they sound very very similar. closer than most would probably admit, but the zoom has more upper treble. probably above 9k so it sounds a little more "crisp". The tascam seems more full bodied. Probably more below 200hz. And the metallic ringing seems more noticeable on the tascam, so that could be more mid treble response as well. But i'm guessing on graph they'd be pretty close. And there could be some other factors as well. Frankly, both sound very good. The treble could be eq'd on the tascam as could the lows on the zoom to probably make them even more similar. but on their own i doubt anyone would feel they sounded very different. They're also surprisingly close for how different they are too. The zoom has a very cool compact design and i prefer those lcd screens myself. The tascam is larger, but you can swap the mics with better mics if you want...