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You are here: MacNN Forums > Hardware - Troubleshooting and Discussion > Consumer Hardware & Components > SoundSticks + Power Mac G5 = buzz

SoundSticks + Power Mac G5 = buzz
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angelmb
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Dec 8, 2014, 12:38 PM
 
So I have this particular issue where if I attach the SoundSticks III to the audio line-out port of the Power Mac G5 (Late 2005 model) there is a very annoying buzz coming out from the satellite speakers.

I have tried to rule out ground issues by connecting the SoundSticks power cord to different outlets, UPS devices… but that didn't solve the nuisance.

Related info:
- If I attach the SoundSticks to a Mac mini (2011 model), which is sitting side by side to the Power Mac G5, there is no buzz.
- If I attach another set of speakers, (Scandyna MicroPod) to the Power Mac G5 (audio line-out port) there is no buzz.

I have uploaded an audio recording of what the buzz sounds like. Actually, it’s way louder that than, though.

Any advice is much appreciated.
     
Mike Wuerthele
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Dec 8, 2014, 02:44 PM
 
Has this always been the case?

Compare the line-out plug on the different speakers to the Soundsticks. Anything different?
     
P
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Dec 8, 2014, 05:28 PM
 
That seems like a ground loop, as you've already suspected. Is there anything else connected to the MP that might be on a different ground? Do any other speakers have a similar noise? I remember my iSub being extremely sensitive to things like this.

(I know it doesn't help, but personally I've given up on trying to figure out silliness like this - I use speakers with an optical connection exclusively these days)
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
reader50
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Dec 8, 2014, 05:45 PM
 
That plug may not be going in all the way on the G5 port. Try inserting a 1/8" extension cable between computer and speakers.
     
angelmb  (op)
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Dec 9, 2014, 09:38 AM
 
Originally Posted by Mike Wuerthele View Post
Has this always been the case?
Actually, these SoundSticks III have always been attached to the Mac mini where they work perfectly. The Power Mac G5 has never had any other speakers besides the Scandyna MicroPods.

As a distant reference, I had the original SoundSticks working flawlessly with a Yosemite G3, but that was something like 14 years ago when they were firstly released.

Now, I have this very vague recall where I think I had read somewhere, online Apple Store maybe, about some weird issue regarding the SoundSticks III and ‘obsolete’ Macs like the Power Mac G5, but then I fail to see how that might have the case with something that requires no dedicated hardware or software whatsoever.

Maybe my long-term memory is playing tricks on me. :-/

Compare the line-out plug on the different speakers to the Soundsticks. Anything different?
Well, the SoundSticks’ is a bit more stylish… and I am being a bit superficial here because I can’t see what’s going on inside those.

Do these (low quality) pictures help.?

black plug: SoundSticks III


white plug: Scandyna MicroPods
     
angelmb  (op)
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Dec 9, 2014, 09:46 AM
 
Is there anything else connected to the MP that might be on a different ground?
There are a bunch of things connected to the G5, some are on the same UPS, some to other UPS (same APC model, but this one I think doesn’t work properly, so I use it for the little stuff that don’t really need a functional back-up system), but then, if I plug the SoundSticks to the working APC UPS, the same that powers the G5, nothing changes and the buzz keeps coming out.

Should I de-attach everything but the SoundSticks from the G5 and the APC UPS and see if that helps.?

I remember my iSub being extremely sensitive to things like this.
Ironically, the issue here is just with the satellite speakers, the iSub is as quiet as a mouse.

I use speakers with an optical connection exclusively these days
What are the advantages of those over the stereo minijack.? I am not audiophile, so please, keep it simple.
     
P
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Dec 10, 2014, 10:23 AM
 
Originally Posted by angelmb View Post
Should I de-attach everything but the SoundSticks from the G5 and the APC UPS and see if that helps.?
Yes, that would be useful as a troubleshooting exercise.

Originally Posted by angelmb View Post
What are the advantages of those over the stereo minijack.? I am not audiophile, so please, keep it simple.
I'm no audiophile either - I've just decided that I don't have time to spend on troubleshooting things, and I'd rather enjoy good audio than work to make it slightly better.

The reason the optical cable works to eliminate ground loops is because there is no conducting medium between them. Plastic isolation over a glass fiber, neither of which conducts electricity, means no ground loops.

An optical cable works by sending the digital audio stream - by default CD Audio, 16-bit 44.1 kHz, effectively a WAVE file - to the speaker to decode and amplify. This means that the audio circuitry in the computer is completely irrelevant, so the sound will be as good as the speaker you buy. I find that this simplifies things immensely, as long as stereo sound is enough. If you want 5.1, it gets trickier, but let's not go there now. I currently use these speakers, and I am very happy with them:

http://www.amazon.com/Audyssey-Lower.../dp/B005FLG3OQ

Unfortunately they have been discontinued by the manufacturer. If I had known, I'd have bought 10.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
angelmb  (op)
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Dec 12, 2014, 08:25 AM
 
Originally Posted by reader50 View Post
That plug may not be going in all the way on the G5 port. Try inserting a 1/8" extension cable between computer and speakers.
Apologies for the lack of reply. I am still looking for that extension cable I should have lying somewhere here… along with several tens of wires.
     
angelmb  (op)
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Dec 14, 2014, 02:55 AM
 
Well, I finally found the extension cable, but alas it didn’t help a bit and the buzz keeps coming out if the SoundSticks are attached to the Power Mac G5.

I would have uploaded a picture of it, but dropbox’s been down, at least for me, since yesterday.
     
Mike Wuerthele
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Dec 14, 2014, 01:19 PM
 
The Soundsticks thing you're remembering is from the USB version of them.
     
angelmb  (op)
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Dec 14, 2014, 03:37 PM
 
Thanks for pointing that out.
     
angelmb  (op)
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Dec 16, 2014, 02:10 AM
 
So, dropbox is working again on my end, and thus I’ve uploaded the picture of the extension cable, here is it.

     
jmiddel
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Dec 20, 2014, 02:54 PM
 
     
Spheric Harlot
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Dec 20, 2014, 03:49 PM
 
     
angelmb  (op)
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Dec 22, 2014, 12:36 PM
 
Originally Posted by Spheric Harlot View Post
Early versions of dual processor G5 computers have noise problems. The first one is ground loop-based interference, which sometimes causes noise leaks into the analog audio outputs. This bug was fixed in Rev. B G5.

Thanks S.H. The G5 2.3 GHz dual-core, being the last revision of Power Mac G5 ever built, should be free of that issue; shouldn’t it.?

I will look at that device jmiddel pointed out to us.

If only Scandyna subwoofers were not that expensive to being with.
     
   
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