high pitched humming noise

[bigmonster7]

My setup is MacBook with motu ultralite hybrid connected via USB (ac powered), softstep foot controller connected via USB.

The high pitch noise didn't start happening until I plugged in the softstep.

The noise stops when I touch my computer, guitar input cord, or the motu interface.

I also, as a work around, took a wire and attached it to the guitar cord (on the end of the cord by the input to the motu interface) and I have the other end of the wire under my foot.

Any help as what I can do instead of the wire solution?

Thanks

Scott

[agentwonderbread]

sounds like a ground loop to me...

[grooverb]

ditto

might be worth seeing if other people have similar problems, talk to the shop you bought it from, if its still in warranty maybe take it back. Doesn't sound very good though

[Rabalder]

I had a similar problem a few years ago. The noise went away when I plugged in the laptop´s power supply.

[bigmonster7]

I had a similar problem a few years ago. The noise went away when I plugged in the laptop´s power supply.

any updates here? my only solution so far is to plug in another guitar cord into the motu in or out, and place it in the back of my pant pocket or sock against my foot. That gets rid of the humm. I was wondering if it had something to do with have the motu plugged into the macbook via usb and external power at the same time?

[Pyro Z]

I know it's a pain, but try moving your set up and plug everything into different outlets on different walls. I bet your problem won't exist on at least one of them. Solution? Permanently move everything, or buy a power conditioner. Try using a surge protector if you have one laying around. Basically just experiment. Electricity is a finicky thing and does not play well with audio equipment unless it's perfect.

I'd have to say it sounds like a grounding issue, though.

[bigmonster7]

yeah, it's grounding for sure.

When I plug the guitar in, that is when the humm shows up. HOwever, when I touch my computer or the MOTU or the ends of the input jacks, then the noise goes away.

[bigmonster7]

Well, when the SS is not plugged in, the hum is not there. However, when I plug the softstep in, then the high pitch noise kicks in. Once again, only work around is that I hook up another guitar cord into the motu out, and run it into my sock against my skin.

I tried a USB hub, but to no avail.

To reiterate, this is my setup:

Macbook (no firewire)
MOTU (runs into my USB but is powered externally)
Guitar in to MOTU.

The only time the high pitch noise goes away is if I do the trick with the guitar cord to my sock, or if I am touching my computer or the MOTU. When I hover closer and closer to the softstep, the noise gets louder.

and yes, when I turn the LED lights on the foot pads off, the high pitch noise goes away..... but I want the LED lights!!!!


both MOTU and MAcbook are hooked up to the same power strip.

Softstep (runs into Macbook usb port.. duh!)

I even tried my crappy m-audio interface, and I get the same issue... but worse... The m audio one is usb powered.

help!

[3phase]

you need more skin contact.. wind the guitar cord around a warmer bodypart an sit on the cable so that it gets some pressure.. that should give you some kind of interim grounding point..

better would be to dig a hole.. and sit on the cable in there.. thats a real ground connection..if you dont like to sit in the hole al the time nail the cable to the ground.-. but use a long nail.. 9 inches are not enough.. good is something inbetween 30 and 100 inches... and use a thick guitar cable... half a squar inch is nice.. that on a 100 inch nail would remove any noise from your system..

when ther is no place to dig a hole ask your local electrician wheer to find a grounding point in your house.. but diggin and nailing is of cause the most direkt way to get to the ground

[bigmonster7]

Also, to reiterate. When I have the softstep plugged into my macbook, without my guitar plugged into my MOTU ultralite USB interface, then there is no noise (high pitched noise) from my feet hovering over the softstep.

When I do plug my guitar into the MOTU, or better yet, when I touch the input (end of the guitar cord that is suppose to go into the guitar) while the MOTU is plugged into my macbook (and setup in ableton as my input and output) I hear the same high pitched noise.

I tried changing the output to come directly from my macbook, but still have the input (my guitar and vocals) come through the MOTU.

So it's weird. The MOTU isn't causing the noise, but it has to be involved in order for the LED's to start causing the noise.

[savyurrecords]

Grounding issues are almost always weird. You can try to be logical about it but to tell you the truth basic troubleshooting is the only way through. You need to keep changing things one at a time. I have read plenty on grounding and the only thing that seems to work is good old trial and error.\

Have you tried someone else's guitar? I know about the cable being unplugged making noise, but still you need to try and change everything one thing at a time.

It can be more fun when your guitar picks up a radio station louder than your playing! Though that is RFI it is still one of those strange electrical issues.

Good Luck


PS For those with the radio station in the guitar the easiest solution is a ferrite choke. Essentially a piece of iron you wrap around the guitar cable at the amplifiers input.

[borg nagar]

This is a common problem for every musician. It's a ground loop for sure. 50hz hum in Europe and 60hz hum in US (depending on the electricity network). [Though I wouldn't say it's high pitched those being bass frequencies...]

Here's some solutions! Try using a DI-box with ground lift switched on in between the guitar and whatever you plug the guitar into. Something like: http://www.thomann.de/gb/behringer_di100_ultra_di.htm for example.

Another option would be getting a galvanic isolator from your local electronics shop.

I had this problem with my pc laptop all the time. So the third and the one solution that everyone used to give me is: buy a mac. I did. I still have a lot of problems, but not with ground loops.

[bigmonster7]

here is a recording of the noise when I have the LED's on. When I turn off the LED's the noise goes away. It also goes away is I touch the computer, or move my foot away from the softstep. I demonstrated all of those in the recording.

http://www.sendspace.com/file/32shga

[Tone Deft]

YO!!! LIKE SO MANY PEOPLE HAVE WRITTEN, IT'S A GROUND LOOP PROBLEM!!!

connect all your stuff into the same power outlet, get them on the same circuit breaker, etc.

[bigmonster7]

YO!!! LIKE SO MANY PEOPLE HAVE WRITTEN, IT'S A GROUND LOOP PROBLEM!!!

connect all your stuff into the same power outlet, get them on the same circuit breaker, etc.

I've done that. did that from the start. The only thing that isn't powered by the same power strip is the softstep. This is powered via usb. Everything else is powered by the power strip.