Optical digital interconnect

I have heard a difference between optical cables.  The one I use is the Wireworld Supernova 7.  It was not cheap, but was more natural with musical detail than others I have tried.  Many, I think, have expressed a preference for glass fiber over plastic.  Try and see what you think.  Depending on the rest of your system, it may or may not matter.  If you are not concerned about achieving every last bit of "audio quality" then save your money or buy more music, etc.

There are technical reasons for these (and other) cables to affect the sound.  So-called "digital music" is actually transmitted between components as an analog, radio frequency, pulse waveform.  Any distortion of the waveform can affect the final musical result.  The notion of "bits are bits" is a naive misunderstanding of the technology.

Charlie

PS:  edit - I see you have a revealing system, so you would likely benefit from the best possible cabling and racking.

Generally regular digial connects are thought to be better than optical.

Optical has one advantage though - by removing a galvanic connection between components it can help with not transferring interference.

There is also a sampling frequency limit imposed on optical connections. If I recall correctly  it's 96kHz / 24 bit.

Potentially, an optical connection should offer a number of advantages over coaxial. However, in practice most optical connections are hamstrung by the TOSLINK connections and invariably sound worse as a result. 

Thanks for the information, perhaps there's some clarification to another question I have, which I will start a new thread for as it goes off on a tangent from this.

The usually accepted reason for the differences is that the jitter on most Toslink receivers is significant,  The better the optical interface between the light pipe and the optical detector is critical as if the signal is weaker it's control of the resulting signal timing is less precise.

More jitter in the output from the link means more extreme re-clocking of the digital data, hence more variance in the re-clocked signal, so more work and more digital noise.

CharlieP posted:

I have heard a difference between optical cables.  The one I use is the Wireworld Supernova 7.  It was not cheap, but was more natural with musical detail than others I have tried.  Many, I think, have expressed a preference for glass fiber over plastic.  Try and see what you think.  Depending on the rest of your system, it may or may not matter.  If you are not concerned about achieving every last bit of "audio quality" then save your money or buy more music, etc.

There are technical reasons for these (and other) cables to affect the sound.  So-called "digital music" is actually transmitted between components as an analog, radio frequency, pulse waveform.  Any distortion of the waveform can affect the final musical result.  The notion of "bits are bits" is a naive misunderstanding of the technology.

Charlie

PS:  edit - I see you have a revealing system, so you would likely benefit from the best possible cabling and racking.

I think you'll find that signals go down an optical cable as light and there will be less attenuation in the signal. However, cables can be manufactured in different ways and light either sent down the middle or bouncing off the sides as it goes along. It also has to be translated at start and end and no doubt all these things contribute to quality.

MediaMagician posted:

I think you'll find that signals go down an optical cable as light and there will be less attenuation in the signal. However, cables can be manufactured in different ways and light either sent down the middle or bouncing off the sides as it goes along. It also has to be translated at start and end and no doubt all these things contribute to quality.

To the best of my knowledge all optical cables used in the Hi-Fi industry are multi-mode fiber links, so it's always "bouncing off the sides" (actually it could either be reflected off or be bent away from the sides), but with the short distances involved and very low data transmission rates (at least in comparison to the velocity of light) this is completely irrelevant.  Also there's no translation at either end, the signal sent is S/PDiff - same as a coax digital connection.

The real source of variance is the interaction of the coupling of the fibre to the receiver and the optoelectronic quality of the receiver.

Huge posted:

MediaMagician posted:

I think you'll find that signals go down an optical cable as light and there will be less attenuation in the signal. However, cables can be manufactured in different ways and light either sent down the middle or bouncing off the sides as it goes along. It also has to be translated at start and end and no doubt all these things contribute to quality.

To the best of my knowledge all optical cables used in the Hi-Fi industry are multi-mode fiber links, so it's always "bouncing off the sides" (actually it could either be reflected off or be bent away from the sides), but with the short distances involved and very low data transmission rates (at least in comparison to the velocity of light) this is completely irrelevant.  Also there's no translation at either end, the signal sent is S/PDiff - same as a coax digital connection.

The real source of variance is the interaction of the coupling of the fibre to the receiver and the optoelectronic quality of the receiver.

Huge,

Why is it that glass fiber seems to be prefered to plastic?  (A preference to which I concur, based on my statistical comparison of two cables ).  Is it dispersion of some sort along the cable?  Or is it the quality of polish at the ends?  Or something else?

Charlie

the polished surface and the connector  fitting can make a difference.  spent time terminating bt lines in the80s. ugg...cable needs to be long enough so a natural loop between the 2 units can be achieved

+1 to Audio1946's answer.  Also my experience from designing optical scientific instruments.