Either there is something wrong with your streaming setup or you are simply exhibiting the results of expectation bias.
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I think we have an opportunity here to celebrate something wonderful!
Imagination!
The key to all human progress, really. Someone imagines something that doesnât exist, then they figure out how to do it!
Wonderful! Imagine how it would be if the CPU is the SS Great Britain! Great thudding CPU cycles reverberating throughout the entire structure!
Yes! Excellent! A tractor-driven endpoint!
Yes! No doubt thatâs exactly what they might do! Though I hope they donât use this house sound.
Yes! Intelligent life! Maybe theyâre audiophiles! 
What an imagination!
Yes! Change the output device. Iâd like to try this one.
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Those of you that donât think there is room for improvement in Roonâs playback quality should try Euphony OS and choose Stylus as the playback software.
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I once extracted the data from a DAC and compared it with the original file. They are 100% identical. Where is there room for improvement? Please explain.
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My colleague explains to non-tech people what an API is by using the three-point hitch as an example. It works, because they want to learn about electronic interoperability. Wish I could have a simple method to say âdigital signals does not work the same way as your expensive turntableâ. Then again, some are not interested in new knowledge.
And how did you âextract the dataâ from the DAC, and what does it even mean? You canât extract the data after the DA conversion except by doing an AD conversion and then you wonât get the same bits back. And if you extract the data before the DA conversion then you just get back whatever you sent in.
But if we put that aside. There is more to how a DAC sounds than the bits, and I know based on our previous discussions that you have a hard time understanding this. The simplest to understand is jitter (google it): the transparency of the DAC is very much dependent on jitter (both from input and generated internally) while jitter is not even applicable to a file or âthe bitsâ.
JItter from external input is to some extent solved by asynchronous USB (and even better solved by i2s), but you also have clock jitter which all DACs have to a varying degree. And that depends on the oscillator used, which in turn is very dependent on a clean and steady power (i.e. noise sent into the DAC gives more clock jitter). Noise generated by the DAC itself also lowers the accuracy of the oscillator, which is where software comes into play. By using a good strategy of keeping the stream steady, with enough headroom for buffer underruns but not more, I imagine you can affect the noise the DAC generates internally.
Luckily we donât need to be bothered by all this, instead we can use our ears to tell us what sounds better. For example, I got very noticeable better sound when upgrading the 24Mhz clock in my streamer to a Crystek CCHD-575 but I donât think I can explain exactly why although I imagine it has similar reasons to why software can sound different despite being bit-perfect.
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File->Roon->Ethernet->DAC->File2 (before DA)
Compare File and File2
If identical how can Roon SQ be improved? That was the question you ignored?
And jitter is not possible in an ethernet connection using TCP. If it exists after the transport I donât want to discuss now. So again, how can Roon be improved SQ wise?
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That makes no sense at all so I am just going to ignore it (or do you have a special DAC that can write a file?). I am sure most software can handle bit-perfect data and I answered why the sound generated by the DAC can still sound different.
For example, Roon bridge and NAA donât sound the same even without any up-sampling or other processing by HQPlayer, using the same streamer and same digital music. Having said that, the difference isnât exactly huge, but its there.
Next youâre gonna be telling me that those $400 USB cables donât do anything! Stop with your facts.
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You donât get my point.
It is easy to record a file with a digital output. You can try it with a streming device or another computer at the end, donât need to be a DAC. The point is that Roon without any DSP didnât alter the original data and so cannot improved in terms of SQ.
Differences in DSP, DACs or any post processing are a different thing and can sound differently.
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Good for you. Try it, the trial is free, and hear it for yourself.
I likewise wish Roon would spend some time listening to how their product sounds relative to Squeezelite running on the same box. The differences are easy to hear on a good system. Let the difference you hear drive you to try to explain why.
I figure Iâm wasting my breath as others have asked the same thing. It would be nice though if you tried to delight all your customers - not just those who refuse to listen for differences themselves because their perfect knowledge of such things has assured them that there could not possibly be a difference.
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I can easily do this if you consider the âDACâ to be the whole device and not just a chip. Many decent multi-channel professional audio interfaces can perform digital loopback - ie route digital audio from and output channel to an input channel. Some present multiple device drivers (per channel pair for eg) to the host OS as well, so even a player working in exclusive mode cant block this. The audio interface will have a single clock generally, so you will capture the data exactly and not in a resampled form.
I have an RME UFX audio interface that is capable of digital loopback (30+ channel audio routing matrix and mixer too) so I can trivially capture it into a DAW and did this out of curiosity with Roon ages ago. Unsurprisingly - the data was identical to that extracted from a FLAC file which I verified using DSP in ableton live DAW via max/msp. The identity test was to simply null cancel (phase invert one and sum with the other) the two data streams and look for non-zero sample values.
If people are finding that different players sound different when in theory they are all claiming pass though, then maybe they are not all using the audio subsystem in the same way and allowing to host OS to do something horrible (like mixing followed by a bad dither for eg).
My RME UFX audio interface can do exactly this - stuff a USB drive into it and it can record a file to the USB drive - the audio source can be anything that you can get into it - from the USB host, or via its analog inputs or many digital inputs, or even internal sub-mix(es) of those. The reason - well it is designed to be able to also perform standalone multi-channel live session recording and even mixing with some basic fx. Of course it can do exact pass through too.
I can imagine there being many people on this forum with access to a similar capability (or even the same) audio interface given the number of audio professionals who seem to like Roon.
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I hope 1.8 cures my tinnitus and increases my portfolio return. Improving my gas mileage would be a bonus.
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I would settle for tinnitus cure.
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This whole thread just reinforces that there are a lot of people who donât like how bit perfect sounds.
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Its more of a pass-through though than âextracting the dateâ, but yes with loopback you can achieve something similar.
My point is that bit-perfect to a DAC does not necessarily mean the same sound out from the DAC. But donât take my word for it, lots of what I have said is verified here for example:
And even more here:
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I have also tested Roon/chain for bit perfect using RME ADI-2 DAC. Not as advanced as the RME UFX, but the test is simple: You play test files with the software you want to test, and the DAC says pass or not.
Roon passes everything but 32 bit (that is, my setup that I tested, to be clear). I have read HQPlayer passes that one too.
Every altering of the data makes the test fail of course. So yes, it is possible to test your chain.
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I totally agree. And Roon is still doing its job, as other software, as a bit-perfect transporter.
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Facts are just the worst! 
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