Dual beam or dual fequency?

[black runner]

Hi I am going to purchase a Garmin 400c that has the option of dual beam or dual frequency transducer. I fish always in less than 100 metres in salt and sometimes in fresh water rivers and lakes.

Am I best to go with 400 watts dual beam 80khz/200khz (45/15 deg angle) transducer or 500 watts dual frequency 50/200 khz (45/10 deg angle) transducer?

I am a bit confused but so far from what I can understand the dual beam (15 deg at 200khz) may be of more benefit for my application. Any help would be greatly appreciated.

Cheers

[black runner]

Hi

Ended up with a Garmin 400C which came standard with a 500 watt dual frequency transducer. Wow! what a difference colour, increased resolution and the nice features like bottom lock, depth line and A/track makes. A big leap forward from the old ff80.

Cheers

[BaitThrower]

Doesnt the 400C have a dual beam/dual frequency transducer? Get the best of both worlds

[black runner]

Well after lots of research and questions the upshot was this.

The dual frequency is exactly what it says - 200khz (standard), and 50 khz frequencies. Both frequencies are independently selectable or can be displayed simultaneously on a split screen. Full functions of the sounder operate with either/both frequencies. Fifty khz is used mainly for deeper water but apparently is also excellent for bottom typing at any depth. The transducer is physically much bigger than the single frequency unit. The dual frequency is higher powered at 500W. A verticle flasher side bar (A-scope) can be turned on and gives a vertical sectional of targets and in the beam.

The dual beam transducer is a switchable (but not both) wide (80khz) or narrow (200khz) beam unit and displays an optional flasher type screen (the circle/wheel type depth display). This is the equivalent of the A-scope above but represented differently

The dual frequency unit performs well in deeper salt water applications over 150m as well as in fresh whereas the dual beam unit would have less punch in the deeper salt environment.

That said, either is good for fresh through to coastal salt work.

I brought the dual frequency as it was the last one in stock. If it had been dual beam I probably would have brought that one.

One thing to be aware of is that the dual frequency transducer can't be mounted on an electric trolling motor whereas the dual beam can.

Cheers