Hi Mark, In the sense that all headphones make a noise then the answer would be no there is no difference but there are factors that can and do make a difference but just a correction to prmorgans post, ohms are not one of them! Ohm ratings are one of the urban myths of metal detecting, ohms can be important if we are talking about matching a Bang & Olufsen system to speakers but the tonal range and quality produced by a metal detector is at best, basic and so have little to no effect on the sound that reaches your ears. I can take 12 different makes of speakers all with the same ohm rating and tech spec and they will all sound different and so the speaker tone or "colour of the tone" is the most important when matching headphones to machines.
The Chefphones range uses 16, 32, 64 and 150 ohm speakers in the different models, the tones of which are adapted to certain machines by the shape of the ear cup that they sit in.
So that's the ohms out of the way.
The benefit of metal detecting headphones over normal home stereo headphones is also a curly lead (preferably replaceable) a volume control, a right side cable entry (if you're right handed) and the fact that they will be water resistant and are generally just tougher. I hope that helps