Luna 2496 I/O box issues

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shockwave1312
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Luna 2496 I/O box issues

Post by shockwave1312 »

Hi, I am relatively new to the scope system but Ive had a Luna card for ages but just didn't use it and forgot i had it, until recently when I was clearing stuff out over lockdown, so now I'm getting my head around it and how the routing works, I've managed to route the I/O box as channels on traktor DJ and route to an external mixer , which works fine but I get this god awfull noise from the box ,it can only be described as low system noise/interference. even when I move the mouse about I can hear it ,is there any way I can stop it from happening? Is it something to do with the type of FireWire cable I'm using ? As I had to acquire that for the I/O box as it didn't come with one. Is it something to do with IRQ conflicts or something like that I don't know?
I also use a Novation X-Station keyboard as a soundcard sometimes and I don't get any that interference from it .

Hope someone can help ,thanks
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garyb
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Re: Luna 2496 I/O box issues

Post by garyb »

sounds like there is a ground issue somewhere in the audio chain. it's a hum or buzz, right?
the X-Station has nothing to do with that, if the noise doesn't go away when you don't have it connected to anything.

this is not a Scope issue, necessarily. whenever you have several (audio) things connected together, there is the chance of a ground loop. studio basics 101. :) try googling for info about audio ground loops.
shockwave1312
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Re: Luna 2496 I/O box issues

Post by shockwave1312 »

Hi, thanks for the reply .

It's not realy a hum or a buzz sound , its sounds more like electrical interference from my pc. If I could add an audio clip it would help.
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the19thbear
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Re: Luna 2496 I/O box issues

Post by the19thbear »

had the same with the luna box back in the day.
The combination of unbalanced signals no grounding and an old PSU caused issues.

My suggestion:

Unplug EVERYTHING from you computer. Only have mouse, screen and keyboard and the lunabox connected.
Nothing connected to the box. No synths etc.

Dont have anything else connected to the power plugs either. ONLY computer and screen.

Plug one thing into the power outlet and then connect it to the luna box.
The thing(s) you plug into the power outlet should all be connected to the same outlet. Also the same as the computer.
Plug your things in and power them on, one by one, until you find out what is causing the noise.

Then take it from there.


:)
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valis
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Re: Luna 2496 I/O box issues

Post by valis »

There are some discussions on the forums about how to bridge between balanced & unbalanced cables (at the same signal level) and/or where to 'break ground' on your cables to avoid various grounding issues. Probably worth visiting one of the threads where the diagram is posted as an image, as it should cover most situations. And point out little boxes that you can buy to do it for you, the lowest cost being PYLE units that run about $20 on amazon (US) and will work fine with RCA>Phono cables or adapters to avoid ground issues. I also recommended some EBTech units in those same threads, including one that you would put between your wall wart & power strip, or even a power strip and the wall.
shockwave1312
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Re: Luna 2496 I/O box issues

Post by shockwave1312 »

thanks I will give that a go and see how it goes, was also looking at ground loop isolators to put inbetween rca phonos to see if that would work too, I WILL get to the bottom of it lol

Thanks for the help
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valis
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Re: Luna 2496 I/O box issues

Post by valis »

That's what I was referring to, though these are phono (1/4") not RCA so you'd need cables that convert to & from to make it work. Since much of what we hook up is phono or 1/4", most likely you'd just have to convert the connection to the luna box and then normal cables from the other side to your gear.
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the19thbear
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Re: Luna 2496 I/O box issues

Post by the19thbear »

My suggestion is to wait with isolators etc. until you find out where the problem lies.
:)
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valis
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Re: Luna 2496 I/O box issues

Post by valis »

With ground loops that is how you fix the issue. Though starting with a proper star/octopus power distribution pattern and seprating wall warts, mains loops and computers into 3 different trunks is of course a good start. Oh, and any incidental lighting and non-audio gear can have an extension run into the other end of the house if need be :)
shockwave1312
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Re: Luna 2496 I/O box issues

Post by shockwave1312 »

***UPDATE***

Hi, I Tried unplugging everything and starting from scratch one thing at a time but with no avail . So I tried an RCA to RCA ground loop isolator I got from ebay, which was only £4 , and it worked perfectly, I have it connected between the IO Box and my external DJ mixer for use with traktor and it gets rid of the noise ,it also cancels out the noise when I'm listening to audio through the Pulsar or Luna cards and not directly listening to audio from the IO Box itself (for some reason you could still here the noise even when I wasn't using the box but it was still plugged in) .

Result!!

Thanks for all the help folks :D :D :D
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