Is there REALLY a difference in sound quality between USB and SPDIF?

[Profoundsoup]

Is this really something to take into consideration? 

[xtasemusic]

It depends. USB doesnt transmit sounds. it transmits data. and spidif is digital, so technically, No differences. but what is the USB hooked up to ? 

[xtasemusic]

Ill give you an example , I have a USB pre-amp that has SPDIF out. So SPDIF is the output , and USB is the method the data of the audio is transmitted to the SPDIF output. The preamp also has XLR and 1/4 inch TRS out. ( Im using TRS ) all of these outputs are called balanced. The main advantage of SPDIF is that it can transmit surround. but once again this wouldnt be about USB VS SPDIF but SPDIF vs XLR vs 1/4 TRS.

[ShearMe]

USB supports higher bandwidth and bit depths, but it is doubtful you could actually hear a difference, and it would be difficult to measure for most music. Optical can be useful in breaking ground loops that USB sometimes permits, which can be heard as a lessening of background noise.

 

Otherwise, they are both digital which means there's no difference.

The main advantage of SPDIF is that it can transmit surround

Not quite correct - There are Dolby and DTS technologies which can compress surround channels into a format that will fit into S/PDIF's bandwidth.

USB can support surround formats easily, there's just not many devices on the market which output surround and connect via USB.

[EliasNM]

A few years back it mattered more but now USB seems to be king of the hill, nowadays you don't really have to find asynched USB for better audio performance. There is no real difference now.

[HumbleMobo]

Is this really something to take into consideration? 

You can't get Galvanic Isolation on USB and there is awful jitter.  But the serious SPDIF are usually exemplary in terms of quality, and if you want almost no jitter you need to clock the SPDIF with something like, correct me if I'm wrong, a CS2000 75ps chip.  You also wouldn't need a sound card because their coax actually prevents electrical interference from your PC

[HumbleMobo]

A few years back it mattered more but now USB seems to be king of the hill, nowadays you don't really have to find asynched USB for better audio performance. There is no real difference now.

Yep both are asynched by default

[xtasemusic]

USB supports higher bandwidth and bit depths, but it is doubtful you could actually hear a difference, and it would be difficult to measure for most music. Optical can be useful in breaking ground loops that USB sometimes permits, which can be heard as a lessening of background noise.

 

Otherwise, they are both digital which means there's no difference.

Not quite correct - There are Dolby and DTS technologies which can compress surround channels into a format that will fit into S/PDIF's bandwidth.

USB can support surround formats easily, there's just not many devices on the market which output surround and connect via USB.

exactly what i meant. and yes USB supports surround but the format isnt USB. after the USB there is another piece of hardware. USB is Universal BUS. SPDIF  is a type of Digital audio interconnect. Its just not a matter of USB vs SPDIF but SPDIF vs other Digital audio interconnect. you can go USB -- SPDIF , you cant go the other way. 

[EliasNM]

Yep both are asynched by default

I was referring to the existence of adaptive USB, iirc, vs asynched which is now standard pretty much. I may be confusing it with some other term that I know but don't remember.

[HumbleMobo]

Is this really something to take into consideration? 

Unless you're going pro, and you're doing serious audio applications it's not recommended.  It's an expensive investment and a luxury on that note!  They are both incredibly similar but unless you get into the pro audio world, and you use some serious applications and you get into the nitty gritty of specs like that, then SPDIF is not needed at all.

[HumbleMobo]

I was referring to the existence of adaptive USB, iirc, vs asynched which is now standard pretty much. I may be confusing it with some other term that I know but don't remember.

Ah, ok I gotcha mate!

[EliasNM]

exactly what i meant. and yes USB supports surround but the format isnt USB. after the USB there is another piece of hardware. USB is Universal BUS. SPDIF  is a type of Digital audio interconnect. Its just not a matter of USB vs SPDIF but SPDIF vs other Digital audio interconnect. you can go USB -- SPDIF , you cant go the other way. 

I think I know what you are trying to say but audio experts do compares these two all the time because they allow audio through them, the difference is the data transfers of each, and USB does come out on top allowing the higher sample rates and bits among other features.

[Profoundsoup]

Okay so this was a argument a few years ago but USB seems to be the standard and just as good now. Okayy boyyssss thanks

[EliasNM]

Okay so this was a argument a few years ago but USB seems to be the standard and just as good now. Okayy boyyssss thanks

Yeah USB is better than SPDIF in a few things but they will deliver similar performance only a few will spot.

[Stefan1024]

It depends, as allways.

The USB clock is not very stable and leads to lower sound quallity, if the internal clock of your active speaker / amplifier is based on the USB clock. However good amps have theyer own cristall oscillator and your fine.

 

For 2.0 SPDIF is fine, for more speakers you need USB because of the data rate.

[xtasemusic]

I think I know what you are trying to say but audio experts do compares these two all the time because they allow audio through them, the difference is the data transfers of each, and USB does come out on top allowing the higher sample rates and bits among other features.

what im trying to say is that spdif transmit an audio specific stream ( you could plug Spdif to an amplifier ). USB transmits data that has to then be converted to a different medium using other hardware, XLR ,1/4 inch 1/8th inch.. cant just take a usb cable and fork in the other end to an amplified speaker and expecting it to work. yes USB is better for futureproof.. ness ? but spdif can transmit 24bit at 48k which really .. at this point , wont make a difference today. But once again for versatility USB is king.

[xtasemusic]

It depends, as allways.

The USB clock is not very stable and leads to lower sound quallity, if the internal clock of your active speaker / amplifier is based on the USB clock. However good amps have theyer own cristall oscillator and your fine.

 

For 2.0 SPDIF is fine, for more speakers you need USB because of the data rate.

SPDIF can send 24 bit audio at 48k and goes up to 7.1 if they havent changed or modified the standart. Clock would affect SPDIF and not USB.

[Stefan1024]

SPDIF can send 24 bit audio at 48k and goes up to 7.1 if they havent changed or modified the standart. Clock would affect SPDIF and not USB.

If I'm not misinformed at 7.1 your sample rate and resolution is limitted. And there are some 192k / 32 bit freaks out there

I do run Nupros A200 (active speakrs) in 2.0 configuration, they are connected to one PC over SPDIF and to the other over USB. Personally I can't hear a difference.

 

And clock jitter affects both interfaces, but the SPDIF clock is usually more stable.

[ShearMe]

SPDIF can send 24 bit audio at 48k and goes up to 7.1 if they havent changed or modified the standart. Clock would affect SPDIF and not USB.

 

S/PDIF only supports stereo audio. For multichannel surround, DOlby and DTS formats have to use compressed audio.

[HumbleMobo]

I think I know what you are trying to say but audio experts do compares these two all the time because they allow audio through them, the difference is the data transfers of each, and USB does come out on top allowing the higher sample rates and bits among other features.

Without going into too much detail and too prove my abilities you live in Oakland Calif. your service provider is Sonic.net and your area code is 510. hmmm just waiting to pull up your latitude/longitude ;3

[SSL]

As always, implementation is everything.

 

Yawn, moving on.

[Lazmarr]

Is this really something to take into consideration? 

USB and SPDIF both transmit via digital signals. Both are practically the same. However the benefits of SPDIF, optical, connections are that they are much easier and cheaper to run over a longer distance.

[ShearMe]

USB and SPDIF both transmit via digital signals. Both are practically the same. However the benefits of SPDIF, optical, connections are that they are much easier and cheaper to run over a longer distance.

Dunno about cheaper...

[Eugene Yap]

USB and SPDIF both transmit via digital signals. Both are practically the same. However the benefits of SPDIF, optical, connections are that they are much easier and cheaper to run over a longer distance.

I wouldn't agree on easier part. Optical cables breaks easily at sharp turns. If the connection tip gets too deep of a scratch it would not work anymore.

And also usb repeaters are getting dirt cheap as well.

[Stagea]

SPDIF can send 24 bit audio at 48k and goes up to 7.1 if they havent changed or modified the standart. Clock would affect SPDIF and not USB.

 

Optical SPDIF can often send/receive 24-bit/192kHz (depending on the optical receiver used) for 2 channels in uncompressed PCM form. 24-bit/96kHz is more common because receivers capable of reliable 192kHz are limited in availability. There is nothing stopping makers from supporting higher sample rates as long as they get the right transmitter/receiver (optical cable is quite high bandwidth), but higher bit depths may be a problem without additional encoding/decoding.

 

For surround, compression is normally used for SPDIF connections. 5.1 can be at 96/24 (DTS 96/24), while 48/24 can span upto 15.1 (E-AC-3) as long as bitrate is kept in line (not much material or device support for this many channels though). E-AC-3 compression is very efficient and can work with as little as 32kbps per channel (48/24 uncompressed is 1152kbps per channel).