Headphone vs line level outputs from computer, etc.

**timeshifter** · 12-31-2006, 03:35 AM

I’m considering wiring the sound for my Intel-based Mac Mini carputer as illustrated in this thread and in this picture:

A couple of questions:

1) I’m confused about headphone vs line outputs. Apple calls the port on that machine a headphone port. It doesn’t seem like that is the same as a line level port. I thought a line level output was always at the same voltage that didn’t fluctuate. But, don’t most amps expect line level inputs?

2) How is the volume controlled? The computer does this and you control it through software, right? If that’s the case then I guess it never really is true line level output on any of the systems people are discussing on the board.

3) Does the Griffin iMic solve any of these problems for the Intel-based Mac Mini?

4) What about digital optical out. Is there any INEXPENSIVE way to use this. All the 5.1 amps I’ve seen with the digital optical input are at least $400!

(PS - I've already

and

till my eyes are red)

**spoonraker** · 12-31-2006, 08:11 AM

1) I was under the impression that a line level signal simply referred to the signal before it was processed by the amp, and not necessarily a specific voltage or whatever you're getting at...

2) Yes the volume is controlled through the PC. If you have a remote knob for your amp, you can use it as well, but that would be kind of pointless.

3) What problems? So far the only question you've asked is whether or not the computer controls the volume, which is does.

4) I have no idea, keep shopping around, my guess is no.

It seems to me like you just don't trust plugging your headphone port into your amp because....well I don't know why. It works just fine, pretty much every single user on these forums does it who doesn't use AUX input, I did it myself for a while before I switched to 5.1. The amp has no problem accepting input from the soundcard's headphone output. Just make sure you set your speaker settings to 2.1 if you're going to wire it that way.

Also I don't know what kind of soundcard you'll be running, but if possible use 5.1, it sounds tons better and isn't any harder to wire.

**timeshifter** · 12-31-2006, 10:51 AM

Originally Posted by spoonraker

It seems to me like you just don't trust plugging your headphone port into your amp because....well I don't know why.

The reason I don't quite trust is because of my experience with using an iPod in my car. I had a CD changer adapter on my stock head unit for my iPod. At first I had a cable that converted from 1/8 in plug on the headphone jack at the top of the iPod to RCAs that went into the adapter. Sound level was controllable by both the iPod and by the head unit. Later I bought a cable that went from the iPod's dock connector to the RCAs - which put out a line level signal. Sound level was only controllable by the head unit now. The latter setup sounded much better and louder and clearer.

That's why I don't trust it. Maybe it's different with a computer output. A quick search of ' "sound card" green blue pink ' lands me on a Wikipedia page that explains that the green output standard is a line out that can also be used for headphones.

Originally Posted by spoonraker

I don't know what kind of soundcard you'll be running, but if possible use 5.1, it sounds tons better and isn't any harder to wire.

I'll be using the sound card built in to the newer Intel-based Mac Mini's. Here's a pic:

I guess the difference between it and other sound cards that people are using is that the 5.1 on the Mac Mini is digital only. To use the digital 5.1 you need a special tip that reaches deeper than the 1/8" analog plug.

I suppose that when you say use it as 5.1 you're thinking of a sound card that has all the 5.1 channels output as analog? Is there a simple inexpensive way to convert the 5.1 digital to analog? Or, as I questioned above is the ONLY way to use 5.1 with a $400+ amp?

**spoonraker** · 12-31-2006, 01:21 PM

I guess I understand your apprehension after your experience, but I can tell you from mine and hundreds of other people's experiences that the headphone port is a perfectly usable line level signal.

Also, I see now why you can't use 5.1, because you don't have 5.1 unless you use digital, which would require an expensive amp. That's too bad, but 2.1 isn't really all that bad, except I found that the signal sent to my subwoofer sounded like crap, but the regular speakers sounded good and clear.