USB Midi noise problem

Luther · Post by **Luther** » Sun Dec 02, 2012 7:21 pm

Hi,

I don't expect anyone to solve this problem, but I hope one does.

I have : Acer Aspire M7720 (6 Gb Ram) Vista 64bit , Realtek soundcard / Korg M3 xp 61

I have a noise problem: when I put the MIDI-USB cable in PC and M3 I get an irritating noise. The editor works fine, but that little noise destroys audio recording. The noise is in the audio-out of my PC, it doesn't get louder when I increase the audio level of the M3, it does get louder when I increase audio level of my Behringer mixer. When I disconnect the cable I don't have that noise.

Also: when I (USB cable is connected) go to Power Options (on PC) and press "change plan setting" the whole Power Options crashes and Windows Eplorer crashes and restarts again. When I disconnect the USB cable there is no crash.

This noise problem I also have when I connect my Korg Microstation USB cable to my PC.

I think it is a PC problem, but is there a solution? Perhaps it is a grounding problem (or perhaps not) but I don't have the possibilty to ground everything.

My conclusion - if things stay this way - is that I can't use the editor when I want to make an audio recording on my PC

Specifications PC:
http://support.acer.com/acerpanam/de...M7720sp2.shtml
http://azerty.nl/1-865-204673/acer-a...hd-4650-g.html

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Korg M3 XP 61 - Yamaha Motif XS6 - Roland RD-700SX - Korg Microstation - Yamaha HS 50M speakers

Bald Eagle · Post by **Bald Eagle** » Sun Dec 02, 2012 8:32 pm

It's possible that the USB cable is radiating interference. You could try a high quality shielded USB cable.

Luther · Post by **Luther** » Wed Dec 12, 2012 2:13 am

Thank you for your reply.

Your suggestion might be true, but it also might not be true, I just feel that it isn't the solution and therefore I will not invest in a better USB-cable. It costs some money and the risk of not helping feels to great for me.

But thanks anyway for thinking about my problem!

SanderXpander · Post by **SanderXpander** » Wed Dec 12, 2012 7:53 am

Sounds like a grounding issue. USB cables have a ground that can't be lifted like if you would use a DI with audio cables. Make sure at least all your connected equipment is on the same power group (ideally, split from the same wall socket). Hope it helps!

apex · Post by **apex** » Wed Dec 12, 2012 12:52 pm

SanderXpander wrote:Sounds like a grounding issue. USB cables have a ground that can't be lifted like if you would use a DI with audio cables. Make sure at least all your connected equipment is on the same power group (ideally, split from the same wall socket). Hope it helps!

EXPLAIN.

SanderXpander · Post by **SanderXpander** » Wed Dec 12, 2012 1:23 pm

What's to explain?

orpheus2006 · Post by **orpheus2006** » Wed Dec 12, 2012 2:35 pm

I'd also say it's a ground loop problem.

I experienced similar problems with other USB Audio-Interfaces connected to my notebook. I tried several ground noise reduction measures such as cutting the ground connection in a USB cable, testing with other "cheap" USB Audio Interfaces, switching in a ground loop isolator. These measures actually helped reducing the noise, but couldn't eliminate it entirely.

In the end I changed to a PCI/Cardbus based solution (RME Multiface), and haven't regret this decision.

synthjoe · Post by **synthjoe** » Wed Dec 12, 2012 7:49 pm

Do you use a USB-to-MIDI converter cable, or just a simple USB cable (both for the M3 and the MicroStation)?

Luther · Post by **Luther** » Tue Dec 18, 2012 2:06 am

I use a simple USB-cable.

@SanderXpander: Thx for reply. To connect everything I use to the same power group is a bit hard to realize. But if the noise is caused by grounding issues would it help to connect my equipment to the same power group? I mean: some reduction of noise is not really helpfull cause to still hear some noise is not good.

@orpheus2006: I googled on RME Multiface , a bit too expensive for me. But thx of course for reply!

All in all I haven't used the editor, do I miss a lot by not using it? Is it speeding up workflow and/or are there elements in the editor you can't do if you only use the M3 itself?

A solution I haven't tried is to install the editor on my laptop (I have a PC and an old laptop). Perhaps that might not result in noise during audio recording in my main PC. It is however not ideal.

______________________________________________________________________________________________________________
Korg M3 XP 61 - Yamaha Motif XS6 - Roland RD-700SX - Korg Microstation - Yamaha HS 50M speakers - Behringer Eurorack UB802 mixer
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synthjoe · Post by **synthjoe** » Tue Dec 18, 2012 6:09 pm

Luther wrote:I use a simple USB-cable.

Then you have a ground loop problem.

Luther wrote:@SanderXpander: Thx for reply. To connect everything I use to the same power group is a bit hard to realize. But if the noise is caused by grounding issues would it help to connect my equipment to the same power group?

Yes, that's pretty much the only thing you can try. Better said, you can take a thick wire and attach to a metallic part on both (synth and PC, and perhaps other gear in the chain), that should eliminate the potential difference between the two that is currently flowing through the USB and audio cables. Be careful, because if grounding on either (or the wall outet) is faulty, you can easily end up with some nice fireworks and your gear reduced to charcoal. So connecting everything to the same power bar is as close to the best solution as you get. Then putting the wire if the noise persist should not do much harm - nothing, at worst (except if you have a faulty power supply - but that should be the first thing to check and eliminate when noise problems surface, anyways).

There're also USB isolators on the net, but it might or might not work (speed is limited and other obstacles) and they're not exactly cheap. However, probably your best bet if you want to hold on to your gear.

Hope this helps.