No, ROCK is a tailored thin Linux OS. Tailored to run on specific Intel NUC hardware with the sole purpose to run Roon Server (the same software you already use) on it. See also:
No. You may try to run it on other, potentially more powerful, hardware but your options may be limited here as drivers for other hardware than the one that comes with supported Intel NUCs are not included (tailor made).
What you are describing is what Roon Labs used to call āCoreā. I wish they had kept that terminology, since it was helpful in cases like this.
Reference: https://help.roonlabs.com/portal/en/kb/articles/what-happened-to-the-core
You can see why this is confusing since the term āRoon Serverā is now overloaded. It could refer to any system running Roon Server or just the Roon Server application itself. :-\
Iām glad to hear that you are making progress. I do wonder if the supposed benefits of HQPlayer are worth the inconvenience, power usage, fan noise, etc. What process have you followed to determine (objectively and subjectively) that your listening experience and engagement are significantly elevated vs using Roonās own DSP (or no DSP at all)?
From what i understand @Stefan_Jorma wants to optimize performance of a combined install of HQPlayer and RoonServer on the same PC running linux Ubuntu.
Thereās a misunderstanding regarding the RoonServer application inside ROCK being āthinnerā or more optimised than the regular Linux RoonServer application and therefore desirable to be āextractedā from the ROCK distribution to be used on a general purpose Linux installation. As pointed ou by others this is not the case, both RoonServer applications are the same.
I see the following options for @Stefan_Jorma here:
a). figure out a way to make the existing Ubuntu installation leaner to free up system resources, for example move from desktop to server version, if youāre running desktop.
take a look at this thread for advice regarding performance tweaks:
b). Seperate RoonServer and HQPlayer on separate machines. This way you could put RoonServer on a relatively inexpensive NUC running ROCK and enhance performance for both Roon and HQPlayer. This should free up significant resources for HQplayer on the existing PC.
c]. get an even more powerful machine to keep both Roon and HQPlayer on the same machine.
C) probably would be a better choice yet Iām an endpoint is needed to minimise and āisolateā the latency from the heavy workloaded powerful pc.
The NAA is already in place. Further equipped with a Matrix Audio, proprietary hifi USB controller card, 100% galvanically isolated from the NAA motherboard noise, and additionally fed from external linear PSU.
Futher I am thinking of a more powerful PC, but the input is high in money, as I have to start from the beginning with new chipset and CPU socket design, CPU, RAM. The graphics adapter is OK to move over. It will have to wait, I want to upgrade my HQP before upgrading the PC.
thnx, broā¦
Maybe youāll be interested in this Snakeoil OS (snakeoil-os.net) . I used for several years with mpd, before I use Roon in last August. Recent edition is installing a Ubuntu server 22.04 LTS (minimized installation). And then running their installer, then those unnecessary background process and gui will all be trimmed/disabled. One may further enhance the sound by replacing it with ubuntu its official lowlatency kernel, or even real time kernel (need to register , FOC if not more than 5 devices)
FYI, in this half year Iāve tried ROCK and installed Roonserver in that trimmed Ubuntu OS. In my system, Roon produces better sound with Ubuntu Real Time Kernel with Snakeoil OS than ROCK, the difference is quite obvious.
And even the endpoint, Raspberry Pi 4B, is also installing in the same way, ie installing RoonBridge on top of trimmed Ubuntu Server with Real Time kernel. Of course that produces better sound than other method I can try.
Yet it needs only some elementary linux knowledge to complete the installation. I believe youāve already learnt more than it needed.
No you need GNU Hurd because only microkernels sound really good 
Thnx for understanding my question <3
I got the intel I needed from you and @David_Snyder , the ROCK distribution is not to be considered to be leaner than Server SW. That changes the game and means that grabbing the ROCK and somehow install it on the Linux Ubuntu is of no additional value. Now I can park that thought in the infinte garage of thoughts trashā¦
The other suggestion, to move over to Ubuntu Server is a no go for me, as of yet. I am not a Linux guy in love with the terminal. I just barely learn enough to overcome the latest challange. I know that challanges the performance, but I have got into the Linux world with far less explicit expressions using the desktop version and occassionally having to use terminal, than going in āhotā using the terminal only. I know it is a matter of getting into stuff, but for a guy +60 (me) that started the PC life with a MAC (1988), later building my own PCās after starting with W95 and on (1991), it is a jump-start back using the prompt/terminal considered in my view to a level of computering at the 1980. I think already the HQP Embedded is work enough, however brilliant the SW.
It is one hell of a question, because it borders to a dogm; a matter of bitperfect, or mathematically washed bitstream. People get enemies on the internet discussing this. I was a proclaimer of the purest bit-perfect, before I tried the HQP. After which me, and all of my hifi-friends, concluded that music have never been as accessible (no matter production quality or source code) as with HQP. I am no maths guru. I do not understand how it works, but the impact on music both I and all of us understood immediately after a few seconds of playing. There is hardly any album or track that become harsch and sibilent anymore. Modern mix and masters, sound modern, but are pushed over to the more authentic instrument and voice sound side. You will in the total cacaphony (ie the product of the legendary Spectors wall of sound) of a contemporary pop hit, calm down the energy and make space between the notes, hence being able to actually listen to the arrangements. On old-school music, my cup of tea, the level of authenticity is unparallelled so far. I am guessing the benefits are when reestablishing the analogue signal. The noise vanishes. All the extra harmonics smearing the notes is removed. There is no bass hump remaining, also a result of over-energetic high-mid/top. There is nothing sounding in between the notes, that is so common. Several musicians, studio amangers and alike in my accuaintenceship have stated that it took a while for them to att all appreciate the digital media, as it did not sound equal to the real thing. Now I understand what they felt. I have a hard time to understand all the terminology among the hifi nerd society, but I guess the word is āorganicā. Meaning delusively authentic, you start to beleive this is really happening; it is carbon based devices behind the sound. In much digital/electronic music, this is lost in translation (IMHO). One of my best friends is a movie and music studio owner and a very good sound engineer, says if he is mixing and mastering, he would like the outcome sounding as good as at my place.
That is the subjective part. The objective is the measurings Jussi done, especially on the RME DAC I use. He measured the Audio Science Reviews measurements and gained dynamic range. However I would guess (without measurements) that it in fact increases the distortion if it is treated literally in masurement as it should, the sound is in fact nolonger the same as the source code, ie the master has been āre-masteredā in lack of other words.
It improves (but also alters) the code to the DAC chip, as do the DSP chip upsampling for the benefit from better filtering. Thanks to the DAC settings, I can bypass the onboard DSP chip, which is good if compared to a similar DAC at 40 bit depth upsampling, volume control and filtering, but is inferior to the HQP 64, 80 and 128 bit depth floating resampler of HQP magnitude. I have had the pleasure to listen to the Chord electronics MScaler and the exceptionally lavish MSB Digital Director, but that cannot cure the reference tracks I use for the harschest, most sibilent music. I often wonder if I am alone, am I hearing other stuff compared to others, but when they visit me they everyone state exactly the same; finally a high-end rig that does not slaughter poorly mastered music, but instead cleans it up to enjoy them for the music sake. Further they do not lack anything from the SQ when it come to high-end hifi recordings as one might assume the massiva bitstream re-calculations would alter good masters for the worse, but not that I or anyone else have ever claimed.
Just as a funny fact, Madonnas hit track Hung-Up sounds horrendous as is, wherever I listen to it, except at home. The over-energetic high-mid is dreadful. When done, the HQP apodizing filter of my personal choice (poly-sinc-gauss-xla) have made 10.000 real time corrective actions while playingā¦
Donāt know if this is enough answer, but the best I can give. 
I will for sure look into this! Thnx, bro
Another option for a āminimumOSā might be DietPi for native PC.
Haventāt tried it for myself on a PC, only on a Pi.
DietPi offers quite comfortable text based configuration utilities, so itās not purely command line.
RoonServer is available through the package installer utility as well.
HQPlayer Embedded should work on this, too. But as far as I understand, youāre running the desktop version, which is a different license tier AFAIK.
And this too, thnx bro ā¦ 
Debian 12 is another option, itās what runs my NUC, very efficiently and Debian is stable.