Features MANLEY input & output transformers with nickel laminations in mu-metal cases Flat frequency response from 10Hz-60KHz Mic input PHASE REVERSE switch 2400 Ohm mic input Z; 48V phantom power built-in Hi-Z (100 kOhm) 1/4" DIRECT INPUT Description Product Description The MANLEY all-tube microphone preamplifiers are available in 2-channel or single channel versions, primarily intended for use with modern capacitor (condenser) microphones. Now, 40 to 60 dBs of gain, enough for most ribbon mics, are selectable in precise 5dB steps by varying the amount of overall negative feedback on the GAIN switch. This is a very interesting feature indeed, allowing you to change the slew rate (speed), placement, and tonal balance of the sound from mellow and "tubey-er" through to faster, punchier and more aggressive. See "Notes on Variable Feedback" for more info.