Never been one to let the carrier drop

Okay, first of all, in the Alesis AI-4 manual it states that a SPDIF signal can be fed to a AES jack by using a matching tranformer. After a quick web search for SP/DIF to AES matching transformers, I conclude that no commercially available product exists, and (as one could almost predict) reach for a microphone matching transformer, assuming that SPDIF must be about 48khz in bandwidth and will pass through a audio transformer just fine.

Then later I think to read about SP/DIF’s encoding system.

No.

SP/DIF is 3 !Megahertz! in bandwidth. To carry a 48khz signal! Fer crissake, I’ve worked on computer LANs that used less than 3 megahertz!

So, I guess my question for the audiance is, what kind of matching transformer does one use to match a low-impedence 3Mhz signal to a high impedence 3Mhz signal?

At this point, I’m tempted to get four AI-1s, just to have the whole problem over and done with. It *almost* works without a matching transformer – the audio is there, all pretty and clean and happy, and then suddenly ‘click-click-click’.

I’m wondering if I got a metal-can RCA to XLR adapter and used SP/DIF approved cables to go from it to the SPDIF jack if things would work better. A lot of the time I run SPDIF on regular RCA cables on the theory that it was 48khz, how far wrong could you go – but now that I’m discovering that the stuff is basically video, bandwidth wise, I’m rethinking my approach somewhat.

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I’m having a lot of trouble with one of my systems here. it’s a win2k machine running one IDE and one SATA drive, with a firewire interface board and a high performance video card in it.

One of the things I’m doing with it is editing video. It has a 30G and a 250G drive in it. Currently, the 30 gig clocks in at about 9000k/sec, and the 250G clocks in at about 1500k/sec. I know that larger hard drives tend to be slower, but by 10:1? Can someone please explain to me what I’m doing wrong? I installed the drivers that came with the motherboard…

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I can’t decide how I feel about this new drug that I’m on. On one hand, it certainly makes it easier to work on things continously, and to interrupt tasks and return to them. On the other hand, it also makes me constantly aware of all the things that I should be doing that I’m not. I never realized before how poorly adapted to the ‘adult’ world I am. (In fact, I suspect all of humanity is poorly adapted to it and that certain individuals in places of power like it that way – I guess we’re more tractible that way)

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