No Sound from External Mic

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Level 1

128 points

No Sound from External Mic

Hi. I'm on Lion 10.7.2 with the Lion Recovery partition deleted (I do an extrea Lion install in a USB external which has the recovery partition). The line in jack for the mic at the back (the built-in mic on top of the Mac near iSight works) doesn't seem to be working (I'm using a normal computer desktop mic, very standard basic computer mic with stand with the normal jack. It's from Creative). I've click in System Preferences-Input- Line In (instead of Internal microphone built-in) and in Audio Midi Setup for the Built-in Input, Built-in Output, Built-in Microphone, its all using 44100 and 2Ch-32bit Float. Do you need to use special microphones if you don't want to use the built-in mic and you wanted instead to use an external mic? Is the iMac (late 2009 i7) mic/line in connector at the back defective (is there a software to test that, like a Apple Hardware Test?)?

Thank you in advance.

Gbu.

iMac i7 Late 2009, Mac OS X (10.7.1)

Posted on Oct 14, 2011 7:47 PM

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Answer 1

Lanny

Level 6

13,183 points

Oct 14, 2011 7:55 PM in response to Alvin777

The audio input jack on a Mac is a line level audio input, not a microphone level input. You need a USB microphone or a microphone pre-amp that would allow the use of an ordinary PC mike with a line level input.

Sensitivity levels for Line Level are around 250 millivolts as opposed to microphone levels that are around 5 millivolts.

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Answer 2

Alvin777 Author

Level 1

128 points

Oct 14, 2011 7:57 PM in response to Lanny

Hi thanks for the reply. I'm glad the Line-in jack is not defective but I wished they would allow normal mic like they would with its headphone jack which can use normal external stereo speakers. What brands and models of mics are compatible with the Line In jack of this iMac that you can recommended (the USB ports are all filled). Thanks again in advance.

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Answer 3

Lanny

Level 6

13,183 points

Oct 14, 2011 8:01 PM in response to Alvin777

Alvin777 wrote:

What brands and models of mics are compatible with the Line In jack of this iMac that you can recommended (the USB ports are all filled). Thanks again in advance.

None that I know of, you would need a microphone preamp.

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Answer 4

Alvin777 Author

Level 1

128 points

Oct 14, 2011 8:09 PM in response to Lanny

I'll research on it, thanks for the heads up (iMac's a great design but I wish Apple just included a pre-amp in the Line-in to make things you already have compatible). Would you know if it still like this in the new iMacs with Thunderbolt (is it a great time to sell this iMac already- any suggestions?)?

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Answer 5

Lanny

Level 6

13,183 points

Oct 14, 2011 8:18 PM in response to Alvin777

Alvin777 wrote:

Would you know if it still like this in the new iMacs with Thunderbolt (is it a great time to sell this iMac already- any suggestions?)?

Yes it is, no changes would be anticipated.

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