Article: The Sonos Port Isn't Bit Perfect

[schoondoggy]

I would guess that 90% of the installed base of Connect and Port devices are only connected using the analog inputs and/or analog outputs. Another way you may want to test the Port would be to factory reset it and added it to your S1 system and run the tests again. It would be interesting to see if the Port behaves differently on the S1 system.

[bunno77]

How large was the sound difference? 

[miguelito]

On 3/12/2021 at 10:19 AM, The Computer Audiophile said:

No. 

 

HDCDs played bit perfectly by any digital output into an HDCD DAC, will light up the HDCD indicator. It's the same for DTS signals. If the component can pass bit perfect signals, the DTS component will see it and indicate it's DTS.

In fact, I have a bunch of HDCDs that I ripped originally to 16/44 as if it were standard CD (I had no means of decoding HDCD). You can now run ffmpeg to decode those files into 24/44 files. 

 

Instructions for mac:

 

Files must be FLAC, not WAV or AIFF. <Album> is the directory where you have your original files. It assumes the ffmpeg binary is in the directory above and assumes that directory also includes an outfiles directory. 

 

At the command prompt do:

% cd <Album>  

% for f in *.flac; do ../ffmpeg -i “$f” -af hdcd “../outfiles/$f"; done

 

This will transcode all HDCD 16/44 files into 24/44 files. The output will tell you if the files were HDCD encoded or not. Metadata is preserved.

[scobihughes]

does anyone know if the sonos amp is bit perfect?

[The Computer Audiophile]

17 minutes ago, scobihughes said:

does anyone know if the sonos amp is bit perfect?

Impossible to test because it only has analog output. 

[Musiq]

I’ve juste finished to make a few tests as I have both connect and port on board still for a few weeks until the connect will extinguish itself :) 

 

speaking about processing, there is no doubt that Sonos pass signal through its DSP in variable and fixed mode. By the way, even with the analog output you can hear it on high resolving systems. BUT, when you set the output to Pass Through… then you recover the Fixed output from the old Connect, even better. The DAC is I think better and you can hear it with a good preamp/integrated amplifier and interconnects. Details and sound stages even if they are not as good as high end dac are convincing from my point of view regarding a wam sound signature at the opposite from SABRE Delta-Sigma constructions. Connect was not analytical as well, Port is in the same sound signature, but with better silence and less boomy low end.

 

I did not test the digital output yet, but as it is stated it will not process anything greater than 24/48. This is Sonos choice since years. 

 

despite that I like the client, the interface, the easiness to send flow of audio to multiple place in the house. the airplay 2 coupling works perfectly and without any delay from any source (iphone, ipad).

 

upnp works also smoothly, integrating sonos into an openhome network with bubbleupnp or with room. Sonos can stream external flow, but with a slightly different sound signature depending on the sources I have tested (minim, room, qnap upnp). the internal streaming mechanism seems to be sensitive to this kind of jitter.

 

This was my 5 cent on this topic, but, please make your tests in pass through mode (see S2 settings) to avoid going through the DSP and try to reverse powerplug because there is a HUGE difference there too (set phase on the upper pin, not the one close to the cable)

 

[The Computer Audiophile]

1 hour ago, Musiq said:

I’ve juste finished to make a few tests as I have both connect and port on board still for a few weeks until the connect will extinguish itself :) 

 

speaking about processing, there is no doubt that Sonos pass signal through its DSP in variable and fixed mode. By the way, even with the analog output you can hear it on high resolving systems. BUT, when you set the output to Pass Through… then you recover the Fixed output from the old Connect, even better. The DAC is I think better and you can hear it with a good preamp/integrated amplifier and interconnects. Details and sound stages even if they are not as good as high end dac are convincing from my point of view regarding a wam sound signature at the opposite from SABRE Delta-Sigma constructions. Connect was not analytical as well, Port is in the same sound signature, but with better silence and less boomy low end.

 

I did not test the digital output yet, but as it is stated it will not process anything greater than 24/48. This is Sonos choice since years. 

 

despite that I like the client, the interface, the easiness to send flow of audio to multiple place in the house. the airplay 2 coupling works perfectly and without any delay from any source (iphone, ipad).

 

upnp works also smoothly, integrating sonos into an openhome network with bubbleupnp or with room. Sonos can stream external flow, but with a slightly different sound signature depending on the sources I have tested (minim, room, qnap upnp). the internal streaming mechanism seems to be sensitive to this kind of jitter.

 

This was my 5 cent on this topic, but, please make your tests in pass through mode (see S2 settings) to avoid going through the DSP and try to reverse powerplug because there is a HUGE difference there too (set phase on the upper pin, not the one close to the cable)

 

I tried every mode available. 

[MgP2804]

Did ask in Sonos forum and had a chat with Sonos support on that. Pls. take a look here: https://en.community.sonos.com/setting-up-sonos-228990/sonos-port-connect-gen-2-spdif-max-samplerate-and-bitrate-6865790?postid=16582736#post16582736

[The Computer Audiophile]

2 minutes ago, MgP2804 said:

Did ask in Sonos forum and had a chat with Sonos support on that. Pls. take a look here: https://en.community.sonos.com/setting-up-sonos-228990/sonos-port-connect-gen-2-spdif-max-samplerate-and-bitrate-6865790?postid=16582736#post16582736

I don’t believe that’s correct. I did the objective tests. 

[Claudius2k]

So you're saying it downsamples 48K source sampling to 44.1Kz, ok but my concern more importantly is what about 24k bit depth? Is it chopped off at 16?

[MgP2804]

1 hour ago, Claudius2k said:

So you're saying it downsamples 48K source sampling to 44.1Kz, ok but my concern more importantly is what about 24k bit depth? Is it chopped off at 16?

Another thread at Sonos community, from just one month ago 🤭https://en.community.sonos.com/setting-up-sonos-228990/sonos-connect-port-and-digital-output-6864737

[The Computer Audiophile]

3 minutes ago, MgP2804 said:

Another thread at Sonos community, from just one month ago 🤭https://en.community.sonos.com/setting-up-sonos-228990/sonos-connect-port-and-digital-output-6864737

I’ve done the tests. No matter who comments on the Sonos forum about how things should work, I have objective proof they don’t work that way. 

[MgP2804]

2 minutes ago, The Computer Audiophile said:

I’ve done the tests. No matter who comments on the Sonos forum about how things should work, I have objective proof they don’t work that way. 

That other thread from just a month ago  confirms your measurements.

[The Computer Audiophile]

Just now, MgP2804 said:

That other thread from just a month ago  confirms your measurements.

Ah. I read it quickly and though it was another, “here’s how it works because it just does,,,” type of comment. 
 

Thanks for the follow up. 

[kayoti]

Hey, I'm having difficulty understanding some of this information.  Hopefully someone can help clarify, I'm connecting my turnable to an existing Sonos system.  Here is how it's set up:

 

Turntable > phono preamp > Five (line in),  playing on Five and grouped with other Sonos speakers in other rooms.

 

Turntable > phono preamp > Port, playing on Sonos speakers in other rooms.

 

-Will both of these setups yield the exact same result in audio?

-Will the DAC of the Port be used, even if I'm not using an analog out?

 

Thank you!

 

[The Computer Audiophile]

51 minutes ago, kayoti said:

Hey, I'm having difficulty understanding some of this information.  Hopefully someone can help clarify, I'm connecting my turnable to an existing Sonos system.  Here is how it's set up:

 

Turntable > phono preamp > Five (line in),  playing on Five and grouped with other Sonos speakers in other rooms.

 

Turntable > phono preamp > Port, playing on Sonos speakers in other rooms.

 

-Will both of these setups yield the exact same result in audio?

-Will the DAC of the Port be used, even if I'm not using an analog out?

 

Thank you!

 

The DAC in the Port is bypassed, but you are using the ADC in the port to convert analog to digital, before it’s sent to the Sonos speakers. 
 

For the most part, the sound will be the same in both configurations. There is a double conversion happening, from Analog (turntable) to digital (in the Sonos for sending/receiving and digital signal processing / volume control) and back to analog (output from the speaker).

[Parsnip]

Hi - I just came across this discussion. 

 

In the tests, you "setup both the Connect and the Port identically. Both units were set "Fixed" Line-Out Level."

 

On my Port, I also have a setting called "Pass-Through" which is in addition to the Variable and Fixed settings. Have you tested the Pass-Through setting to see if it makes a difference?

 

Thanks

[The Computer Audiophile]

35 minutes ago, Parsnip said:

Hi - I just came across this discussion. 

 

In the tests, you "setup both the Connect and the Port identically. Both units were set "Fixed" Line-Out Level."

 

On my Port, I also have a setting called "Pass-Through" which is in addition to the Variable and Fixed settings. Have you tested the Pass-Through setting to see if it makes a difference?

 

Thanks

Yeah, I tested that without a difference.

[Parsnip]

Thanks. I wonder what that setting is for then. 

 

I have a Port and I'm wondering whether to get an external dac. Is it worth it? 

 

I dunno. 

[Bevok]

I'm wondering if you still have the Sonos Port and have had the opportunity to retest recently? Sonos works with Apple Music and so many other services so just ticks the boxes for me - bit perfect isn't a deal breaker but would be great to confirm if it is still fiddling with the data.

 

Thanks

 

Bevan

[Parsnip]

3 hours ago, Bevok said:

I'm wondering if you still have the Sonos Port and have had the opportunity to retest recently? Sonos works with Apple Music and so many other services so just ticks the boxes for me - bit perfect isn't a deal breaker but would be great to confirm if it is still fiddling with the data.

 

Thanks

 

Bevan

Not sure if you are asking me, but yes, I still have mine.

 

I bought a Rega Elexa mk4 amp, which contains an integrated dac, so I am running the Port into that. The Rega dac  does sound a little better that the Port's one.

 

Personally, my advice would be to go and test your preferred set up or range of set ups in a shop if you can, and if you like the sound of it, make purchase on that rather than a on some theoretical data fiddle. 

 

If you are happy with the sound, but it. 

 

But each to their own etc (usual disclaimer).