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I'm having a hard time finding an spdif cable with mini plug on one end(Luna card) and rca(M-audio Tampa) on the other end. I'm wondering what people are using to connect the digitally. Are people using adapters?

Thanks,

welcome

yes, you need an adapter - mini stereo to chinch female and 2 cables (chinch male) as they are used for video connection. Those will have the required 75 Ohm impedance, which IS important.
A 'regular' mini-stereo to chinch cable will spoil the digital signal, an effect the s/pdif error correction will try to compensate, so it may not be obvious immediately. The sound may be slightly blurred to distorted, sometimes with faint crackling.
You should take the opportunity and use a wrong cable (which you probably have laying around somewhere).
It's a good exercise to sharpen your ears for the sound of digital problems

cheers, Tom

When I had Luna I just made myself a little adapter cable out of Radio Shack parts. Worked fine. Annoying though isn't it.

Thanks for the response. I did try a cable I had lying around and did notice crackling and I wasn't too impressed with the sound. I'm glad it's the cable not something else. What do you mean by "chinch"? My preamp is mono and only has one RCA output connecter. Would I still need a stereo cable?

Thanks,

'chinch' (probably spelled wrong) but spoken like this (in germany ) is the same as RCA technically.
I dunno the analog ins of the Luna, but they are probably RCA, so a 1 line cable would be enough, but they are less common.

the crackling of the s/pdif port could also be related to a wrong master/slave setting in the sample rate dialog. Either Luna or the M-audio has to be master, not both.

cheers, Tom

<font size=-1>[ This Message was edited by: astroman on 2004-09-02 19:37 ]</font>

How do I know if my adaptor has the right impedance? I don't hear any crackling.

Impedance is less important with modern high voltages unless using extremely long cables. I'd be more concerned that its properly shielded and not a cheap radio shack deal...

the SPDIF is 1/8” stereo mini jack to 2 x RCA. these can be found at a Radio Shack store or any electronics store.

or simply can be made at home.

these are standard 75 Ohms.