The Azden product line contains a full spectrum of on camera UHF mic systems. The biggest technological difference between these and the less expensive VHF systems is in the way various radio signals travel. VHF signals tend to travel in a straight line, and when they encounter obstacles like chairs and tables, and even people, they bounce , or reflect, off these objects. The result can be noise (hissing sound), or drop out. The drop out is caused by the original signal and the reflected signal in effect canceling each other out for an instant. Either of these factors can adversely affect your soundtrack. On the other hand, UHF signals tend to travel either through or around these same objects, so there are no reflections, and noise and dropouts are virtually eliminated. This is the biggest advantage that UHF has over VHF. Add this to the to the fact that these systems come with 188 field adjustable channels, and the potential for interference is virtually eliminated.