What Sonar Frequencies Do Deeper Fish Finders Use?

On this page (7 sections)

1. What is the Deeper sonar frequency range by model?
2. Why do lower and higher frequencies behave differently?
3. Is a Deeper unit dual frequency?
4. Can a lower frequency show fish deeper?
5. Which transducer details should you compare?
6. How should you choose a frequency on the water?
7. Which Deeper sonar frequency range should you use?

Deeper fish finders use different sonar frequencies by model. Some use higher-frequency beams for detail, while others combine them with lower frequencies that cover more water and can work better at depth.

The phrase “Deeper sonar frequency range” does not point to one setting shared by every device. The model matters, and so does the job: finding fish in a broad area calls for a different balance than inspecting a small target near cover.

For the basic terms behind frequency and beam shape, start with Fish Finder Frequency: A Beginner’s Guide. Then compare the frequencies in the specifications of the exact Deeper unit you plan to use.

What is the Deeper sonar frequency range by model?

Deeper's frequency range varies by model, with some units offering three frequencies and others adding a lower option. Common combinations include 90, 290, and 675 kHz, or 100, 240, and 675 kHz.

The Deeper PRO+ 2 uses 100, 240, and 675 kHz, while the CHIRP+ 2 uses 100 kHz CHIRP, 240 kHz CHIRP, and 675 kHz CHIRP. The older PRO+ uses 90, 290, and 675 kHz.

Model generations and regional versions may differ, so verify the current product specifications for your device.

Those numbers describe the sound pulses sent by the transducer. They do not mean that one frequency is always best, or that a unit will reach a particular depth in every lake or sea.

The short version is simple: lower frequency tends to favor depth and coverage, while higher frequency tends to show more detail over a narrower area. For a plain-language definition of the terms, see [What Is Sonar Frequency Range?

The Short Answer](/what-is-sonar-frequency-range/).

Which Deeper sonar frequencies suit each task?

Use the higher setting for detail and the lower setting when you want broader coverage or more depth. A middle setting can balance those aims when your model offers one.

At 675 kHz, a narrower beam can help separate small targets and show detail beneath the boat. It covers less area than a lower-frequency beam, so you may need to pass closer to the feature you want to inspect.

The 240 or 290 kHz option can be a middle ground for general searching. The lowest option, often 90 or 100 kHz, usually favors wider coverage and better signal travel at depth.

Think of these as tradeoffs, not strict rules. Water depth, bottom type, boat movement, and the transducer's design all affect what appears on screen.

Why do lower and higher frequencies behave differently?

Lower frequencies usually travel farther through water, while higher frequencies can show finer detail. That tradeoff comes from how sound spreads and loses energy as it travels.

A lower-frequency beam often spreads wider, giving you a larger area under the boat to search. That wider footprint can make it harder to pinpoint a small object, since echoes from a broader patch of bottom may blend together.

A higher-frequency beam is usually narrower and can return clearer detail from a smaller area. Its signal tends to weaken sooner, so it may be less useful when you need to reach deep water.

The best choice depends on the question you are asking. To find a broad drop-off, more coverage may matter most; to inspect a compact target, a narrower beam may help.

How does beam angle affect the area you see?

Beam angle controls how wide an area the sonar covers at a given depth. A wider beam covers more bottom, while a narrower beam concentrates on a smaller area.

For example, a wide beam can include more fish or structure in a single view, but it may not tell you exactly where each target sits. A narrow beam can help you focus on a small feature, but you may need to move the boat over it.

Frequency and beam angle are related in many transducers, but do not assume every model pairs them in the same way. Check the specifications for both frequency and beam angle before you compare units.

A fish finder frequency chart can help you compare common frequency ranges and their usual tradeoffs. Read it as a starting point, since each transducer's beam pattern affects the view.

Is a Deeper unit dual frequency?

Many Deeper models offer more than one frequency, but the available options depend on the specific model. Multiple frequencies let you choose between detail, coverage, and depth tradeoffs.

A unit with two frequency options is often called dual frequency. Some Deeper models offer three choices, and CHIRP models send a range of frequencies in a pulse rather than relying on a single fixed frequency.

That difference matters when comparing specs. A fish finder with 83 and 200 kHz is not directly equivalent to one with 100, 240, and 675 kHz, even if both offer a lower and higher option.

For a closer look at how multiple settings work, read Dual Frequency Fish Finder: A Quick Guide. Compare the actual frequency numbers and beam angles instead of relying on labels alone.

Can a lower frequency show fish deeper?

A lower frequency can help sonar reach deeper water, but it does not guarantee a particular depth. Actual range depends on the whole sonar system and the conditions in the water.

Frequency is only one part of the picture. Transducer power, installation, water conditions, bottom type, and the target itself can all affect the returning echo.

Depth claims should be read as a maximum stated capability, not a promise that the screen will show useful detail at that depth in every situation. In deeper water, a broad beam may also return less precise location information.

Some traditional transducers list both frequency and a maximum depth. For instance, the Lowrance transducer below supports 83 and 200 kHz, with up to 1,000 ft stated at 83 kHz.

That gives a reference point for those frequencies, but it does not tell you what a Deeper unit will achieve.

Which transducer details should you compare?

Compare frequency, beam angle, mounting style, and compatible fish finder models. Those details determine whether a transducer's range fits your boat and how its readings may differ from a Deeper sonar unit.

Frequency tells you the pulse range, while beam angle helps describe coverage. Mounting and cable length affect where you can place the transducer and whether it suits your boat setup.

Compatibility matters just as much. A transducer can have appealing frequency numbers and still be a poor fit if its connector or model support does not match your fish finder.

The Humminbird XNT 9 20 T is a transom-mount single/dual beam transducer with a 600 ft maximum measuring depth. It is listed as compatible with a range of Humminbird series, with model-specific exceptions.

If your installation uses a trolling motor, the Humminbird AD XTM is a mounting adapter for compatible XNT transducers. It helps mount a transom-style transducer on a trolling motor; it does not add sonar frequencies or change the transducer's depth rating.

For a fixed boat installation, see best through hull transducers to compare a different mounting approach. You can also compare shoot-through-hull transducers for an in-hull installation.

Check the transducer and fish finder manuals for compatibility and mounting instructions.

How should you choose a frequency on the water?

Start with the frequency that suits the task, then adjust if the screen lacks the coverage or detail you need. Use the device's recommended settings as your baseline.

When searching a broad area in deeper water, try the lower frequency available on your model. When you are in shallower water and want to inspect a small feature, try the higher-frequency option.

If the screen looks cluttered, changing frequency may help, but sensitivity can also affect how many echoes appear. Our guide to what sonar sensitivity is on a fish finder explains how that control changes the display.

Keep your speed and route in mind, too. A narrow beam can miss a feature if the boat passes beside it, while a wider beam can include more of the area beneath the boat.

Which Deeper sonar frequency range should you use?

Choose the lowest available frequency for broader coverage or deeper water, and choose the highest available frequency for more detail in a smaller area. Use a middle setting when your model offers one and you need a balance.

Before buying or adjusting settings, identify the exact Deeper model and check its frequency list and beam angles. For a broader look at what sonar can and cannot show, read [Do Fish Finders Really Work?

What to Know](/do-fish-finders-really-work/).

Frequently asked questions

What frequencies do Deeper fish finders use?

Deeper frequencies depend on the model. Some Deeper devices use 90, 290, and 675 kHz, while others use 100, 240, and 675 kHz or add 100 kHz to a 90, 290, and 675 kHz set.

Check the model's current specifications before comparing it with another sonar unit.

Does a higher frequency give more depth?

No. Higher frequencies can show more detail in a narrower area, but they generally lose strength sooner in water.

Lower frequencies usually travel farther and cover a wider area, though the screen can show less fine detail.

Beam shape, power, water conditions, and transducer design also affect results.

Which Deeper frequency should I use in shallow water?

Use the model's high-frequency setting when you want a detailed view in shallow water, such as around vegetation or structure. A lower frequency can help cover more area when you are searching.

Start with the manufacturer's recommended setting, then adjust for depth, target size, and screen clutter.

Are Deeper frequencies the same as traditional fish finder frequencies?

They overlap, but the ranges can differ. Traditional units often offer 50 or 83 kHz for deeper water and 200 kHz for detail, while Deeper models may use frequencies such as 90, 290, and 675 kHz.

Compare the exact frequencies and beam angles for each model before choosing.