Lossy codecs/mp3 aside, it seems like you are implying that Roon cannot be trusted to send bit perfect data, even when dsp is off, depending upon OS platform. That’s a fairly bold statement imo and there is no evidence of such.
What I do know is that I tested the input to HQP of a Flac file from Roon Server on a Mac and it was bit perfect compared to a stream sent directly via JPlay. Maybe Roon’s use of ffmpeg on Linux is not correct. Who knows. But this can also be validated easily enough.
Yeah, you can always do that on the platform you are running Roon on. (for example whether the FLAC version used is a one that can decode 32-bit or just 24-bit)
So there is no perceived difference in sound between Roon and JPlay when played to HQP possible?
From Roon I was trying to think about some potential differences in some cases, as I outlined above. Since it is overall rather different case. But not between JPlay and Client for example.
I’ve just installed Jplay IOs (demo version) in conjunction with HQP Desktop 5.10. I’ve installed MiniServer on my Synology NAS. I’ve started listening to some comparisons with Roon / HQP. My first impressions (to be confirmed) show a little more detail / transparency and above all a better holographic scene (I can distinguish the placement of instruments, voices…), perhaps a little less material.I don’t know if some of you have already been able to make this comparison, and if so, have you experienced these same impressions? Once again, this remains to be confirmed with a lot more listening.
100% mirror your thoughts!!! Definitely a cleaner, more detailed sounding compared to roon. Whether this is better or worse obviously depends on the rest of the system…
I am quite happy that even adding quite a bit more sub bass the mids are still quite clean
Do you have an explanation for this perceived differences? When JPlay and Roon send bit perfect data to HQP there shouldn’t be any.
Nope, none. It remains one of the mystery in digital audio to me and I am normally one of those folks that don’t easily believe in things like that…
Same thing. No clear explanation! Perhaps a difference linked to the RAAT and UpNp exchange protocol? but not sure… In short, only the listens and our ears are the judges 
RAAT is not in use between Roon and HQP.
It’s somewhere else then 
Guys, if i am in the know of what roon did to make the sound different than jplay iOS I would have written a letter to advise them don’t do it!!
Something strange happened when I turned off all offloads on the network card, so about 0.5ghz of processor usage disappeared, 2-3gb of memory usage and GPU usage went up to full. And then there was a change in the way that I think the sound is better after this! I can’t explain it but try it and see if you agree or if I’m just imagining it…
super 512+ psgl with dc and dsd512 / Roon
And cpu usage was 4.5ghz before shot
edit. I have Intel i226-v 2.5gb and QNAP 2.5gb switch
edit3. Maybe this is just happening on my computer if others aren’t experiencing anything similar… All drivers are up to date.
Those are my experiences as well. With JPlay, it definitely sounds clearer. The soundstage is wider. With Roon, the sound is somehow a bit more reserved but deeper. It’s hard to explain. I definitely think there’s a difference. However, I can’t really say which one I prefer. To me, JPlay and HQPClient sound identical, only Roon sounds different.
BShaw described it over at Head-Fi exactly as I feel it, or rather hear it!
My big takeaways from listening to JPlay are a first off, more refined soundstage - wider, taller, deeper, with instruments more separated and clear. There’s more sparkle in the highs, but not brightness. Imaging is notably more crisp. The presentation is more spacious and 3 dimensional.
See original post:
I’ve spent several hours listening to JPlay IOs with HQP (SDM256) both on headphones and speakers, and I always come to the conclusion that the experience is superior to Roon / HQP.
Transparency, clarity, sound image, in short nothing but positive.
I added a little more bass and it’s perfect, much more foot tapping I installed Jplay on an Ipad and Iphone which are not the latest generation, so I have a little latency but nothing serious.
It’s true that the library management isn’t as rich as Roon’s, but it’s still acceptable. What’s more, the look is very similar!
I read that you could install on Mac OS (I have a mini M2), but on the description of the program on Apple Store, it specifies IPad and IPhone and not adapted MacOS!
Question : is it a problem or not to install it on Mac OS?
Another question : if it were possible, Jplay would be on the same Mac Mini as HQP Desktop, bearing in mind that I have a Linux NUC for NAA which is connected via USB to a Cyan2 DAC, would that be better or worse than letting Jplay run on Ipad/Iphone?
Jplay is purely a UPnP controller app no benefit for it to be on the pc it’s designed to send comms from a UPnP server to send local music or a url for Qobuz or Tidal to the renderer to play. Nothing touches the app. It just instructs the server and player as to what to do. Roon does exactly the same in a HQplayer environment but without the added UPnP server.
Jussi can comment further on this, but the jplay hqplayer integration has very little if any to do with upnp.
Jplay has native support for hqplayer, controlling the hqplayer api
Yes, it may seem odd on the technical side.
But how do you explain the difference when you listen to it?
By remaining objective, of course
Volume levels matched??
I believe a 0.2dB is enough to bias one or the other to sounding different.
I to have believed I hear a difference between JPlay and Roon. JPlay sounded better, but it also sounded a little louder. If I turned up Roon a little bit more than JPlay, Roon sounded a little bit better.
But I am not saying there is not an audible difference, just that other factors come into play.
I’ve given up on the “This sounds better than Roon etc, etc”. I just listen to music I like in whatever way seems the best at the time. I flick between Roon, PlexAmp, WiiM Home App direct from Qobuz. Qobuz via Google Cast.
Curve ball, which OS sounds best 
