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Re: I/O device with multiple *independent* SPDIF ports?

That sounds cool -- which FW device is that?

What is the FireWire interface with 32-bit integer format for digital audio (SPDIF)? Does it need a special driver to work with a Mac?

It's RME Fireface 800. According to User's Guide there are drivers for both operating systems on the disk, and installation procedures are well described.

P.S. DTS only uses the lower 14 bits of the audio sample, so that the digital noise is at -12 dB. Seems like a shame to lose 96 kbps of bandwidth.

Not only that! If you look at the actual content of SPDIF when transmitting DD or DTS then you'll see that large parts of each block do not transmit any information at all. All samples are set to zero. This is because compressed data, even for 6 channels, require much fewer bytes than 2 channels PCM for corresponding time length. Each block in SPDIF is of fixed byte length, and for given rate, also of fixed time length. Therefore they have to fill it with zeros when actual data for this time length is shorter. Talk about wasting bandwidth! All this seems to steam from the fact that SPDIF was designed to transfer digital audio *signals* as opposed to *data*. Then someone come up with the brilliant idea of sending compressed data through it. Then AES adopted all this, and now we are where we are.

Regards/Mikael

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References: 
 >OT: I/O device with multiple *independent* SPDIF ports? (From: Stephen Davis <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: "Mikael Hakman" <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: Stephen Davis <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: "Mikael Hakman" <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: Brian Willoughby <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: "Mikael Hakman" <email@hidden>)
 >Re: I/O device with multiple *independent* SPDIF ports? (From: Brian Willoughby <email@hidden>)



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