Korg Forums

Hi All,

I have a Lexicon Alpha Studio audio interface that connects to my Mac via USB and the audio cables connect to the Korg Microstation. I record in the free Cubase LE 5 that was supplied with the Lexicon and the audio recordings are really crisp and exactly what I need.

However, as soon as I connect the Mac to the Korg via USB cable to control the Korg via MIDI, I'm getting a buzz like a ground loop sound.

I don't understand why because if I disable the sound connections in Cubase I just get the Monitor input (sound direct via Headphones from the Lexicon) that sounds crisp so the problem must be from the Lexicon to the Mac.

Any ideas.

Thanks.

had similar problem on desktop with a guitar pedal/usb interface changed to back usb no problem. or if put through my keyboard for computer usb (so if you have a usb interface or something with a usb on (to go in between usb and comp)

Other thing to try is try keyboard in different socket in room, that worked too

You need a Regulated power adapter!
see:
http://www.korgforums.com/forum/phpBB2/ ... d6d3571fb3

Thanks for the tip, but I know very little about electronics. Going to send a support form to Korg to check this out to see why one wasn't supplied originally or which is the one that Korg recommend. Still under warranty and wouldn't want to flat-line it at this stage.

The adaptor supplied has a clip-on 3pin plug (UK).

Cheers.

I've had an email from Korg Support regarding the ground loop and the microstation software editor having the option to edit the onboard sequencer information on a PC/Mac....

----------------------------
Dear *******,

It seems that you are under the misconception that the issue is caused by the microSTATION itself which it is not. When I mentioned that USB ground loops are a common problem, I was not referring specifically to the microSTATION. For example, if you performed a Google search “USB ground loop” you will come across hundreds of hits relating to all sorts of combinations of products.

Here is a little more information on what ground loops are how they are most often dealt with (from Sound On Sound’s website - http://www.soundonsound.com/sos/dec08/a ... 1208_2.htm):

“A ground loop occurs when there's more than one ground path between two pieces of gear, and nowadays is comparatively common when connecting an earthed computer via an audio interface to an earthed mixing desk or power amp. As I described in SOS July 2005 ( http://www.soundonsound.com/sos/jul05/a ... 0705_1.htm ), there are three common ways to break such loops safely (depending on whether or not the gear you're using provides balanced inputs and outputs), and they are: using balanced audio cables; using pseudo-balanced audio cables; or using a ground-loop eliminating box containing an isolating transformer, such as the ART Cleanbox II, reviewed in SOS August 2005 and typically costing under £35 in the UK or around $50 in the US.”

As you can see, there are different ways of dealing with ground loops. Since your audio interface does not seem to have balanced inputs (nor has the microSTATION got balanced outputs), the DI box method suggested would be one of the safest, cleanest and cheapest ways of doing it. We cannot recommend using any other power supply unit other than the one provided with the microSTATION.

With regards to the microSTATION software editor, I am unsure about what makes you feel it has been abandoned but that is not the case. Having said that, it was not designed to provide sequencing capabilities like the hardware itself so I believe this is unlikely to change in the foreseeable future.

Best regards,

***** *******
KORG UK LTD

Basically, I get the feeling that they are not interested.

Very disappointed with Korg, I expected more!

ie: I wanted a cheap solution to what I think is still their fault not mine.