Computer and stereo question???

[Benny Profane]

I'm going to use and old G3 IBook as a "juke box" hooked into my stereo, since it seems to be good for nothing else these days, but I'm getting a nasty hum after I hook the Y cable into the stereo. I'm coming out of the headphone jack into the receiver with a monster cable split Y cable. I have 5 other devices hooked into the stereo, with no problem.

[Free Range Lobster]

Its probably the laptop itself creating noise.
Turn off the laptop with it hooked up and see if it goes away.

[mntlion]

if the computer works why not sell it and use an ipod?

less background noise from that I would think.

[advres]

I used to do that with an old tower. The 1/8" minijacks suck for that. I ended up getting a different soundcard with RCAs out and the hum was no more.

[bossass]

If you have airport in that computer, you could get an airport express base station and just use the audio out to stereo function on it, "airtunes". Works really well. Airport Ex. just got a price drop and you may find used or refurbs even cheaper.

[spindrift]

Grounding problem? Try googling "grounding hum" or "ground loop"

I've found the audio out of PBs to be pretty noise free.

[OldSchool1080s]

If you are running power cables across or near the audio cables you may produce a hum. When I installed my sub i ran the RCAs down the left side of the car to the amp and the 4-guage power cable along the right side, that way they never cross and no hum...i think this is similar to the grounding idea

[SuperChief]

try a different cable then try it on a different stereo to isolate the problem

[AsheanMT]

Make sure the cables are plugged in all the way so that they ground properly and make sure there are no power cables near/touching your RCA's.

[Snow Dog]

It sounds (sic) like a ground loop. First unplug the laptop power and run off the battery. If the hum goes away then there's your problem. Fixing it can be a hassle. First, plug the laptop into the same powerbar as the stereo and make sure that the wide blade (on the plug) is in the wide slot (on the outlet). If both blades are the same then flip one or both (mac and stereo). If they are 3-prong plugs then disregard this fix and search for "grounds loop stereo mac".

[dirtybryan]

Snow Dog hit it on the head and saved me some typing.

Also it could be due to "noise" in your power lines if you find this to be a problem whenever the stereo is playing.

[Benny Profane]

Hey, thanx, geex.

Seems to be associated with the Cable (tv) and the power supply to the external hard drive I have firewired to the IBook. when I disconnect either, the hum goes away. I'm playing it right now with the cable unplugged from the digital box, and the external drive powered up (that's where all the music is) and it's fine. But I can't live like that. And the cable box power isn't the problem - it muct be some alien ungrounded signal coming through the Cable itself. oy.

[Snow Dog]

You can buy an isolation transformer for the drive power supply. As the name says, it electrically isolates the equipment (power supply) from the outlet. You just need to know the amp or watts of the drive (and laptop just to be safe).

edit: car audio shops use an audio line isolation thingy to deal with ground loops. That might be easier to find than a 120V isolation transformer.

[spindrift]

If the issue is the cable itself (which it sounds like it is), there are an assortment of splitters/filters/isolation devices that you can use. Google for "cable tv ground isolator" for places to look. Similar searches will also yield interesting results. Make sure that any splitters/filters you use pass both cable and internet frequencies if you want both past the filter. Been a few years since I dealt with these, so that's about all I remember...

Not sure this is the product you want - but the discussion is in decently layman's terms. Lots of cables have weird ground things going on - even down to what your neighbor is doing (or not doing in terms of termination)...

[Squatch]

tangent: when I power down my powerbook, and my printer is hooked up, I get a weird mexican radio station for a brief moment. a friend has the same printer, cable, and laptop, but he gets the BBC (or some other british thing).

no joke.

[mrkristofo]

If you have airport in that computer, you could get an airport express base station and just use the audio out to stereo function on it, "airtunes". Works really well. Airport Ex. just got a price drop and you may find used or refurbs even cheaper.

ding ding ding.