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Lowrance StructureScan HD Review

Lowrance StructureScan HD utilizes an LSS-2 black box coupled to a proprietary transducer to add side and down scanning capabilities to certain Lowrance MFDs.

A single multifunction transducer provides both side and down scanning capability. Up to 500 watts of power can be sent out by this transducer using one of two different frequencies.

lowrance lss-2 structurescan hd black box sounder

Lowrance LSS-2 SturctureScan HD

The LSS-2 module housing measures approximately 8.2-inches by 7.5-inches with a depth of 2.4-inches. The dark grey box and is designed to be mounted on the flat surface of a bulkhead or deck away from sunlight, salt spray, or the chance of physical damage.

Power is supplied to the StructureScan HD black box and transducer via a 12v DC twist-lock cable connection. through the Lowrance LSS-1 black box. Normal power usage is under one amp with inrush amperage of less than five amps.


Once installed and coupled to a Lowrance MFD for data display StructureScan HD is manipulated through an easy to use MFD interface. It can be displayed full screen or in a second window. Up to four windows total can be displayed on large screen HDS Gen2 units while two of those windows are able to display StructureScan HD data on smaller screen HDS units like the HDS-5 Gen2 or HDS-7 Gen2. StructureScan HD is designed to be coupled with a Gen2 MFD.

When a StructureScan HD window is active pressing the menu key will bring up the StructureScan HD menu. Here you can select one of eight color palettes and select display options like surface clarity, noise rejection, flip the left/right view, and turn on range lines.

Lowrance StructureScan Specifications

Transmitter Power (Watts RMS)500
Frequency (kHz)455/800
Transducer Used for TestStructureScan HD
Scanning CapabilitiesSide / Down
Auto Depth RangingYes
Side Scanning Range (feet)300 – Each Side
Down Scanning Range (feet)300
Optimal Scan Speed10 mph
Communication to MFDEthernet – 3
WaterproofSplash Proof
Warranty Period (Years)2

Using the menu system you can also vary the contrast and range as well as select the frequency. The view can be set to display left or right only, both left and right, or down.

There really are no other adjustments to make, gain is set automatically. You can even set the unit to auto range so that is handled for you too. Lowrance has made this system very easy to operate.

At Sea Testing

Florida Keys on the water testing took place with the temporary installation of the Lowrance StructureScan HD system and an HDS-5 Gen2 display on our vintage Seacraft test boat.

lowrance structurescan hd displayed on hds-5 gen2

StructureScan HD and standard sonar data displayed on a Lowrance HDS-5 Gen2. Side scan is on the bottom half of the screen, standard sonar is top left, and down scan top right. Side and down scan picked up the adjacent piling and bottom structure while the standard sonar only picked up the structure. The small mound of bottom structure was located under the boat while the piling stood about 20 feet to the side of the boat centerline.

Two frequencies are available and user selectable. When using the lower frequency, 455 kHz, the system is capable of providing clear sharp side scanned images out as far as 300 feet to the left and to the right as well as down scanned images to a maximum depth of 300 feet.

Switching to the higher frequency of 800 kHz increased the image definition while sacrificing some distance in range. On certain Gen2 units StructureScan data can overlaid on the chart page or saved to a memory card.

To review the system on the water I made a number of passes over submerged rocks and abeam concrete and wooden dock structure. The Lowrance system is very good at displaying a variety of hard structure both under the boat and off to the side.

As you can see in the image above side scan and down scan from the StructureScan HD system showed structure not seen by the narrower beam of the standard sonar.

Final Thoughts

The Lowrance StructureScan HD system provides easy to use side and down scanning capabilities and is a great add-on to any Lowrance HDS Gen2 MFD.

Buy the StructureScan HD system here.