throwable

I recently had occasion to attach an external microphone to my Mac. I plugged it in, went under “Sound” in System Preferences, and chose “Line In” as the sound input device. Then I said a couple of words to check the input level. Nothing. I tried increasing the input volume. Still nothing. I shouted. It barely registered. I thought perhaps the battery in the external mic was low, so I replaced it with a new one. Didn’t help.

Turns out the “audio in” port on most Macs takes line-level input. The problem is nearly all microphones output mic-level signals, which are weaker than line-level signals. Thus sound from a microphone connected to the analog “audio in” port on a Mac is either too quiet or inaudible.

The solution is to connect the external microphone to a microphone preamplifier and then connect that to the Mac. Unfortunately, microphone preamplifiers can be quite costly. I did find one that was reasonably inexpensive and did the job, though: Griffin’s iMic 2. The iMic 2 has the added advantage that it converts the analog signal to digital outside of the computer, which supposedly helps reduce noise.