you could have one super-power that could improve your angling, what would it be? How about some crazy Aquaman communication thing whereby you could just speak directly with the fish? That might be helpful in catching, but since folks don’t seem to have such a skill, perhaps underwater vision would be a useful super-power? If you could see where they live, they would be easier to catch, right? Well, guess what – you can have that power! Yep, underwater vision or at least a digital version thereof, is available to anglers everywhere. All you need is a way to float yourself and the desire to learn a couple of basic concepts.
Obviously, most of you have figured out I’m referencing sonar, not super-human powers. For those that were holding out for the comic hero stuff, well, read on ‘cause I’m going to make this article so simple that even you can apply it to your fishing.
First, some background info: Sonar is an acronym for “Sound Navigation And Ranging” but since the 70’s, the commonality of sonar in so many uses has brought the concept mainstream. Just about any well-equipped modern boat has some version of the technology and many boats feature GPS – an acronym for “Global Positioning System” – with sonar in the same unit. I don’t know how you fish, but sound navigation and ranging and global positioning systems sounds pretty much like fisherman super-powers to me.
While all this technology can seem overwhelming, the truth is it is very accessible to a wide range of boaters, from kayakers to full-on bass and walleye derby rigs. You can spend around a hundred bucks or several thousand depending on your goals. The key is looking closely at the various features each brand and model provides and determining if they are right for your application and budget. For the sake of this article, I’ll break down the major features you should consider first and then look at some specific units based on three price points – you can decide what is appropriate from there. For the record, my entire fishing career has seen my boats equipped with Lowrance electronics and for this reason, I’ll speak primarily from personal experience with these units. The various brands all feature different menus, user interfaces and network technology, but the sonar and GPS concepts are about the same, regardless of the brand.
Fundamentally, all of the brands and models have basic sonar, meaning a 2D image depicted in either color or black and white (aka grey scale) that scrolls across the screen. What the sound wave is detecting is changes in density and the various densities are depicted in either grey scale (varying degrees of grays/blacks, with darker equaling denser) or different colors. Color is easier for beginners to understand and typically easier to read in sunny conditions, but with a little practice grey scale can be learned and will save a few bucks.
Screen size can have as much to do with being able to identify what you’re looking at as anything else; size and pixel count will determine the amount of detail communicated. For instance, if you have a small screen that is only 100 pixels tall and you’re looking at water 100 feet deep, each pixel equals one foot, not ideal for details like fish near the bottom regardless of color/grey scale image. More pixels and larger screens equate to more detail, more cost and overall unit size.
Traditional sonar provides a view of what is directly under the transducer (the physical part that sends and receives sound waves, typically mounted either on the transom, electric trolling motor head or inside the hull on some fiberglass boats) and always a little behind the boat depending on speed. It gives you a continuously scrolling record of what you just passed over. The screen may be stopped to study something that catches your eye, but otherwise the info keeps flowing by.
Even with all the new 3D imaging available these days, my Lowrance units are typically set to display traditional sonar screens, albeit backed up with 3D imaging, which Lowrance calls DownScan. Traditional sonar is excellent for subtle variances in density (like fish right on the bottom), deep water applications and overall simplifies the view. Lowrance and other brands all offer a wide range of traditional sonar units and they are the most affordable style you can buy. Adding 3D capability is getting less expensive as the technology matures and it’s a good addition if it’s in your budget.
Lowrance calls their imaging application StructureScan; I’ve utilized it on all my boats since its inception. These days you can get a unit that has only sonar and DownScan or you can step up and get the full package that includes side scanning capability. To put it simply, traditional sonar will show you that some sort of hard object is on the bottom; DownScan will show you that it is a cinder block lying on its side. Sonar will show you clutter with fish around it; DownScan will show you it’s a willow tree with fish suspended in and around it. Basically, with even speed and a straight pass over something, you’ll get a nearly photographic view of it. As part of the StructureScan package, side scanning will show you the same type of detail, but way out to either or both sides of your boat. This allows an angler to effectively look at large swathes of the lake bottom while looking for both structural elements and fish-holding cover. The 3D effect is accomplished with shading and a harder return is depicted with lighter color while a soft return is seen as darker, meaning it’s either physically softer or farther away from the transducer.
When it comes to looking specifically for fish, especially those tight to the bottom, traditional sonar really shines for me. But for dissecting structure (the actual contour of the lake bottom, drop-offs, channels, etc) and cover (anything sticking up or out from the lake bottom, wood cover, weed lines, rocks, etc) StructureScan and similar technologies are the way to go. The detail is amazing and the ability to look well out to the sides – 350+ feet out to each side in some units – is invaluable for saving time. Flatter bottom contours is where the SideScan works the best; on really steep banks/areas some information is lost.
If you really want to get into some serious electronics discussions, terms like transducer frequency will come up. Very generally speaking, increased frequency (measured in kHz) yields increased image detail, but less range. Manufactures now offer units with multiple frequency transducers; these are the best of all worlds as they allow excellent detail, target separation and shallow-to-deep water effectiveness. Since 3D imaging and traditional sonar use similar technology, the principle applies to both. Also generally speaking, the more total power the sonar unit has, the stronger the signal it will send (called ping) and bounce it will receive (called echo). This plays into the multi-frequency vs. single frequency transducer debate to some degree, but as I already mentioned, multi frequencies yield better target separation and less possibility for interference while single frequency transducers (commonly referred to as broadband sounders) yield the clearest bottom track and great marking of suspended fish/bait, but are more susceptible to ambient underwater noise interference. When you get into higher end 3D technology, really high frequencies yield great detail at closer ranges.
All that sonar and imaging technology is awesome for finding fishin’ holes, but you know what is more awesome? Being able to get back to those holes effortlessly or being able to sit a cast length away and know you’re hitting the key spot or being able to easily share those holes with your friends. You know what makes all that possible? GPS! Who knew that the United States Air Force could help you catch fish?!
GPS is not new at this point; in fact it’s been in civilian use since the mid 90’s. The Air Force may administer the technology, but just about everyone in American has access to it through our smartphones or otherwise. As an angler, combining GPS with sonar in a single unit or on a network is the cat’s meow for fish catching technology. Folks often ask about just buying a sonar unit and utilizing their phone or hand-help GPS for marking spots and you can certainly do that, but having the two different info streams on one cohesive unit allows for instantaneous use and layering of data. See a rock pile you’d like to come back to on your sonar? No problem, just scroll the screen back to it, mark a waypoint, and viola – you can then turn the boat around and go to the exact rock pile you originally saw on the sonar 200 yards back.
GPS allows you to follow a specific trolling pattern, grid out a flat while scanning it, plot a trail following a creek channel and perhaps most importantly, gives you scalable maps of the lake you’re fishing. In the case of many popular lakes, you can get map “chips” (SD cards pre-loaded with hyper-detailed maps, including contour intervals of one foot) that take a ton of guesswork out of finding likely spots to fish.
My GPS data is some of my most protected info. It depicts many years’ worth of waypoints and critical trails, even of lakes that I rarely fish. I may not have been there in several years, but the waypoints I have accumulated will give me a starting spot. With most GPS-equipped sonar units you can insert the SD card, download the data to the card and then physically transfer the data for back-up or sharing purposes. Built-in GPS is, at least in my mind, almost mandatory if you’re considering new electronics for any application. It just isn’t that expensive in the grand scheme of things to miss out on the advantages it offers the angler.
Alright, enough info about various features, so let’s look at a few good choices to consider. For those either on a tight budget or fishing from a simple hand-launch craft like a kayak or jon boat, spending $300 or less still yields viable and effective options, so let’s start there.
My personal hand-launch boat, a mid-90’s spec Coleman Crawdad, is equipped with a Lowrance Mark-4 sonar/GPS unit. I chose it because of my aforementioned statement about the usefulness of GPS in any situation. I didn’t want to spend too much money on a plastic boat, but I wanted to have both sonar and GPS combined in a physically small unit. I saved money by not considering 3D imaging or a color screen. While that relegated me to what some may call “old school”, the truth is I can determine depth, temp, bottom density and shape and fish, all while utilizing GPS to “memorize” and return to spots. This unit is about $200. If you’d rather DownScan imaging in lieu of GPS, while staying in the same price range, a Mark-5X DSI (about $200) will give you the DownScan ability and a slightly larger screen. If you want color and DownScan, plus variable frequency sonar, an Elite-4X CHIRP (also about $200) is a good choice, though you’ll lack GPS. If you can swing about $300, the Elite-4 CHIRP unit will give all the bells and whistles in a small, easy to install/use and affordable package. Incidentally, any of these units will operate on a tiny little 12V battery, definitely a plus for simple hand-launch boats.
Let’s say you’re more in the market for a mid-size unit with larger screen size, full color and more robust processing. Perhaps it’s for an upgrade on an older boat or a new but somewhat basic aluminum boat and you can spend up to $1000. In this price range, a diagonal screen size of 5”-7” is suggested and I’d say that GPS should be a mandatory consideration. The Elite-5 HDI would be a good starting point as it has GPS, color sonar and DownScan, all for about $700. For a hundred more bucks, you can get the Elite-7HDI; the same basic features as above, but with a larger 7” screen. This, to me, is Lowrance’s best overall value in this price range. At the top of the range in terms of price and features is the HDS-7 Gen2 Touch, a serious player for any boat. In addition to the features the other units have, this unit features full StructureScan – meaning you can look out to the sides of the boat with 3D imaging – as well as a touch screen user interface. We already talked benefits of side scanning and the touch screen is sweet for speed and simplicity. It’ll cost you nearly a grand, but it will do anything most users could possibly ask for.
My 21’ Ranger bass boat is my main office. I spend a lot of time in it and much of that time is spent utilizing the electronics system. If you’re perhaps a weekend tournament guy or a hardcore angler with a full size boat and applicable budget, then current high-end units will amaze you. I’ll take the price limit out of the equation for this discussion, but we’ll keep it in mind for value purposes. My boat is equipped with twin HDS-9 Gen 3 Touch units, one at the helm and one on the bow, which are linked together via a network. The Gen 3 adds CHIRP (multi frequency, as we discussed) sonar and a few other tech bits and the 9” is obviously a larger screen. Full StructureScan, HD screen, touch and/or button controls and a host of other features are built-in. For fresh water applications the only way to get more out of an electronics unit is to add a larger screen and that can be arranged up to 12”! Products in this price range ($1500 and up, let’s say) get you features too numerous and detailed for this article, but also units that will amaze you. At $1500ish, the HDS-7 Gen 3 Touch StructureScan bundle is a great value in a full feature unit, while the nine and twelve inch versions add screen size for visibility, especially when the units’ displays are split-screened (a feature all of the units I’ve mentioned have) to display various data streams.
It is important to reiterate that this article is written from personal experience with Lowrance; other brands offer their versions of the various features I’ve mentioned. Spend a little time comparing them all at www.SportsmansWarehouse.com to learn more for yourself.
I’ll end with this: I asked a bunch of full time touring bass pro’s what they thought was the single biggest asset they had in their boats. Without variance, this unique profession of guys who seem to have almost super-human ability to find and catch fish under any conditions, on any lake, at any time of year answered the same way – their electronics. The use of sonar and GPS quickly solves the fish-finding puzzle for them on the largest and most pressured waters in the country. Regardless of your price range or boat size, I promise you that some carefully considered time and money spent on electronics will help you catch more fish, too!