hard drive sound in my monitors

[therecordinghouse]

ok, whenever i turn my seagate firewire harddrive on, i get a spin up sound in my monitors. this happens on both my macbook pro, and my p4 pc. sound is the same with both my mbox 2 and my 002r. what the heck is going on?

[albee1952]

How close is the drive to your speakers or signal wires going to the speakers? Are you using balanced cables from the 002r to your monitors?

[The Dougfather]

You may have an earth loop, are both the devices mains powered from the same gang socket, if not try it.

Cheers

[td.Lemmon]

hi there

I have the same problem here. My harddrive is kinda close to the cables, yet all my power comes from one wall socket (if that is what was meant) So is it a ground loop then? I am unsure. Gonna try to move it away from the cables.

(my monitor cables are xlr to jack (digi002) how can i see if they are balanced?)

thanx

[Palli-Moon]

A basic way to find out is to check if the jack is TS (Tips-Sleave) or TRS (Tip-Ring-Sleave). All jacks have atleast ground + the signal but the balanced ones have 2 signal wires and one ground. You can see pretty clearly if the jack has 2 or 3 wires if you just take a good look at it. You can see that all jacks have this black ring on them, but some jacks (like the ones you see on stereo headphones) have 2 black rings. This means that the jack is devided into 3 contact points, and in the case of balanced 2 of them hold the signal and one is ground. But even if your jack is not TRS it's not 100% sure it's balanced, but it's very likely, especially since XLR is normally balanced.

Excuse my english and how bad I am at explaining things but I hope this helped atleast a little bit.

[td.Lemmon]

But even if your jack is not TRS it's not 100% sure it's balanced, but it's very likely, especially since XLR is normally balanced.

So, if i understand correctly:

1. With two black rings it's surely balanced

2. With one black ring it's not balanced (or possibly IS balanced when one side is XLR?)

My monitor cables have only one black ring. I'm gonna open up the XLR side of the cable to check what's happening on the inside.

thanx,

(i hope this information can help the original poster. It is very likely that this is 'my' hum&spin-problem. I'll post the results shortly.)

[Palli-Moon]

no not exactly, if you've got 2 black rings it possibly balanced (and possibly just stereo) but if you've got just 1 black ring it's not balanced for sure. Maybe my talk about the XLR being balanced confused you but the fact is if your XLR is XLR to XLR or XLR to TRS (2 black rings) it's almost surely balanced but if you're cable has got a TS (1 black ring) it can't possibly be balanced.

Oh and one more thing that could make this easier to understand. The difference betwenn balanced and unbalanced cables is really that the balanced ones have 2 wires for the signal wich cancels out some unwanted noise. But the unbalanced ones just have 1 wire (plus ground) wich just holds the signal. XLR also has 2 wires plus ground so it's capable of being balanced but if the other connector just has tip and sleeve, wich makes it only capable of holding the signal and ground, then there's no possibility that it's balanced.

[td.Lemmon]

Here's an update on my former post:

I unscrewed my xlr connector and discovered that it only has two wires (ground and sound).
And, as i understand it now, it has of course, on the jack-end, only tip and sleeve (TS). This has to be my problem then.
Furthermore in the XLR two pins have been linked and the other is ground. So this would be a balanced to unbalenced cable, yes? (With a 6dB signal loss as i found out after some diggin' on the worldwideweb).

Ordered two balanced cables and will see in three days or so if it clears the hummin'.

'I feel I am getting closer to the source'

(thanx Palli-Moon for wiping the clouds from my understanding )

[KingTor]

This problem doesn't sound like a ground (or earth) loop to me, but it does sound like unwanted noise travelling through the chassis ground.

If the balanced cables don't fix the problem by themselves, which depends on how your monitoring system handles noisy ground, then try lifting the SHIELD wire from the XLR connectors--not the ground wire on pin 1, but the one that is connected directly to the metal shell of the XLR connector. (It might be a seperate wire that comes from the actual shielding of the cable which is braided around the other 3 connectors, or it might be a small wire that runs between pin 1 and the shield of the connector.) If there isn't any shield wire or if lifting it doesn't work, then try lifting the ground wire.

[Palli-Moon]

There is still one tiny misunderstanding, you talk about the XLR to TS beeing Balanced to unbalanced, the thing is that it's actually the cable itself that is balanced or unbalanced, not the connectors, so you know, there is no such thing as balanced to unbalanced, just balanced or unbalanced.