Connect no longer bit-perfect?

It is my understanding that DACs also need an analog filter (called a reconstruction filter) on their output. The conversion of discrete digital information into analog voltage 44100 times per second leaves a jagged signal, and this must be smoothed to provide a continuous voltage with no aliasing or supersonic artifacts. This filter has a tough job - it has to be steep enough to go from zero gain at 20kHz to something very low at 22.05kHz (less than -60dB?) Such a filter will potentially have phase problems. This is where oversampling can be very helpful. I don't know how Sonos implement this filter, or whether it is an integral part of the DAC chip.

I wonder where Sonos implement their brickwall limiter? Older Connects don't have it, but software versions prior to 6.0 don't either. So it would seem to need a mixture of hardware and software. If software can activate it, presumably it comes before the DAC, so it is in the digital domain. In which case, why is additional hardware needed?

I presume that the brickwall limiter applies to all Sonos units, not just the Connect. Does this mean it is just software? Or are older Play units immune to it because they lack the right hardware?

If you are a "high end" audio company, you can just leave the reconstruction filter out, lol.

http://www.stereophile.com/content/audio-note-cd-41x-cd-player-measurements

To his credit, technical reviewer Atkinson trashes it in his summary. The subjective reviewer, of course, gave it a rave review. Typical audiophile nonsense.

To his credit, technical reviewer Atkinson trashes it in his summary.
Does he? I am not so sure, these are his last words:
"does it sound good because of how it measures or despite it?" - not ruling out that it sounds good, is he?
This from a USD 12K bit of kit. Is this a digital version of the preference among some for distorted valve amp sound?

Typical audiophile nonsense.
I came across this today: "It's audiophile only if it's inconvenient". It seems to me one could also say: It's audiophile only if it causes anxiety. And It's High end only if it is expensive.

It is my understanding that DACs also need an analog filter (called a reconstruction filter) on their output.
There is normally a simple external RC analogue filter as part of the design of the output stages coming from the DAC. Most DACs will give a recommended design in their data sheet. There is the potential to mess the implementation of this filter up, but this sort of filter is well understood and is neither complex nor expensive to implement.

Cheers,

Keith

I wonder where Sonos implement their brickwall limiter? Older Connects don't have it, but software versions prior to 6.0 don't either. So it would seem to need a mixture of hardware and software. If software can activate it, presumably it comes before the DAC, so it is in the digital domain. In which case, why is additional hardware needed?

I presume that the brickwall limiter applies to all Sonos units, not just the Connect. Does this mean it is just software? Or are older Play units immune to it because they lack the right hardware?

I'm making educated guesses here. The brickwall sounds, to me, like it is implemented in the digital domain as part of the compression algorithm. In other words it's DSP based. This could be entirely software based (using the general purpose processor) or hardware accelerated (using dedicated audio DSP hardware). I suspect the latter.

In this case, the implementation later Connect units could point to better DSP capability which, given it is highly probable that the components used in various models of ZP80/ZP90/Connect have changed over the years, shouldn't be surprising.

Cheers,

Keith

In this case, the implementation later Connect units could point to better DSP capability which, given it is highly probable that the components used in various models of ZP80/ZP90/Connect have changed over the years, shouldn't be surprising.

So the question that comes now is... how do I tell which one mine is? Maybe we should all dig through the /support/review page and look at Connect details to see if we can find something to identify?

So the question that comes now is... how do I tell which one mine is? Maybe we should all dig through the /support/review page and look at Connect details to see if we can find something to identify?
No need. Look in About My Sonos System. Ryan said that this affected hardware version 1.16.5 or higher.

Well, I said I was finished with this, but I still own a Sonos product, a PlayBar, so as a customer I will chime in again.

This thread has gone way off subject. Here's the thing, I went to my Audio dealer and told the salesperson I wanted something that would transport my lossless 44.1/16 audio files iTunes or FLAC, which I was switching to and from Deezer or similar to my Peachtree amp without modification - bit perfect. I was directed to the Sonos Connect, which, at the time did just that. I was not interested in the Connect's analog output. I was having nightmares with Apple's Airport Express, having to reset it frequently, though it did transport the files bit perfect when it worked.

Now this is key - it doesn't matter if anyone thinks I should be happy with a Connect and a house full of Sonos speakers. It doesn't matter that the Connect has a good interface and can do global searches. That is not what I was sold, that is not what I had and most certainly not what I wanted and paid for.

The Connect worked fine for me until I moved in September 2015 and did not get my system reconnected until the end of 2015. It was in a smaller room with hard walls instead of the log walls of my house. I tried a lot of things to figure out why it didn't sound "right", quilt on the wall behind the sofa and more. Then I see Peter's post that started this thread. Seeing Sonos staff member Ryan's post saying he had submitted a ticket, I had hope. It never went anywhere.

I decided to try something else. I liked the idea of having the files stored on the transport device, so I tried the Auralic Aeries Mini with a 240GB SSD in it that I was not using. It was dramatic. Now "dramatic" is just my opinion, but that's my two cents. My system was back!

I called the audio dealer where I bough the Connect and they were stunned about the firmware changes made in late 2015. They were still selling and shipping them as bit perfect transports. They only carried Bluesound and I had some issues with it so bought the Aeries Mini from Audio Advisors. I told them about this thread and they too were surprised because they were selling them as always - bit perfect transports.

I don't think this hi res, MQA, Sonos speaker, audiophile thing is relavent to this discussion. Maybe Sonos didn't specify the Connects and its predecessors were bit perfect, but they were and dealers did sell them as such and still do. There is at least a breakdown in communication between Sonos and some of their dealers. To me it's almost as if Samsung updated my TV firmware and decided green pixels were no longer important.