It does depend on whether more than one unit will be operating a transducer at the same time, what the operating frequency (or frequencies) will be, and what the beam width is, but don’t forget the shape of the sonar beam and whether it comes out of the bottom or sides of the transducer. The depth of the water and the composition of the bottom will also affect whether you will see any sonar-to-sonar interference or not.

What unit and transducers are you talking about here?