Question

Connect no longer bit-perfect?


It looks like the Connect is no longer bit-perfect. Here's my evidence: let's discuss this.

First, I constructed a wav file of pink noise with amplitude ramping up from zero to digital max and back to zero.
I play this through my Connect and record the SPDIF output from the coax output into my PC.
The recording uses a Scarlett 8i6 audio interface set to use the Connect as master clock.
I record into a DAW (Sonar) multiple times - all instances are identical.
However, this recorded signal is not quite the same as the original wav file - it can be up to -21dB different.
See https://www.dropbox.com/s/t8od479xo9hi5el/connect_diff.PNG?dl=1
Note the expanded scale on the difference (third) track.

It looks like the difference gets larger when the signal is larger. To confirm this, I import the
original and difference files into Matlab and plot the raw data (difference vs original). There is clearly audio compression
happening here. See https://www.dropbox.com/s/p1yq6wcqafvnhaj/diff_vs_orig.png?dl=1
The scale is such that digital maximum is 1.

There also appears to be a slight bias when the waveform is negative and the signal is below the
compression threshold. See an expanded version of the previous plot
https://www.dropbox.com/s/9001tl9mkle4wly/diff_vs_orig_zoom.png?dl=1

Happy to answer questions about the method and conclusions.

Cheers, Peter.

p.s. Volume is set to fixed - I haven't tried variable.
In a loopback test (8i6 out from DAW to 8i6 in, no Sonos gear involved), I get bit-perfect cancellation.

This topic has been closed for further comments. You can use the search bar to find a similar topic, or create a new one by clicking Create Topic at the top of the page.

453 replies

Userlevel 2
Badge +1
Jgaite

And I like you I want to make Sonos better than what it is today. I agree with you in on MQA. I personally would like to get batter mastered audio files streaming to our Sonos gear at a reasonable price. How ever that can happen is what I seek.

I do not know your history with Bluesound but obviously you must have a long history with them to be so passionate.

My personal quest for better sounding music involves many components: Sonos, other audio products and different sources of music (both purchased and 3 streaming services)

It is because of the streaming services that I really enjoy the Sonos interface. It is the best I and I would like it to stay that way.

Although my Sonos connect is ok on it own feeding some of my other equipment the sound was definitely improved by feeding an alternative Dac.

I have 2 connects feeding 2 Schiit Yggdrasil DACs and then onto other equipment and speakers.

The improvement in sound quality with the Schiit DACs Was quite apparent and worth every penny to me.

I have Sonos equipment and speakers running in 7 rooms in my house so keeping within the Sonos environment is very important to me.

My mentioning of Bluesound equipment it to draw attention what other competitors are doing in there quest to unseat Sonos.

I personally want Sonos to use us the Sonos Community as a resource. To take suggestions and help make their future products better.

Things are changing so fast these days that everyone including Sonos must do there best to stay ahead. The play 1 and the new play 5 were a nice addition to the Sonos lineup.

In my opinion they also need to refresh the Connect and Connect Amp. Yes these possible refreshed devices may share some of the features of their competitors and that is a good thing.

We are all guessing why there is a MIC in the new Play5. My hope is it will interface with Echo in the near future. Maybe a future Connect might have a similar MIC.

A 12v trigger, a new MIC. It does not matter Any improvements to me are great as long as we keep moving forward. Let's not stick our heads in the sand.

New enhancements can't just be software related. It must also include new equipment. I am a realist to know I will have to replace my connects just like I replaced my original Play5's. the original hardware is too old to support all the future enhancements Sonos has in store.

I would just like Sonos to acknowledge our attempts in trying to make them a better Company. I would like them to provide feed back on why some of my ideas may not fall within their future plans.

That ego stroking you refer to is not to benefit me. It is meant to benefit Sonos.

We only need there participation
I use Dot with a Wemo to power a vintage receiver via voice. 12V triggers are a bit old school.
Userlevel 2
Badge +1
Hi Chicks

I personally use a dot and a Harmony hub for similar task. I will agree to differ with you on the 12v trigger being old school. Most high end audio amps,preamps and Receivers have 12v triggers. My Audio visual processor has 2 -12v triggers that I find very important to me. Depending on the source I may only want 1 amp to come on(2 channel music) while on another source I want all 3 of my amps to come on for Movies etc.

Anyways it is fun figuring out different ways to make things automated the way we like it. The more features just allow us an easier path to the end game. 🙂
Sonos must do there best to stay ahead. The play 1 and the new play 5 were a nice addition to the Sonos lineup.

In my opinion they also need to refresh the Connect and Connect Amp.

I would like them to provide feed back on why some of my ideas may not fall within their future plans.

As to the first statement, Sonos sees it future markets for home audio moving in the direction of adopting the play unit kind of technology and I see no sound quality reasons - pardon the pun - as to why this is not a good thing. Given that state of affairs, it is quite obvious that devices like the existing Connect, that are meant for interfacing with legacy - and IMO now obsolete kit - is no longer a market of interest to them. These are choices that every company makes, given that resources are always in short supply. Those on the wrong side of the choice have to either decide to move forward with Sonos in the new direction, or move away from Sonos to other solutions that meet their needs better. These areas are now almost certainly niche markets for Sonos, that don't fit into their strategic choices.

As to the last statement, sharing future plans is always walking a fine line. Sonos has said often enough what their future priorities are: Voice control, streaming services, and their speakers being used for home automation. One just needs to read between the lines as to the ideas that may not fall in line with their future plans; it isn't reasonable to expect them to say so for every new idea that bubbles up, although like any good company, they are probably keeping a tab on these.

But I agree that there could be more active Sonos participation here, though I suspect it is another symptom of the scarce resources problem, and not arrogance.
No, the ego stroking is for you. Case in point; how big of an ego do you have to have in order to think you as a layman know what Sonos can do to make themselves better, and lord stars, those ideas just happen to coincide with your personal wants? And you are personally e-mailing the CEO to tell him? It's like the return of wappinghigh.

Besides, if Bluesound is so superior in products and culture, you'd think you'd have switched to their product by now.
I keep hearing about Bluesound, I just looked at it on Amazon and found a total of 2 reviews for all their products - one a 4 star, another 2. Just one data point, I know, but compare that to the thousands of reviews for Sonos products, most of them 4/5 star. I don't believe that Bluesound does anything audible that Sonos cannot do for a lower average price point. And it does not do what Sonos can, that is essential for stable streaming around the home - the SonosNet mesh trick.
Userlevel 2
Badge +1
Jgaite have a great day.LOL

Kumar

I am not sure about the the Bluesound performance myself. I hear that there were definite problems with their software interface. I am not sure if these issues have been corrected in there latest software. I just like the the hardware features they are offering. If I was to critique their hardware I would like to see a USB digital out added to the node 2.

I am curious to know if I could tell the difference is sound quality between a Node 2 and a Connect. I would love to give it a try at my own house with my setups to see if bit perfect does make a difference in sound on my audio systems.. Unfortunately there are no stocking Bluesound dealers where I am.

I might order one in the future to give it a try. Of coarse I would Prefer Sonos to come out with a similar offering in an updated Connect to save me the money:)
Userlevel 2
Badge +1
Roon integration ( Roon version 1.3) just announced. Nice:)
Userlevel 2
Badge +1
Update:)

It may appears that Roon may have a solution. . From another forum "We do support lossless streaming up to the limits of the hardware, which are 48kHz/16bit audio."

Great news if true. You just have to use alternative software.
Userlevel 2
Badge +1
Sorry for the hope folks. Roon does not have any control over the hardware only what it sends to it.
To throw in my 2c...

I'm personally fairly disappointed with Sonos making this change without considering the impact on users, many of whom purchased the Connect precisely because it was bit-perfect. I understand, to an extent, why they did it (implementing such a compression scheme makes sense when volume normalisation is involved). However, doing so without maintaining what many would consider to be baseline functionality of the Connect in same way (such as a user option to disable) seems like a huge misstep.

I do hope they address this in a future update to avoid reputational damage.

I should add that, whilst I have a Connect in my collection of Sonos kit, it's currently not in use and is certainly not likely to be used in anything approaching an "audiophile" setup in the imminent future: that sort of tweaking and tinkering is in my past. So I'm not directly impacted by this, but I understand that others are.

Cheers,

Keith
As for Bluesound, I think it's important to note that Sonos started out in this way too: a predecessor to these forums was full of people interacting with Sonos staff, making suggestions. providing feedback, and getting direct responses from Sonos Product Engineering. Many of these discussions resulted in changes to the product and new features being added.

Once a company gets to a certain size, this sort of interaction is unmaintainable. Sonos has gone from a small start-up with a few thousand customers to one of the top-3 speaker vendors in the world, and probably the leader in whole-house streaming systems. Their customer base is now reported to be in the millions across the world. It's simply not possible for them to respond positively to every customer on every issue. For every customer who wants high-end enhancements, there are 100 who want Sonos to make a low-quality Bluetooth speaker, or wireless headphones, or a portable garden speaker, or the SUB in pink...

That Bluesound are able to engage in this sort of interaction points to them still being a small company with relatively few customers, just as Sonos were back in 2005. It points to them still being in the development phase of the product and the company. It points to them having a brand new platform without yet having to deal with legacy support/compatibility issues.

If they ever grow their market share to be any sort of real commercial threat to Sonos, then they will have to abandon this sort of consumer interaction.

The chances are they won't get that big and, in which case they can be a viable alternative to Sonos, catering to a niche of customers who want something over and above what Sonos does. Although that puts them and their customers in a very precarious position.

One way or another, in a few years time you are going to be unlikely to have the same sort of interaction with Bluesound staff as you are currently seeing.

Cheers,

Keith


The chances are they won't get that big and, in which case they can be a viable alternative to Sonos, catering to a niche of customers who want something over and above what Sonos does.

Couple of questions:
1. As to bits not being perfect - I don't really care since I don't hear the difference and I suspect that many that do, started doing so after this thread started. But I take your point about bits and what would have made a useful difference to me is availability of volume normalisation; has that really improved consequent to this change? I haven't found that to be the case either, unfortunately, but that maybe because what I am looking for is normalisation across mixed source playlists and that may be a different problem altogether.

2. Sonos went mainstream largely at the expense of Squeezebox, I imagine. Because, with Sonosnet, and less tinkering to set up/stabilise, it offered a better alternative to a large part of the user base, is my guess. Other than Hi Res, what does Bluesound do that Sonos does not? On the negatives, it does not offer mesh architecture, and costs a lot more.Expanding the question, is there anyone visible at this time that threatens the Sonos castle in home audio? Echo?
How do you know you don't hear a difference? You can't A/B between DSP on and off.
Lol. How do you know that you do?! 😃 All I know is that there is no change in how my music sounds playing in the Connect driven zone, singly or in a group. Did you find music sounding different and then investigated things or was it the other way around, having done the investigation as a "fun" project?

But I do know for sure that I have seen no changes in the normalisation situation. Normalisation within an album doesn't seem necessary to me because my jazz is well recorded, but across albums and sources is when I have a problem playing shuffled mixed source playlists. Much more so with mixed source like NAS + Apple Music.

And another question: Is there anyone in the market doing this kind of normalisation effectively?
Userlevel 5
Badge +10

That Bluesound are able to engage in this sort of interaction points to them still being a small company with relatively few customers, just as Sonos were back in 2005. It points to them still being in the development phase of the product and the company. It points to them having a brand new platform without yet having to deal with legacy support/compatibility issues.

Keith


Not as small as you suggest. It is part of The Lenbrook Group, owner of The NAD Electronics and PSB Speakers brands.
I haven't said that I hear a difference related to the DSP. I initially heard a difference between the Connect digital and analog outputs through a new Peachtree amp that has both inputs. It was only when making measurements related to this that I discovered the Connect DSP problems. This DSP is applied to ALL Sonos units as far as I know, so you won't hear a difference between them related to this.

The Sonos compressor only affects volumes within 3.6dB of the maximum (greater than 66% of full scale), cutting out below this. The volume reduction ratio gradually increases above -3.6dB, and eventually becomes a brick wall, not letting any signal exceed 90% (-1dB less) of the original. It also has a zero attack and decay time. A brick wall compressor with no attack/decay ramp is a bit extreme. This may or may not be audible, but at the very least we should be able to disable it in fixed volume mode.

I'm totally with you on the normalisation issue.

Cheers, Peter.
It was only when making measurements related to this that I discovered the Connect DSP problems. This DSP is applied to ALL Sonos units as far as I know, so you won't hear a difference between them related to this.


I have the Connect in just one of five zones; the rest are play units/Connect Amp driven, where the bits are an internal matter to the units, irrelevant to the user and not measurable. Rightly so, IMO, because all that matters is - how does the music sound on its own and compared to that from other solutions out there? And here I find Sonos beyond Connect can still be as good as it gets to my ears, where rooms sizes aren't outliers, being so large as to need a lot more power/sound levels than what Sonos can deliver.

But perceived sound quality noticeably fluctuates with sound level differences which is why I think normalisation is very important in an environment where mixed source playlists are in use; my solution so far has been to not make/use such playlists. Neither Sonos or anyone else seems to think this is an issue, given the lack of any progress on this front. One day perhaps, once they are bored of devoting resources to controller cosmetic changes!

But perceived sound quality noticeably fluctuates with sound level differences which is why I think normalisation is more important in an environment where mixed source playlists are in use;


Totally agree - this is a bigger issue than any minor compression.


One day perhaps, once they are bored of devoting resources to controller cosmetic changes!


I wouldn't call the recent controller changes cosmetic - they degrade the user experience. I never know what I'm going to get when I click on a song. There are also a couple of ways of getting a nasty surprise. Occasionally I accidentally touch a song while scrolling and change the song inadvertently. Also, adding a song as 2nd in a stopped queue leads to a musical surprise at the end when the next song in the queue (left over from last night's rave party!) starts blasting.:D

I wouldn't call the recent controller changes cosmetic - they degrade the user experience.

Quite possible; I just learn to take things in my stride each time things change.

Here is the thing: once things are settled, even with some imperfections, cosmetic changes for no reason other than a change always run the risk of upsetting things that have worked well in the past. In trying to win over some preferences, others are lost. Stability would be far more useful to those that aren't easily bored; workarounds can then become habits for the little issues. But that isn't the way of the world in these areas now, constant churn seems to be the thing.

Couple of questions:
1. As to bits not being perfect - I don't really care since I don't hear the difference and I suspect that many that do, started doing so after this thread started. But I take your point about bits and what would have made a useful difference to me is availability of volume normalisation; has that really improved consequent to this change? I haven't found that to be the case either, unfortunately, but that maybe because what I am looking for is normalisation across mixed source playlists and that may be a different problem altogether.


My response was based on an understanding I got from other discussions in these forums, where it was suggested that Sonos now applies volume normalisation even when the Connect is in fixed-volume output mode.

https://en.community.sonos.com/setting-up-sonos-228990/volume-normalization-processed-fixed-volume-output-6738413

2. Sonos went mainstream largely at the expense of Squeezebox, I imagine. Because, with Sonosnet, and less tinkering to set up/stabilise, it offered a better alternative to a large part of the user base, is my guess. Other than Hi Res, what does Bluesound do that Sonos does not? On the negatives, it does not offer mesh architecture, and costs a lot more.Expanding the question, is there anyone visible at this time that threatens the Sonos castle in home audio? Echo?


Regarding Bluesound, they offer nothing that I want that I don't already have with Sonos, and I suspect that will be the case for the vast majority of people. As I suggested before, some may be drawn to the fact that they still seem to be in start-up/development mode and that will allow them to feedback and interact with the company more, but that is likely to be a temporary thing.

As to competitors, I actually think Google are the biggest threat to Sonos today. Amazon seem to be more advanced with their development and partnerships of their Alexa voice interface, but Google have casting/streaming of both audio and video, which Amazon do not, and (IMO) Google's media services are also better than Amazon's.

Cheers,

Keith

Not as small as you suggest. It is part of The Lenbrook Group, owner of The NAD Electronics and PSB Speakers brands.


That doesn't mean that Bluesound itself is a large company, or that they have a lot of customers.

It's a private company so information is difficult to find on it, but from some research it seems they have less than 30 employees and revenue of a few million dollars, which equates to less than 10,000 units sold. That is approximately where Sonos was as a company back in 2005.

Based on these figures, they are a company firmly in start-up mode.

Cheers,

Keith

My response was based on an understanding I got from other discussions in these forums, where it was suggested that Sonos now applies volume normalisation even when the Connect is in fixed-volume output mode.

https://en.community.sonos.com/setting-up-sonos-228990/volume-normalization-processed-fixed-volume-output-6738413

I know; but I haven't felt a great need for normalisation when I play any of my albums, one at a time, so I haven't also perceived any great effect of anything that Sonos may have done on this front from the time I have Sonos - August 2011.

Where I need normalisation and don't get it even now is if I am playing two albums, one of which is recorded louder than the other, in a shuffled playlist. Or when I shuffle play a list built from tracks from Apple Music and from my NAS; I find that sound levels obtained from Apple Music are lower than that from CDs ripped to my NAS, so here again mixed source playlists still have sound levels variances to the extent of being a distraction. Even today.

Does any one offer a solution with normalisation that addresses this issue? Sonos does not.

And I get what you said about Bluesound, thanks.


As to competitors, I actually think Google are the biggest threat to Sonos today. Amazon seem to be more advanced with their development and partnerships of their Alexa voice interface, but Google have casting/streaming of both audio and video, which Amazon do not, and (IMO) Google's media services are also better than Amazon's.

So I guess the trick Sonos has to pull off is of the kind they have with streaming services - of being agnostic to which service is being used.

One should be able to use Sonos with either Amazon/Alexa, or with Google/equivalent.
[quote=Kumar]
So I guess the trick Sonos has to pull off is of the kind they have with streaming services - of being agnostic to which service is being used.

One should be able to use Sonos with either Amazon/Alexa, or with Google/equivalent.


Agreed. I also think Sonos also need to consider extending the casting solution they implemented as part of the Google Play Music integration far wider, at least on Android devices, with the aim of achieving parity with Google Cast.

Cheers,

Keith