by Maarten van Druten

ROON is an modular audio streamer software solution, that can be installed on many different ways and on different operating systems and devices.
I was curious about this software, so I wanted to know how ROON sounded, and how it worked.

I installed the headless solution of ROON; called "ROON SERVER"
This version wil be installed on my Intel NUC (mini computer)
For this test I will control ROON SERVER with an Android app on my phone and with my Apple MacBook Pro laptop.

First I installed Windows 10 Pro on my NUC, and then I installed ROON SERVER on it.
ROON SERVER is just an application, that provides a service that is running on the back ground.
My DAC is the Audio-Gd Master 7 with an Amanero Combo 384 module, so I also installed  the driver for it on the website of Audio-Gd:


For listening to music I used my PureAudioProject Trio 15 Voxativ open baffle loudspeakers.

Because the NUC is going to be used headless, graphic effects are not needed
So I optimized Windows 10 by enabling the high-performance power plan and disabling all visual effects.
This really gave the Celeron NUC I used a big speed improvement.

To make sure "ROON" will use the Amanero Combo384 module and not the internal Intel HD Audio soundcard as an output device, I disabled the "HD Audio" in the bios of my NUC.
This way I made sure that the audio signal doesn't have to follow an unnecessary long path.
I also made sure that the audio output was configured properly so I double checked it by
connecting the headless NUC on my TV and connect it to my DAC.
This way I could see what was going on.

After making the Amanero Combo 384 module my default audio output device in Windows 10, it was time to listen to ROON!


Configuring ROON SERVER

After I logged in with my trial account everything went very easy
Just enter the path your music collection and ROON already starts to index it.
This will take some time, after this the audio "end-point devices" have to be configured

Standard a lot of "output devces" are enabled by default like the "System Output"
I wanted that the audio only could go through my Amanero Combo384 so I disabled all other devices.

Then when I expected only one device would be visible, I noticed that there were two devices to choose from.
One "Amanero Technologies USB Driver" and one "Combo384 ASIO"
These audio output devices came from the installation setup of the Audio-Gd Amanero drivers.
I decided to active them both, to see which one sounded the best.

First I checked the "Amanero USB" output device:
Bellow you can see which sampling formats are supported
You can see they have different colors, the colors mean:

Formats in "Green" are supported in bit-perfect playback
Formats in "Yellow" are supported in bit-perfect played if the settings are adjusted, subject to the
device capability
Formats in "Red" require conversions during playback

Of course I was a bit disapointed to see that my Master 7 DAC with Amanero Combo 384 module
could only playback PCM till 384 kHz BitPerfect

But to my surprise when I looked to the other audio output device, called "Combo 384 ASIO" I saw:

That all formats were supported!
So in my case the "Combo384 ASIO" output device is the best device for the best quality.
So I was happy again, and very curious how "ROON" will sound

ROON exciting feature "Signal Path":

One very nice feature of "ROON" is that you can see the actual signal path of the music your a playing.
Just press with your mouse on the small "green" dot in the middle of the lower screen.

Then you will get this "pop-up"

"ROON" shows not only the signal path, but also let you know if the signal path is optimal
"ROON" uses again colors to categorize each step

Bright purple dots are the best, the stream is going from the file to the device without being modified.
if all steps are bright purple the signal path is clasified as "Lossless"
This is the best situation.

If one step in the signal path is "blue" instead of "bright purple" the signal path is clasified as: "Enhanced"
This means that the user enabled signal processing
The sound will still sound very good, but from a puriststic point of view it's a sign that the signal path is not optimal anymore. it has been modified.

When the mixer of the software does perform software-based volume adjustments or sample rate conversion before playing the audio. then "ROON" label the signal path as "High Quality"
Because no longer can be guaranteed that the output file will be 100% lossless...

Then when MP3 or low quality music files are played "ROON" automaticaly label the signal path as "Low Quality"

Time to play some music and to see how this "Signal path" works:
First I played a 32bit 96 kHz WAV file of an Pure Audio Blu-ray disc that I ripped with
the software program called: "Audacity"

When I played the music through the "Amanero USB" output device I noticed that "ROON"
showed me that the signal path was not 100% optimal
Because by the Output of the Mixer was an "green" dot instead of a "bright purple one"
So that means that the hardware and streaming technology that was used to render the audio stream
was not optimal...

Then I switched to the other music output/end-point device called "Combo384 ASIO"

Now the signal path was "Lossless" which is the preferred setting.
All dots after the steps are "bright purple"

So for me personally "Combo384 ASIO" is the best output device within "ROON" for my DAC.
Of course if you have another DAC the device output device can be different.

Now I wanted to know if "ROON" (and my DAC) could playback DSD music files
Ät the time of writting this review "ROON" cannot played back SACD.ISO files
like "JRiver" can.
But instead "ROON" can play DSD formats like: "DSF"and "DFF"


DSD64 played in ROON with the "Amanero USB" output device
The signal path is: "High Quality" so not optimal....

DSD64 played through the "Combo384 ASIO" output device, the signal is still "High Quality"
because my DAC doesn't support native DSD, so all DSD music files have to be converted
to PCM bt software.

Lets play some DSD128 files


With "Combo384 ASIO" output device, "High Quality" and not "lossless"
but still the music sounded still very good

Lets try some DSD256 :-)


When I played some DSD256 test files from "2L Nordic Sound" it became clear that the limit of
my Celeron CPU Intel NUC has been reached..
A pop-up came "An audio file is loading slowly. This may indicate a performance or hardware problem"
The music was now stuttering, and finally stopped playing.

But we have still one step to go...DXD


2L DXD flac file played through the "Amanero USB"

The same file played through the "Combo384 ASIO"

Remarkable was that the Intel NUC had less problems with DXD files (DXD = PCM)
Then with playing back DSD 128, 256 files.
The DXD music was played, but you could hear some digital artifact that something was not right

Conclusion about the hardware: Celeron Intel NUC:

So the Celeron Intel NUC (costing 250 euro's) with Windows 10 and ROON SERVER can playback:

PCM 16bit 44.1 kHz / 32 bit 192 kHz without any problems, bit-perfect if you use the "Combo384 ASIO"
output device driver.

With the "Amanero USB" output device driver the signal path is not optimal anymore...


Also you can play DSD64 files in "High Quality" without any problems.
So for people that don't want to invest too much money for a streamer or
for those how have a PCM based music collection, the Celeron Intel NUC with ROON
van be a very satisfactory solution.
I liked testing ROON very much.

I also was impressed by how ROON looked, and how excellent  the user experience was of this product
ROON is really a very nice looking and naturally feeling application that is very easy to use.

Listening test

But the biggest question is, how does it sound?
Will it be better than Daphile? or even better than JRiver?

No, "JRiver" still rules because it can playback SACD.ISO's and DSD 128, 256 files bit-perfectly
Also "JRiver" sounds more transparent and has more micro details.
But "ROON" comes very close, and the user experience of "ROON" is much, much better then "JRiver"
I think "ROON" will be my streaming solution in the future, when maybe SACD.ISO files are supported
I also hope that the Amanero Combo384 module will be better supported in the future.

But "ROON" sounded very good, on my PureAudioProject Trio Voxativ open baffle loudspeakers you will hear every micro detail what is on the recording, but if you have normal Hi-Fi loudspeakers (and not High-End loudspeakers)
you will probably not hear any differences between "ROON" and "JRiver", so small are they.
You also have to ask your self how much you are willing to pay for extra User Experience and the great "ROON"
look & feel?

Personally I'm willing to pay more for the extra features that "ROON" has to offer
Especially I like the the "Signal path" feature, it gives me more clarity about my setup and therefore more peace that everything is connected as it should be.

Also the cover art, and the feature that you can read info about the artist is highly appreciated
Also a nice feature is that you choose your music on "format" (like DSD64, 128, 256 or DXD) "genre" or "year"

I can only say try "ROON" for you self, you will be not dissapointed

Audio Dandy - (Maarten van Druten)




Special thanks to ROON LABS from for making
this excellent and promissing product!



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