The Tascam DR-05 (also 05x, 07mkii, 07x) has no switchable “line-in” mode. The external input record level is set over a continuous range from mic level to a supposed “line level”. Unfortunately, even with the gain set at minimum, the sensitivity is too high for standard consumer line level and hot condenser mic signals (not to even mention +4dbm professional output levels). The full scale sensitivity at minimum gain is 500mv (0.5v) RMS. Anything hotter than that will clip the A/D converter. I have used an in-line attenuator (with a battery box for mics) to make it work, but ultimately moved on to a recorder with more useable level ranges.