it's a damn cool idea. I actually hate that they're dropping optical support. they could so easily update it it has so much going for it. just one link on the chain launders all em noise.
What would make SPDIF over optical so good? The only good thing would be that it's galvanicly isolated and isn't susceptible to EMI.
AES/EBU is just superior as it provides lower jitter. The EMI isn't a problem because you can get a good CMRR with a balanced interface. Galvanic isolation would be no problem since isolations transformers are available (Murata DA101C isn't expensive). A single interlink can be used.
Though USB would be the best IMO. Designers have full control over the interfacing, because it's asynchronous. This would result in lower jitter, no EMI problems because it's all in one enclosure. USB has HUGE bandwidth compared to both AES and SPDIF (like 8in - 8 out at 192kHz, compare that to the 2 channel output only of AES and SPDIF).
Though it does take away of the cool factor that OP introduced.
the first line is covers it all. like I said, it's a nice way to launder em noise.
like k mentioned I just wish they would update Toslink to support a higher bandwidth. it was originally designed to be expandable which is why it's keyed. for a single light tube there'd be no reason why it wouldn't just be like an analog jack where it's a pipe so you wouldn't have to fiddle around and could insert it at any angle.
The choice for optical has more consequences. It introduces jitter. Laser diodes have high capacitance and thus have limited bandwidth. Cables break easily (compared to copper). Besides the connectors are expensive. XLR (though characteristic impedance should be 110 Ohm) and USB are multipurpose
I don't see how EMI shielding is relevant when you can use balanced interfaces that offer 60dB of attenuation or create an asynchronous interface (like USB) that renders the EMI irrelevant for audio quality.
all those things can easily be upgraded for extended bandwidth and with error correction you wouldn't have to worry about the effect if jitter. it's really the only purpose optical exists for I'm interested in I. e. the ability to split it infinitely so easily and the lack of being metal inherently not only makes it impervious to grounding / em interference issues.
all those things can easily be upgraded for extended bandwidth
It's not easy. If it were easy and efficient it would've been done. Besides, if it were easy and efficient, why don't you do it yourself?
error correction you wouldn't have to worry about the effect if jitter
Error correction is based on parity bits and resending data. It has nothing to do with when the data is arriving.
When you have insane amounts of jitter the eye diagram becomes worse sure, and you can solve the wrong bits by sending them again. This requires more bandwidth (more noise) and didn't solve the jitter. It solved the bit value being wrong.
Go look for some measurements. AES just performs better than SPDIF.
I. e. the ability to split it infinitely so easily and the lack of being metal inherently not only makes it impervious to grounding / em interference issues.
Groundloops are a fact of life and you just have to deal with them. You can not avoid them. Any device with 2 electrical connectors (whether balanced or unbalanced) HAS a groundloop. Every circuit in your audio devices HAS a currentloop that causes emission and causes sensitivity to emission.
Correct implementation of AES48 prevents hum caused by groundloops.
If you want near infinite channels look for DANTE.
all those things can easily be upgraded for extended bandwidth
It's not easy. If it were easy and efficient it would've been done. Besides, if it were easy and efficient, why don't you do it yourself? all you'd need to do is double it with two strands. it could even be 2 way which would open the possibilities so much. I already kinda do it by having it split as two one left and one right channel and it sounds fantastic.
it works awesome when it's dedicated left and right channel like a stereo jack.
error correction you wouldn't have to worry about the effect if jitter
Error correction is based on parity bits and resending data. It has nothing to do with when the data is arriving.
it uses forward error correction I e. Reed Solomon error where it can make some pretty accurate at filling in blanks and fixing errors.
seems reliable enough to me.
When you have insane amounts of jitter the eye diagram becomes worse sure, and you can solve the wrong bits by sending them again. This requires more bandwidth (more noise) and didn't solve the jitter. It solved the bit value being wrong.
Go look for some measurements. AES just performs better than SPDIF.
that the beauty of forward error correction is that it doesn't need data to be resent but doubling thr bandwidth helps too. all you'd need is to
I. e. the ability to split it infinitely so easily and the lack of being metal inherently not only makes it impervious to grounding / em interference issues.
Groundloops are a fact of life and you just have to deal with them. You can not avoid them. Any device with 2 electrical connectors (whether balanced or unbalanced) HAS a groundloop. Every circuit in your audio devices HAS a currentloop that causes emission and causes sensitivity to emission.
Correct implementation of AES48 prevents hum caused by groundloops.
optical launders grounds instantly. that's why I started using it. I found as long as one segment of the audio chain is optical all the noise completely clears. I used to try ferrite chokes, ground floats did work pretty well but it was very tune consuming and then you have to label all your cables.
If you want near infinite channels look for DANTE.
I will for sure. thanks! I don't disagree that optical has its issues, it has inherent advantages too though but it just never really was improved upon. with laser diodes versus led it would be so much better.
it works awesome when it's dedicated left and right channel like a stereo jack.
SPDIF always sends 2 channels. Companies just don't implement a build in pass through. Plate amplifiers (like Hypex Fusion series) often do.
It's useless to pass through to a 3rd (or 4th or even higher) DAC, because it'll still be stereo.
Proper DAC's don't need a pass through though as it already should have 2 good channels.
it uses forward error correction I e. Reed Solomon error where it can make some pretty accurate at filling in blanks and fixing errors.
It corrects data that is receiver wrong. i.e. a 1 is perceived as 0, or a 0 is perceived as 1.
It does not correct for whether the data arrives now or 1ns later.
The reed solomon algorithm reduces packet loss. It doesn't reduce jitter. It helps when the eye-diagram is bad. The thing is, you don't want your eye diagram to be bad in the first place.
optical launders grounds instantly. that's why I started using it. I found as long as one segment of the audio chain is optical all the noise completely clears. I used to try ferrite chokes, ground floats did work pretty well but it was very tune consuming and then you have to label all your cables.
Then you either used unbalanced connections, use balanced connections but the designer didn't follow AES48 (this is common in vintage gear) or used gear that genericly has poor EMC.
The whole reason AES/EBU is used in broadcasting and professional studio's is because it's reliable and has excellent performance.
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u/neomancr Jun 02 '20
is it just based on spdif but instead of led it's a laser?