Friday, June 10, 2005

SPDIF

S/PDIF is a digital format for sending audio. I've heard of it, but never done any thing or had anything that used it. it can be used in two flavors. optical or electrical (rca). the new DVD player has a digital (S/PDIF) out, and this got me thinking. awhile ago, a friend of mine gave me some digital speakers. what an oxymoron. how can speakers, something that generate compression waves (in the analog realm) be digital? have no fear. they still employe analog, it is just contained to the amplifier in the speaker. the link from the source to the speaker is what is using digital.

I plugged the speakers in with a standard RCA/RCA cable (usually used to plug your old style VCR into the TV before the advent of S-Video. this got me thinking.. the p4s800 motherboard I purchased over a year ago may have had a digital output. I dug through manuals online because I"ve lost mine, and i'm to lazy to actually stick my head around and look on the back of the computer. I thought it was particularly interesting that I was able to remember the model number of the motherboard yet be to lazy to look at it. maybe I am a geek. the online manual confirmed my board had SPDIF output. I plugged the cable in and NOTHING. how disapointing. then it dawned on me it must be a driver issue. 10 minutes later.. NOTHING. then it dawned on me it must be a BIOS issue. a reboot and a looksee and NOTHING..

hmm.. how weird. whats the point of an SPDIF output if it doesnt' actually do anything? when I restarted the machine it magically worked. it must be some autodetect on the hardware level to see if its plugged in, or autodetect in windows or something. soo....... digital output.

whats the downside? I use line in, and the soundcard does not automaticaly resample the line in and put it out the SPDIF. I was looking for a fullduplex utility to buffer my line in, and put it out (in essense using the computer to convert from analog to SPDIF) but I haven't found a utility in the 5 minutes of looking. all I really need is something that can record and playback at the same time. kind of like tivo for audio. if anyone sees it let me know.

now to find a few digital buffers, some resistors to cut the voltage back to 1vpp, and an isolation transformer from an old network card and I'll make an SPDIF with two inputs (one for the DVD, and one for the computer) so I don't have to pay 100$ or more for a stupid receiver that can switch SPDIF.

1 comment:

lizzy said...

Hmm...I have to tell you that I don't really know what this means. But, I just wanted you to know that I read it and feel smarter. Now, if I can only work this new found information into a conversation...