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fiber optic vs coax vs USB cable from computer/source to DAC .... which is better ?

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#1
i'm 57 and not a golden eared audiophile so for normal eared mortals is there much if any difference or reason to choose one over the others IF the hardware supports them ?
 

Blumlein 88

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#2
There likely is no difference. There are some exceptions like Schiit gear that is overly sensitive to the USB connection. Or HDMI which can be jitter prone.

USB has the advantage that the connection carries no clocking information. The data is assembled in a buffer then clocked out by a crystal close to the DAC itself. Such free running crystals inherently have the lowest jitter. Coax or Toslink are good enough the differences aren't audible in almost all cases.

So stop worrying and use whichever is convenient.
 

derp1n

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#3
Use whatever's most convenient.
 

Sal1950

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#4
Toslink optical carries no ground connection.
Sometimes helps in the removal of ground loop hum if that should be a problem.
Toslink is also sometimes limited to 24/96 if higher data rates is important to you.
Otherwise sound over all 3 should be identical.
 

JJB70

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#5
I'll admit to not having golden ears, but over the years I've played around with the various options purely out of curiosity and never identified any discernible differences in sound quality.
 

solderdude

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#6
Technically the TOSLINK is worst as it cannot do above 192kHz. Some DAC's even have trouble reaching 192kHz on TOSLINK.
The TOSLINK signal is a 1:1 optical 'copy' of the SPDIF signal.
The reason for this is the quite limited data bandwidth of TOSLINK.
This is not a problem with real fiber optics (Multimode and single mode) but those DACs are very rare and old.

Both SPDIF, AES/EBU (a balanced version of SPDIF) and USB can be a hit or near miss depending on the DAC's implementation of the used receivers and data handling.

In practice when not being an audiophool I agree with the stuff written above... grab what's most convenient and works glitch-free.
 

graz_lag

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#7
In any of the 3 options, try to keep the connection as short as possible and away from the power amplifier power cord ...
 

RayDunzl

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#8

solderdude

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#12
TOSLINK wiki:

Audio signal Digital audio bitstream. Originally limited to 48 kHz at 20 bits. Extended to support all modern formats (Depending on manufacture and specification)

Bitrate Originally 3.1 Mbit/s; now 125 Mbit/s

Don't have that hardware here, but, there you go.

Toshiba Data Sheet:

https://toshiba.semicon-storage.com/us/product/opto/toslink/detail.TOTX1701A(F).html
That link is only for the transmitter.. The TORX versions are the receivers and these are the limiting factors.
Most receivers top out at 10Mb/s some at 6Mb/s and some even at 500kb/s.
There is only 1 receiver that reaches 125Mb/s but has a minimum datarate and thus only suited for synchronous data transmission.
SPDIF is synchonous though.
The 10Mb/s and lower can do a-synchronous as well (from DC upwards) and is why it is so bandwidth limited and jittery.
It's duty cycle is amplitude dependent due to their slew rate.
The a-synchronous versions are used in audio TOSLINK connections.
192/24 = 9.2Mb/s

In the trade (I am in optronics = fibre-optic electronics for my daily job) we affectionately call these 1mm diameter plastic 'fibers' light sewers.
 
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Blumlein 88

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#13
Some of the newer torx for digital audio now reach 15 Mbps since about 2008. The 125 rated stuff is mostly duplex smi connecters.
 
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#14
thanks folks :) . if/when i get a new dac and amp i'll go USB so i can get the best performance even if i can't tell the difference . to me the whole point of upgrading is to get the best performance i can afford . the JDS atom for a C note looks to have WAY BETTER specs/performance than i could have hoped for . i got more patience than money but i can afford a c not or so every 2-3 months and probally not become single again , hahaha

but i get the feeling this forum is gonna cost me more $ than i was planning on and probably a few uncomfortable conversations with my better half !
 

Sal1950

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#15
thanks folks :) . if/when i get a new dac and amp i'll go USB so i can get the best performance even if i can't tell the difference . to me the whole point of upgrading is to get the best performance i can afford . the JDS atom for a C note looks to have WAY BETTER specs/performance than i could have hoped for . i got more patience than money but i can afford a c not or so every 2-3 months and probally not become single again , hahaha

but i get the feeling this forum is gonna cost me more $ than i was planning on and probably a few uncomfortable conversations with my better half !
This site should save you wheelbarrows full of money compared to the usual audiophool ones ;)
 

Wombat

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#16
For audio, signal processing is a technical 'doddle'. Any problems are due to poor design, construction and application. THERE ARE NO VALID EXCUSES!

Of course some people like what inferior products present. God help them as there is no consistency in their world.
shock_40_anim_gif.gif
 

solderdude

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#18
Some of the newer torx for digital audio now reach 15 Mbps since about 2008. The 125 rated stuff is mostly duplex smi connecters.
Yes indeed, some of them do reach 15Mb/s, most are still spec'd to 10Mb/s (acc. to the data sheets) and in this case it does not really change things as both 10MB/s and 15Mb/s can only 'do' 24/192 maximum. At least for a reliable data transfer the 15Mb/s may be less jittery/problematic.
 

bravomail

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#19
Optical SPDIF with rates not higher than 24/96. The reason - no electrical coupling, no humm, no buzz, no interference - just pure bits. :)
But as other ppl said, and if don't have optical - use what u have, USB, coaxial etc
i'm 57 and not a golden eared audiophile so for normal eared mortals is there much if any difference or reason to choose one over the others IF the hardware supports them ?
 
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#20
There is a fiber optic USB cable. Made by Corning.
The Corning optical USB 3.0 cable has a metal conductor wire. It does not have galvanic isolation.
Never tied one. They seem to die early. Not sure if is from hot plugging or temperature. The limit is 45C, which is 113 degrees F. Gets almost that hot here.
I do use the Corning Thunderbolt Optical cable. 20 GB/sec transmission. And there is no conductor. Full isolation,like streaming or TosLink.
Each plug is powered by the TB jack. Longest cable I see for sale is 60 meters. I use a 10 meter to allow having the computer across the room from the interface.
I THINK the 10 meter USB 3.0 cable is 109.00 with shipping. If you try one, a couple tips to extend live. Do not plug and unplug with devises powered. Also attach small heatsinks to plugs.
BTW, the Corning TB cable is an improvement over a 1/2 meter Apple TB cable. Suspect it is the galvanic isolation.
 
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