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by TheAmazingRace 176 days ago
Thanks. Of course, a quarter of a century or so after these went out of production, this isn’t exactly useful information, but fun nonetheless.

That’s the biggest issue with MIDI. No matter the equipment you had, you were never sure what the musician intended the composition to sound like, unless they explictly mentioned the exact synth used in the metadata, like a Yamaha XG synth or a Roland SoundCanvas. I really appreciated how compact the file sizes were, but I can definitely understand sticking with PCM formats off audio CD or even WAV/AIFF/MP3 back then, depending on the application.

So possible fun tidbit about SPDIF. Coaxial SPDIF, despite seeming more old school compared to its optical TOSLINK counterpart, could achieve higher bit depth and frequencies (sometimes up to 24-bit/192 kHz!!) whereas TOSLINK was officially limited to 16-bit/48 kHz, with manufacturers pushing as high as 24-bit/96 kHz off spec. Perfectly fine for your average music enjoyer of the time, but still an interesting limitation.

On mention of DAT and MD, those were two formats I would have loved to get into, if they weren’t so compromised due to RIAA shenanigans or too pricey. Such is life I suppose.

Yeah I’d say overall, I haven’t touched SPDIF in a long while myself. My current TV uses an eARC over HDMI soundbar setup and my PC connects using good old fashioned 3.5mm audio jacks.

1 comments

One neat thing about specifications like toslink is how flexible they are -- or perhaps, how arbitrary they are.

At the core, both coaxial and toslink were just transport mediums for the same SPDIF bitstream. One used copper, and the other used bendy plastic fiber optics.

And yeah: Toslink was more-limited on bandwidth, by specification.

And one would think that this would be because the optics are not so good (they're definitely not so great), or something.

But then: Alesis showed up with ADAT, and ADAT's Lightpipe could send 8 channels of 24-bit 48KHz audio over one bog-standard Toslink.

They used different encoding, of course. Even at a very low level, rather than detecting a rising edge 1 and a falling edge as 0, it detected any edge as 1 and a lack of an edge as 0. This did let them pack a lot more bits in.

But in doing that (and whatever else they did), they multiplied the functional bandwidth of a lowly Toslink cable by a factor of about 6 -- using the same optical components at each end that Toshiba sold, and the same Toslink cable from the big box store.

I think we've beaten sound cards and SPDIF to death here. :)

It's been fun. Perhaps we can do this again some day.

Thanks again for the entertaining back and forth. Hope to see you again around these parts soon.