[lan]

There is a perceptual difference even in short distances in my experience. Most people can't really answer how much since loss or degradation since they don't have any equipment to test these things.

I'm sure there are various qualities of optical cable. Just get a glass one and be done with it. SonicWave glass toslink from cablesamerica.com .5m is ~$24 last time I checked.

 

[HiGHFLYiN9]

There really isn't much use in debating the science of optical cables, it won't come to any worthwhile conclusion. One has to TRY the glass optical cable before making a conclusion about it. I agree with lan here, its cheap enough just give it a shot.

 

[Glassman]

it shurely has something to do with triggering the input optical sensing logic in the right time.. under the sea, there's computer data carried and precise timing is a non-issue due to all those memory buffers in repeaters etc. as long as data doesn't corrupt it's okay.. but the situation with S/PDIF streams is way different.. jitter guys, jitter is to blame here, apparently glass optical do better in precisely receiving 1s and 0s in time.. I believe in glass optical even though I never used one, not just plastic one

 

[Alereon]

Cheap TOSLINK Optical cables are frequently used to carry Dolby Digital AC3 compressed audio in the home theater. If there were any bit errors at all in the stream, they would be instantly recognizeable as the decoder hit a corrupted frame. The absence of these bit-errors is proof that upgrading the cable in your TOSLINK Optical system is not going to improve audio quality at all.

 

[sbulack]

I am really happy with Sonicwave Glass Toslink cables, AND with the price for which I get them at: www.av-cables.net
$35 for 1m, $45 for 2m, $50 for 3m,
about what I pay for an IC.

I'll let you guys debate the science. I'll spend my time enjoying the music I get from my rig with the Sonicwave Glass Toslinks.

 

[gort]

Quote:

Originally Posted by Alereon Cheap TOSLINK Optical cables are frequently used to carry Dolby Digital AC3 compressed audio in the home theater. If there were any bit errors at all in the stream, they would be instantly recognizeable as the decoder hit a corrupted frame. The absence of these bit-errors is proof that upgrading the cable in your TOSLINK Optical system is not going to improve audio quality at all.

Wouldn't DAC correct any errors?

 

[Glassman]

read my post once again if you don't understand well.. there are no bit errors whatsoever (shouldn't be at least), but there is jittery signal from which master clock for DAC is derived using PLLs, the cleaner signal goes to PLL, the better master clock goes to DACs and this actually can be heard..

 

[ampgalore]

I am waving my white flag. All this techno talk reminds me of why I never went into engineering.

 

[Alereon]

Quote:

Originally Posted by gort Wouldn't DAC correct any errors?

In my example, the AC3 decoder is responsible for handling bit-errors, and in a case like this, the only way it can respond is by dumping the entire audio frame. This will result in an audible pop, click, beep, or skip in the audio signal, depending on how it chooses to handle the error.

Quote:

Originally Posted by Glassman read my post once again if you don't understand well.. there are no bit errors whatsoever (shouldn't be at least), but there is jittery signal from which master clock for DAC is derived using PLLs, the cleaner signal goes to PLL, the better master clock goes to DACs and this actually can be heard..

That's not how it works. Jitter is only a factor if it causes a bit error in the stream. For example, jitter on audio CDs is an issue if it's bad enough that the audio stream gets mis-decoded and you get corruption in the data being read. A weak, noisy, jittery optical signal that's just BARELY clear enough to be properly rendered by the detector is going to be perfectly identical to the reference, insane quality signal. This is the magic of digital technology. Output is always perfect unless you get a signal error. We know by the fact that cheesy optical cables work for compressed digital streams that jitter isn't bad enough to cause bit-errors, thus it isn't a factor in sound quality.

 

[Zoide]

Well, I guess the whole point of the jitter matters/does not matter is this, but then why bother with buying an expensive transport or whatever if you end up connecting it to a good external DAC? By this logic you could almost say that a Sony PCDP would give you the same sound than a Meridian or whatever (provided their optical out goes through the same external DAC). At the same time, the optical cables between the components would make no difference either?

 

[ampgalore]

Anyone done a double blind test with toslink cables?

Anyone done a double blind test with cheap Sony transports and expensive meridians?

I know double blind tests are not allowed, but that's the only way you can tell.

 

[Dane]

Quote:

Originally Posted by Alereon That's not how it works.

Huh!? I thought that was exactly how it worked

The DAC might however isolate the jitter from the analog output by employing more or less refined buffering and re-clocking methods. I think this issue has been debated many times before. The search is your friend - if it works

ampgalore: Just do a regular blind test, that's allowed

 

[zum]

I recently bought a toslink cable TK40 from vekoy.com, a Finnish electronics supplier. I really wanted to know whether a glass toslink cable is really better than other cables.

The product page.

The new cable is half a meter long and pretty thin, only 2 mm or so in diameter. It's covered in black plastic and is quite flexible.

Here you can see the new toslink cable in comparison to my trustworthy Glass Toslink cable (the sort you can buy from e-bay with around $30-40, with text "Glass Optical Fiber"). As you can see, it's quite a bit more lightweight!

(The smaller one is the new one.

The new cable has very fine resolution, stunning impact and well-defined bass. Every single detail that I've ever had the pleasure to hear through my Glass Toslink-Benchmark-AKG K340 combo is delivered with no less than perfect precision through my new TK40. It's ever as enjoyable as my old system was.

If I have to find a complaint about it, well, it certainly doesn't look as good as glass toslink. (Unless you like really minimal). But that only matters, I think, if you spend a lot of time connecting and disconnecting cables. But at the end of the day, you shouldn't judge a book by its cover, nor a toslink cable by its appearance. Sonically the cable leaves nothing to wish for. (Although I can't say how much the Benchmark compensates for its possible weaknesses.)

Plus, what no other cable absolutely cannot ever beat is the price-performance ratio - the cable cost only around $3.

 

[yammy1688]

Keep in mind SPDIF is a connectionless, non error-correcting protocol, so those 1's and 0's can get lost in the transmission and neither would care.

Quote:

Originally Posted by meat01 Radio Shack is fine, you're talking about 1 and 0's. Spend your money elsewhere.

 

[yammy1688]

This is because you have higher layer protocols such as TCP which handle acknoledgements and retransmission of lost bits, therefore there is NO data loss. SPDIF just sends the bits and that's it.

Quote:

Originally Posted by ampgalore Fiber-optic communication cables run in the lengths of hundreds of thousands of miles, and carry GIGANTIC amounts of data, MUCH more than the amount of data contained in stereo signals. Of course there are signal boosters along the way. For a mere few meters of optic cables carrying stereo signals, I don't see how the quality can change appreciably between glass and plastic.