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Hi, Joe and Lou,

This is complicated. First of all, on the device in question, the S/PDIF 
signal appeared on what's called a mini-TOSLINK adapter which is a 
combined jack with the analog line output (no control feedback beeps on 
this connector which sets these apart from most portable CD players). It 
seemed in the mid 1990s, Sony made this link available so you could use 
the portable CD player to play a CD and a minidisc recorder to record 
the CD, all in the digital domain. Ooops, my MD doesn't sound quite like 
my CD, even though it's a digital clone...OOOPS, it's not a digital 
clone because the MD recorder uses ATRAC compression in various 
flavours. Later, MD recorders could record full-resolution uncompressed 
WAV files, but I never owned one of those and don't know if it had the 
optical input. Sadly the portable players did not have optical outputs, 
so we could infer this was the major designed-in use for these 
connectors. The home units had optical outputs--at least some of them. 
The last portable made, which I've written about previously, had a USB 
connection permitting you to rip many flavours of MD.

Here are some painfully boring details about digital audio interfacing.

To be totally specific, TOSLINK is available in two flavours:
    Standard JIS F05 (HIS C5974-1993 F05)
    mini
Normally, these fibre optic cables carry S/PDIF audio signals.
BUT, JIS F05 connectors are also used to carry the incompatible ADAT 
Lightpipe 8-channel signal.

TOSLINK is described here:
http://en.wikipedia.org/wiki/TOSLINK

S/PDIF is described here and it is important to note that for 2-channel 
stereo, it is a consumer version of AES-3.
http://en.wikipedia.org/wiki/S/PDIF

S/PDIF, as implemented through a host of other standards, can also carry 
compressed multi-channel audio like DTS or Dolby Digital.

There are adapters on the market such as the currently available M-Audio 
CO2 which convert optical to coaxial signals and vice-versa.
http://www.m-audio.com/products/en_us/CO2.html
I actually ended up with two of those plus a Core Sound unit that also 
interfaces with the D8 DAT Walkman.

The converters are transparent to the protocol and are strictly media 
converters such as those that go from 100 BaseT to 100 BaseFX Ethernet 
connections.

Here are most of the common signals/connectors:

PCM Stereo S/PDIF:
    75 ohm coax on RCA
    optical fibre on F05 (TOSLINK)
    optical fibre on mini-TOSLINK
Compressed Digital Multichannel:
    --Dolby Digital
    --DTS
    75 ohm coax on RCA
    optical fibre on F05
PCM Stereo AES3
    110 ohm twisted pair with XLRs
     (note AES has just standardized a different XLR for digital, but 
there can be dual-versions)
PCM Stereo AES3ID
    75 ohm coax on BNC
ADAT Lightpipe
    --8 channels at 44.1/48
    --4 channels at 88.2/96
    --2 channels at 176.4/192 (sometimes)
   optical fibre on F05

You generally can connect AES3 and SPDIF signals together. Some metadata 
gets confused. Many pro devices have a setup for whether the AES is pro 
or consumer.

Yes, Lou, so many standards...but aren't you glad you asked, Joe 
<smile>? I sort-of knew this, but I checked with the two Wiki articles 
to make certain I was clear and did not forget anything.

Cheers,

Richard

On 2012-01-31 8:29 AM, [log in to unmask] wrote:
> Richard,
>
> So was it SPDIF or optical? I thought they were 2 separate things.
>
> joe salerno
>
> On 1/30/2012 11:07 PM, Richard L. Hess wrote:
> --those had SPDIF optical outputs!
>
On 2012-01-31 9:50 AM, Lou Judson wrote:
> SPDIF can be coax or optical...
>
> Optical can be TOSLINK or ADAT
>
> Coax can also be analog (RCA/phono jacks.)
>
> RCA jacks can be speaker connections in lo fi gear.
>
> So many standards!
-- 
Richard L. Hess                   email: [log in to unmask]
Aurora, Ontario, Canada           (905) 713 6733     1-877-TAPE-FIX
http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.