Mac audio output specs

[MagnumOP]

Does anyone know what the output specs are of the audio jack on a Mac? I have poked around the interwebs but without any luck.

I'm looking for this kind of information:
Impedance
Power Output (RMS)
THD
Frequency Response
Signal to Noise

 

[ChrisA]

Does anyone know what the output specs are of the audio jack on a Mac? I have poked around the interwebs but without any luck.

I'm looking for this kind of information:
Impedance
Power Output (RMS)
THD
Frequency Response
Signal to Noise

I think it depends a lot on which Mac you have. Except for THD, it would certainly be easy enough to measure if you had even just simple test gear like an AC voltmeter function of your DMM.

The biggest problem with the Mac's built-in audio is the lack of an analog gain adjustment. The digital sliders effect the dynamic range so you have to leave them at 100%

Measuring THD requires a system that has about 10x lower THD then the system being measured. It is not easy to find test gear sensitive enough. I have however used the Mac to measure some tube based audio gear.

The thing to watch for is just plain old digital hash leaking into the audio. If you are really concerned get an external USB audio interface for about $150. These do come with specs.