Wharfe's Humming for a while at Start up???

  • Thread starter Thread starter WERNER 1
  • Start date Start date
hum?

i just plugged a computer in my room as my RTA analyzer setup.
Soundcard output went to my stereo preamp/patch bay and then the studio amplifier/ speakers.(passive)

The Measurement mic went into my SIAB, phantom, out of the SIAB to the
soundcard mini plug.

there was a lot of hum going on.

when i unplugged another set of rca stereo cables (totally unrelated to these two pieces of gear) unplugged from the SIAB to the preamp..the hum disappeared.

so basically what i'm saying is, your probably alright on the Wharfedales you gave it a sound source and full volume= no hum.

you sound like a chasis to chasis type ground hum.

tried unplugging everything except the soundcard to the wharfedales.
remove all rackmount gear, pedals, anything etc... unplugged??

as you add stuff back in the chain you may hear the hum return...
 
That's the thing....there really is no signal chain to speak of...

I've got the Delta 1010's sound card intalled in my PC, then there is a 25pin cable that comes out of there to the Delta's 8 in / 8 out breakout box/rack, then two of the outputs of the Breakout box feed the Wharfe's......pretty basic...right?

Rick
 
Have you tried lifting the shield on your balanced cables? Either unsolder, cut them or use a DI with a ground lift. That's why I suggested balanced cables to begin with. By themselves they won't cure the hum, but you can lift the shield and break the ground contact between the two pieces, hopefully curing your hum.

Sounds like you may have a ground problem in your d-sub connector, but try lifting the ground on your cables first.
 
i'm agreeing with easychair at this point...equipment to equipment ground loopy. you've isolated it down now.
 
Hey guys, this weekend I tried to contact M Audio just to see if there was a common problem with the 1010's and grounding issues....

They emailed back with a lot of the stuff that you guys had suggested as well as some other stuff.... I'll post the text of the email when I get a chance.

Maybe this weekend I'll actually get around to "working" on this problem......maybe....

Rick
 
that'd be great if you post it. you never know when a noise may appear and having the info. handy always helps!
 
Well I just got done messing around with this stupid thing agian.......I followed the M Audio "Trouble Shooting" email, but even with everything disconnected there is still hum. No matter what I use the "ground Buster" on, it still hums.

I haven't tried lifting one of the sheilding wires from one of the cables yet, but at this point I really don't feel that it's going to do anything....???

Is it possible that I have developed a problem in my Delta that may require repair/replacement?? :mad:

Here's the text from M Audio:

This type of problem is usually caused by an electrical grounding problem in your studio.





GROUND LOOP TROUBLESHOOTING



All devices in your studio should be connected to the same ground. If this is not the case and one or more of the devices are getting their ground from somewhere else, (e.g. a different power outlet that is running on a different electrical circuit or the device has physically contact to a metal surface such as e.g. a doorframe etc.) and devices with different ground are connected to each other, this type of noise might occur.



There are different ways to fix this type of problem. The easiest and most cost efficient way is what is called a “ground lift” in order to interrupt the “ground loop”. Not all devices work correctly with lifted ground and might overheat and/or create an electric shock hazard. Before lifting the ground on a device, please contact its manufacturer in order to find out if this device will work properly and if it will create an electric shock hazard under these conditions.



Another and perhaps safer way to deal with this is with a ground loop isolator, you can get one of these at an electrical supply store.



Depending on the amount of devices in your studio, it might be hard to find the device that is causing the problem. For this reason we suggest the following approach in order to detect the source of the problem:



1. Disconnect ALL peripheral devices from the computer except for your audio interface and speakers. Printers, network, antenna cable to a TV Tuner card, audio cables etc. should all be physically disconnected from the computer.



2. Check if the noise is still there. If not, skip to step 3 in this guide. If yes, continue with number 2a.



2a. If you are using a Laptop, unplug the power supply and run on battery power. If this resolves the problem, you will have to lift the ground on the laptop’s power supply. (IMPORTANT: Contact the Laptop’s manufacturer to find out if lifting the ground is supported on this device).



2b. If you are using a Desktop computer, while you can hear the noise or have audio playing, turn your Monitor off, and then disconnect it’s power cable. If the noise is gone, you will have to lift the ground on the Monitor. (IMPORTANT: Contact the Monitor’s manufacturer to find out if lifting the ground is supported on this device). If the noise is still there, reconnect your Monitor, turn it back on and go to the next step in this guide.



2c. If your audio interface has a headphone output, disconnect the powered speakers or power amp with speakers from the interface and check if the noise is audible on the headphones. If the noise is gone, you will need to lift the ground on the powered speakers or amplifier (IMPORTANT: Contact the Monitor Speakers / Power Amp’s manufacturer to find out if lifting the ground is supported on this device).



3. If disconnecting all devices resolved the noise issue, start adding one device at a time and check if the noise reoccurs. Then, lift the ground on the device that made the noise problem reoccur. (IMPORTANT: Contact the manufacturer of the device you determined is causing the ground loop to find out if lifting the ground is supported on this device).







GROUND LIFT PROCEDURE:



IMPORTANT: Before you proceed, make sure that you have contacted the manufacturer of the device you intend to lift the ground on. If this is not supported for this device, lifting the ground can cause damages, serious injuries or death!



The best way to lift the ground on a device is to use a 3 prong to 2 prong adapter. These are available at electronic stores such as Radio Shack or Home Depot etc. Simply plug the 3 prong power cable in the adapter and the 2 prong end into the power outlet.



If this does not work:

I would recommend returning your device for testing/repair/replacement.



If you have had the device less than 30 days, please contact your original retailer about an exchange.



If this is not possible and you want to return your device to M-Audio for testing, please send us your mailing address and contact phone number via email and we will send the rest of the information you need for the return.



Also please let us know when and where you bought the device.



The Repairs department will be handling your Return after we issue you an RA number. Please contact them with any questions regarding Repair costs and shipment issues at: repairs@m-audio.com



I am fastly approaching the end of my rope on this one........it's just becoming too frustrating......


Rick
 
interesting.but not good.

Start over.
plug in other speakers to your pc/delta and verify there isn't any HUM? pc speakers whatever you were using.
IF good move on...

plug another source into your Wharfs and verify there's no hum?
IF good move on.....

Connect the pc/delta and Wharfs/speakers, with your new 3 wire-balanced cables, you get the HUM? Left and Right equally?
try the ground lift method.

But if at times, the HUM gets quieter or goes away?? It sounds like possible thermal problem..which is bad. Test would be TIME versus HUM.
 
WERNER,

Lifting the signal ground (not the AC ground) is the probably the most common way of cutting a ground loop. THE GROUND LOOP IS MADE BY THE GROUND CONNECTION BETWEEN TWO PIECES OF GEAR. Unless, of course, your M-Audio piece is fucked up.

You could try a hum eliminator from Ebtech. It's a transformer WITH THE SIGNAL GROUND DISCONNECTED.

Or, you could just LIFT THE DAMN SIGNAL GROUND ON YOUR BALANCED CABLE.

THAT IS ONE OF THE NICE THINGS ABOUT BALANCED CABLES.

I'M WRITING THIS IN CAPS BECAUSE YOU SAID YOU COULDN'T SEE WHAT LIFTING THE SIGNAL GROUND WOULD DO.

HOPEFULLY IT'S LARGE ENOUGH TO SEE NOW. LIFTING THE SIGNAL GROUND WILL PROBABLY HELP.


IF NOT, HERE IT IS EVEN BIGGER.



LIFT THE SHIELD ON ONE OF YOUR BALANCED CABLES!!
 
If I lift the sheild cable on one of my cables, wouldn't that be the same thing as what I had before,...a non sheilded speaker cable? (Sorry for being stupid on this one :o)

I'll try and de-solder one of the leads this afternoon just to make sure I've covered all of the bases. :)

Thanks,
Rick
 
WERNER 1 said:
If I lift the sheild cable on one of my cables, wouldn't that be the same thing as what I had before,...a non sheilded speaker cable? (Sorry for being stupid on this one :o)

I'll try and de-solder one of the leads this afternoon just to make sure I've covered all of the bases. :)

Thanks,
Rick
Click to expand...

No- in a balanced system, there are three connections. The shield is the only one connected to ground. The two that carry signal are not. In an unbalanced cable, one of the wires serves a dual purpose, both carrying signal and providing a ground path for signal noise.

Since it takes two wires to complete the signal path, you can't break the ground loop by lifting one conductor if you are using instrument or speaker type unbalanced cables- the circuit won't be complete and no signal will flow. In a balanced cable in a balanced circuit, the ground runs in it's own path, and the signal runs in the other two wires. You can lift the shield connection, and hopefully break the loop, and signal will still flow.

There is some debate about which end of the cable to lift, source or destination. Whichever works best is the best.
 
Well I un-solderd the sheild cable from one end of one of the cables (XLR side that goes intot the monitor) and it made no difference.....:confused:

The problem has been constant now for a couple of weeks and is showing no signs of letting up......

You think it's time to send the Delta in for a checkout/repair??

Rick
 
I just did another test...

I unplugged the "Host" cable from the Delta's breakout box (I/O rack). This breakout box is powered by a transformer(Wall wort). When I unbluged the Host cable(25 pin cable) the hum stoped. So I'm guessing that it's coming from either my PC or my Delta's PCI Card(???).

Rick
 
T-shooter club:

why do you keep saying its the Delta? did the Delta have a HUM before?
i missed something. Seems you never heard this hum until you hooked up your Wharfs.

Did you have this HUM before the Wharfedales?
What were you using before the Wharfedales, hook those back up...HUM?

I'd be hooking up other speakers to the PC.
And a standard CD player or something to the Wharfedales.
is this difficult to do due to tools or time?

your warrantys gonna be up before you get this thing partitioned out! :eek:
 
Warranty??? :confused: !!! -------> used off of ebay! :(

Here's the deal....

I never had my Delta installed until I received my monitors, I was waiting until I had "everything" before I set it all up. So before I received my monitors and installed my Delta 1010 I just had a SoundBlaster card in there with some Altec Lansing PC speakers (Which I still have the Altec's, and presumably could hook them up to the Delta's breakout box......I think all I'd need is a 1/4" to 1/8" adaptor(s)???)

When I power the PC down but leave the Wharfe's powered up, the hum goes away when the PC shuts off as well..........

Sorry for dragging this out for so long.............:o

Rick
 
i see. actually this is one of the more useful and interesting threads.

ground problems. buzz's and hums. its a break from shopping like a mad monitor gearhead.

what if both are good on their own and together they Hum? :eek:

kinda a incompatible matching of Brands?

so yeah plug your Altecs in the PC.
if its quiet... then plug your wharfs into the home hifi, like a standard CD player (line level).

Like i said, I recently took this old computer into my studio to do some RTA measurements on my monitors/room.
And the mic plugged into the SIAB, 48v phantom, then SIAB out went to the PC.
It hummed to, until I pulled a set of RCA jacks out of the back of the SIAB!!
the hum disappeared. believe me it was just luck and partitioning.
i don't have that much equipment. and the RCA jacks had nothing to do with the pc...but the grounds are all connected in a way...

Do I understand fully "why?the buzz went away?"
no. :confused:
 
M-Audio can kiss my @$$!!

I've tried twice now to contact tech support by phone and both times I was on hold for 45 MINUTES!!! I've never heard of such nonsense!!!! :mad:

They did reply back to one of my emails, but still.....they can't be THAT busy!! (Yeah honey,..I'll pick up chinese on the way home from my gruling tech support job.............hmmm...I wonder what that little flashing red light on my phone means?.....) :rolleyes:

I guess I'll have to run out to radio shack and find an adaptor for my Altec's. I can hook my Whafe's up to a CD player with out much effort...............time is the killer here..........MAN I WANT TO GET BACK TO RECORDING!!!!!!!

Rick
 
Yeah really! :(

It just ticks me off that I've waited sooooooooo long to put this "Studio" together, and now I've got this idiodic problem raising it's head.

I was only able to record that set of guitar sound clips and now I'm sitting idol....with a thousand projects looming over my head.........

Stop the insanity!!!! (or humming!)

Rick
 
Well I finally got a response back from M-Audio, it seems that their consensus is that I have one or more capacitors going bad and that I need to send it in for testing/repair/or replacement. :eek:

I emailed their repair dept. and asked about some trouble shooting tips or things to try like swapping out some caps or something (I'm pretty good at this from moding guitar amps n' such. ;) Maybe they'll come up with something simple so that I don't have to send it in.......and save a bit of time and cash as well...

here's hoping!!

Rick
 
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