You can use a mini toslink to regular toslink cable
And toslink can carry all three audio signals from the 5.1 system ?
Yes, you'll also need a 5.1 receiver/amp. You can pick up a decent Sony for around $150-200USD.
And toslink can carry all three audio signals from the 5.1 system ?
I'm not exactly sure what you mean by three audio signals, but yes it will carry 5.1 audio in one cable
Most 5.1 speaker sets have 3 cables you need to plug in from the system.
Not so much these days - Optical or HDMI usually.
You can use a USB device to provide 5.1 analog (3 cables) output. Just be sure that the device is compatible with your Mac.
Your Mac has an optical 5.1 output that coexists with the analog 2-channel outlook. In most cases you need an minitoslink to toslink optical cable as well as some powered speaks that have optical in.
After much research I've decided that it would be cheaper to sell my Mac, build an equivalent PC and buy a surround sound system. You'd think such an entertainment minded company would actual support standards.
Oh wait, thats right, Blu Ray is a bag of hurt, so I guess surround sound is too.
Macs have never had analog output more than two channels. Since the transition to Intel chipsets all Macs have had optical audio output, which is the defacto standard for all home theater systems (some have coaxial audio, but digital nonetheless) for 5.1 Dolby Digital or DTS audio. It also provides far superior dynamic range than does analog 6 channel audio.
Blu-ray is a "bag of hurt" because of its intrusive nature in the kernel of the OS. 5.1 is easy on Macs, but you need a receiver with optical input. You are wanting inferior audio technology, which Apple won't ever use.