Study: Is I²S interface better for DACs than S/PDIF or USB?

[Jimbob54]

I stand with the crazy notion that numbers are more than measurements when it comes to audio. Some X Files is really going on here.

Care to expand on that? What numbers? What measurements? What devices?

 

[Rusty]

First post here but I've lurked my way around some. It's too bad this subject has gone a bit sideways in this thread as I'm interested in it.

I have a Sonore Signature Series Rendu (SSR) (not the newer optical input Rendu) that is Ethernet in and has both i²s and s/pdif out. It's available to you for measuring and subjective listening if you'd like. I did use it with a PS Audio DS dac and (subjectively) preferred the i²s input/output over the s/pdif.

Recently, I was at a meet up to compare some network bridge options and dacs on a very nice system. The digital side consisted of a JCAT bridge with usb out to a Berkeley Alpha usb>s/pdif converter.

At one point we were listening to a Aqua Acoustics Formula dac and noted our impressions. Then we replaced the JCat bridge with a Aqua LinQ network bridge which also has i²s and s/pdif outputs, and fed the Formula dac s/pdif. Sounded (subjectively) identical to the JCAT bridge/Alpha converter. Then we connected the LinQ to the Formula via Aqua's proprietary i²s connection and immediately heard a large step up in performance. Much more than I'd ever noted with the PS Audio/Sonore connections. As with many things digital, the differences were not in tone and timbre but in atmospherics. Larger, deeper soundstage and better separation of instruments. Less blur and more focused. Improved transparency. All very important to reproducing a realistic live acoustic event. I appreciate many don't listen for these differences however, or use headphones, and have no idea if they're measurable.

I'm assuming the Sonore SSR or the Aqua LinQ have not been measured or evaluated subjectivity for the i²s vs s/pdif comparison? Anyone else have similar or different experiences?

 

[audio2design]

Everything is measurable .... even placebo effect.

 

[Rinaldi Moreira]

Parece inútil para mim. Ultra inútil.

Já imaginei seu pensamento sobre o assunto, já que você ouve números e gráficos ao invés de música ...

 

[pedrob]

I can already imagine your thinking on the subject, since you hear numbers and graphs instead of music...

I like your thinking.

 

[Gradius]

Já imaginei seu pensamento sobre o assunto, já que você ouve números e gráficos ao invés de música ...

If you can hear the difference, then you aren't human anymore.

 

[pedrob]

Hearing is the key. Seeing results isn't particularly relevant.

 

[Jimbob54]

Hearing is the key. Seeing results isn't particularly relevant.

Not much point being here then, is there?

 

[pedrob]

Not much point being here then, is there?

If you mean it's a futile exercise, then perhaps you're right.

 

[Jimbob54]

If you mean it's a futile exercise, then perhaps you're right.

Its a measurement led review site. Amir's reviews wont tell you much if you ignore the measurements. And on electronics there literally is no listening commentary. Walking into someone's house and saying its built on foundations of straw isnt going to go well, is it?

 

[vco1]

This may have been touched upon before, but what's the use of having an I²S port on a DAC if there are hardly any (if any at all) devices with such an output? I have been looking for a streamer, or a Raspberry Pi HAT, but found basically nothing. And discussions of Pi's supporting I²S go back as far as 2018 or so. If not longer.

 

[pedrob]

I totally agree foundations are absolutely crucial and measurements go a long towards deciding what should be put on a short list for consideration. I've found a lot of fantastic information here that I just couldn't do myself.

 

[Jimbob54]

This may have been touched upon before, but what's the use of having an I²S port on a DAC if there are hardly any (if any at all) devices with such an output? I have been looking for a streamer, or a Raspberry Pi HAT, but found basically nothing. And discussions of Pi's supporting I²S go back as far as 2018 or so. If not longer.

Add a feature, talk up the merits of that feature over the existing standard and produce both the sending and receiving devices with the feature.

Double bubble!

 

[Jimster480]

Add a feature, talk up the merits of that feature over the existing standard and produce both the sending and receiving devices with the feature.

Double bubble!

Basically this. I2S isn't even an open standard, meaning that 2 devices from different mfg's with I2S ports are not even necessarily compatible.

 

[audio2design]

Hearing is the key. Seeing results isn't particularly relevant.

Listening is key ... Controlled listening that is. We "hear" things all the time that aren't there. If you don't know or accept the importance of controlled listening then by definition you accept your own delusions.

 

[mansr]

Basically this. I2S isn't even an open standard, meaning that 2 devices from different mfg's with I2S ports are not even necessarily compatible.

I2S is an open spec for communication between ICs within a device. It was never intended for communication between separate boxes and thus does not specify a connector.

 

[sarumbear]

I think this should go in the conclusions, not everyone reads all the posts. This seems really important especially for those using old dacs with no GPLL, and can diy I2S.

Not everyone reads the post!!!

Why in hell they are opening a post about technical review post???

This type of logic beggars belief!

I run out of exclamation marks.

 

[sarumbear]

I2S is an open spec for communication between ICs within a device.

But not a standard. Nobody got together to agree on it. Philips wrote the specs, manufactured the chips, published data sheets & example designs for their customers to use them on their TVs.

 

[mansr]

But not a standard. Nobody got together to agree on it. Philips wrote the specs, manufactured the chips, published data sheets & example designs for their customers to use them on their TVs.

It's not a standard published by the IEC, IEEE, or similar organisation. It's still open and the de facto standard for interconnecting audio ICs.

 

[Victor BR]

Actually the only advantage of I2S and USB over SPDIF is the ability to carry DSD native and higher PCM resolution than 24/192.

I2S also allows carrying clock signal apart.