ARC FAQ

ARC FAQ

Overview

What is ARC?

Roon ARC allows you to take your Roon experience on the go.

ARC lets you browse your library, play local and streaming content, download local media to your phone, and update your collection by adding albums, building playlists, setting favorites, tags, and more. 


How much does ARC cost?

ARC is offered at no additional cost for all Roon users. 

What’s the difference between ARC and Roon? 

Roon is designed for inside the home. ARC is designed for outside the home. Roon supports more advanced functionality including DSP, metadata editing, and zone setup, whereas ARC offers Roon’s key functionality on the go. 


Does ARC connect to Roon Server?

Yes, ARC is a client of your Roon Server.

In other words, your server holds most of your Roon data, files, and preferences and ARC pings your server for this information. There’s deliberately not much data stored within ARC itself. Your server remains the brains of the operation so that ARC can remain as lightweight, and nimble as possible.

Because this setup requires regular communication between ARC and your server, you’ll want to ensure that your server is always on and has sufficient upload speeds. For best results, we recommend connecting your server via ethernet cable directly to your network.

ARC should perform without issue on most modern mobile networks, but feel free to use WiFi when possible for even faster results.


ARC offers limited offline play with any downloaded tracks, but will generally need to be connected back to your Roon Server for proper functionality and performance.  

How does ARC connect to my server? 

To ensure that ARC can communicate with your server when you’re on the go, your network needs to be configured for remote access. In many cases, this configuration (called “port forwarding”) will be done automatically. 

Port forwarding is widely used in gaming, CCTV, media players, and IoT devices to allow secure communication between devices on a home network and the wider internet. 

When Roon configures your network (or if you configure it manually), ARC will establish a secure line of communication to your server, authenticating your Roon account credentials and using an encrypted transport for all connections. 

Can I use ARC without a server? What happens if my server turns off?

ARC requires a connection to your server in order to run. Just as with Roon, you will have the best experience if your server is running at all times. 

If your server should go offline for a short period of time (for example a brief power outage), ARC will re-establish a connection as soon as the server comes back online. If your server is truly off or unreachable, you will need to rectify that in order to continue using ARC. 

If you wish to use ARC without a network connection, for example on an airplane or on a hike with no connectivity, you can play albums and playlists that you have downloaded to ARC in advance.

How does data syncing work between ARC and Roon?

Any changes you make on ARC will show up in Roon and vice versa.

Because of the myriad of situations that can come up when using a mobile app (e.g. editing a playlist in a tunnel), there may be a slight delay for ARC or Roon to update. However, in general, ARC should update automatically. If data ever feels out-of-sync, you can simply pull down to trigger a refresh and data sync.

How can I balance sound quality and data usage? 

ARC has the same audio infrastructure as Roon. Thus, it has the capacity to send lossless files to a connected USB DAC with uncompromised sound quality.

That said, there might be cases in which lossless audio might be overkill or where mobile data is limited or expensive.

ARC takes this into account, trying to find a balance between conserving mobile data and achieving the best possible sound quality. By default, ARC favors the highest audio quality on WiFi and “Balanced” (usually 320kbps) on mobile data.


If you would like to override this, you are able to adjust these settings.

  1. Under Settings > Playback you will see the option for audio quality and from there you can set exactly the quality level you’d like ARC to use for mobile data or WiFi.
Here’s exactly what our settings mean:

Setting

Result

Best for

Original Format

Best Quality Available

WiFi, when audio quality is prime concern

CD Quality

44.1-48kHz

Very good quality audio

Balanced

320kbits/s

Balance between data-saving and higher quality

Bandwidth Optimized

96-128kbits/s

Slow connections or conserving data


Can I use ARC in my car? 

Yes, you can! ARC works seamlessly with Apple CarPlay, Android Auto, Bluetooth audio, or as a wired Auxiliary input. Click here for our step-by-step CarPlay and Android Auto how-to.


Apple CarPlay and Android Auto allow you to view your artwork and control playback from your car’s interface. Many newer vehicles display album art when using a Bluetooth connection as well. 

Does ARC run on tablets or desktop platforms?

For now, ARC is optimized for use on phones. We hope to add support for tablets in the future. 

Can I download music for offline listening?

Yes, you can download music from your local music library for offline listening with ARC, click here for our offline listening how-to.

Simply go to any local album or playlist and click the download icon in the top right.



By default, ARC is set to download in original quality and preserve your data by only downloading on WiFi. However, you can override this setting and proceed to download from mobile data.

To do so:

  1. Go to Settings > Downloads and turn off “Download on Wi-Fi Only” or simply attempt to download something on mobile data and ARC will prompt you.
Downloaded content exists on the profile level and will be shared between profiles on the same account.

Can I update my library with ARC?

Yes, ARC supports library management on the go. This includes updating tags, playlists, and favorites, as well as adding and deleting content from your library. 

Can I transfer my queue between ARC and Roon zones in my home?

For now, ARC and Roon have separately managed queues, however, if you would like to borrow tracks from a recent Roon session in ARC, your Recently Played will show you the most recently played tracks from across Roon and ARC. Playlists are also shared and synced between Roon and ARC.

Does ARC Support Live Radio?

Not yet, but we plan to bring Roon’s Live Radio experience into ARC in the near future.

ARC Audio

How much mobile bandwidth does ARC use?

There are many factors that might affect ARC’s bandwidth usage. Let’s break them down.

First of all, ARC uses mobile bandwidth for several purposes—synchronizing between your library and your server, browsing within ARC, and playing music. Of those three, playing music is the largest consumer of bandwidth.


Can I control this?
Yes, you can use quality settings to control how much bandwidth is used by streaming music. Read below to see exactly what each setting means. 

How can I minimize bandwidth usage?

If data is a concern, we recommend using the “Bandwidth Optimized” setting as it has the smallest data footprint. 


How can I monitor bandwidth usage?

In iOS, navigate to Settings > Cellular and scroll down to find ARC.

For Android, navigate to Settings >  Network & Internet then Select Data Usage. From there select  View Details. Then, find ARC in your list of apps. 

If you would like to completely avoid data usage on the go, you are able to download local content directly to your device.


What do the playback quality settings mean?

  • Original Format

    • Files: The original file will be transmitted to ARC and decoded/played on your device

    • TIDAL: The highest quality format allowed by your subscription will be used

    • Qobuz: The highest quality format allowed by your subscription will be used

  • CD Quality

    • Files: The original file will be transcoded to 16bits at 44.1kHz or 48kHzTIDAL: ARC will request CD quality FLAC from TIDAL. 

    • Qobuz: ARC will request CD quality FLAC from Qobuz

  • Balanced

    • Files: Lossy files will be transmitted to ARC in original format. Lossless files will be transcoded to 256kbps Opus

    • TIDAL: We will request “High Quality” from TIDAL, typically this means 320kbit AAC

    • Qobuz: We will request “Standard Quality” from Qobuz, typically this means 320kbit MP3

  • Bandwidth Optimized

    • Files: Lossy files will be transmitted to ARC in original format. Lossless files will be transcoded to 96kbps Opus

    • TIDAL: We will request “Normal Quality” from TIDAL, typically this means 96kbit AAC

    • Qobuz: We will request “Standard Quality” from Qobuz, typically this means 320kbit MP3. 


Do I need to keep my server running to use ARC?

Yes. Think of your Roon Server at home as a personal streaming service. ARC needs to communicate with it in order to browse and play music. 

ARC does support offline operations in a limited fashion. You can browse and play files that were downloaded to ARC when the server was available, but for the full experience, ARC needs to be able to speak to your server. 


When I download files to ARC, what file format is downloaded?

The original file, in its original format, is downloaded from your server to ARC.


How does ARC play my local files?

Your files are streamed directly from your server.

What happens along the way is determined by your playback quality settings. By default, if you are on a cellular network, the files may be transcoded to a lossy format on the server to save bandwidth. If you are on a wifi network, files are streamed in their original format. These are the defaults, but you are able to customize each quality setting based on whether you’re on mobile data or Wifi.

For already downloaded files, playback settings will have no effect. If you’ve downloaded FLAC, we will play your unadulterated file directly from your phone.

If you have any questions, signal path will transparently show you what is happening at every step along the process.

Why is Automatic Volume Leveling the Default?

Tracks and albums can be mastered at wildly different volumes and dynamic ranges. In fact, over time, music has generally been getting louder. Without volume leveling, the differences between adjacent tracks would sound drastic (imagine listening to Simon & Garfunkel and Megadeth back to back).

We believe that smoothing these differences in perceived volume is important to ensuring a smooth listening experience, as such we’ve automatically enabled volume leveling. If you’d like to see exactly what’s happening, you can always see the adjustments being made in the signal path.

That being said, if you’d like to switch this feature off you can do so in settings.

Can I achieve Bit-Perfect Playback with ARC?

On iOS, we’ve confirmed bit-perfect output to USB DACs supporting DoP playback, MQA DACs, etc.

For Android, the answer is more nuanced. ARC shares Roon’s mobile implementation of RAAT, which uses Android's AAudio framework to deliver an audio signal to the operating system on your device.

Each Android device has a native sampling rate, determined by the operating system or device vendor. If we deliver audio to the device at any other sampling rate, it will be resampled by the system mixer, possibly introducing "bad" signal processes and audio impurities.

To prevent the operating system from interfering with audio quality, Roon detects the native sampling rate of your device and delivers the audio in that format. On most Android devices, this is usually a multiple of 48kHz. 

If you would like to pursue the highest audio quality possible on Android, a USB DAC will sometimes yield a higher sample rate than the native rate of the Android device.

For the best playback possible, regardless of platform, you’ll want to disable volume leveling and set your streaming quality preferences to “original format”. You’ll also want to check the playback quality settings. You can always use the signal path to confirm. 

​


What file formats does ARC support?

ARC supports all files supported by Roon.

How do I get the best sound quality from ARC?

If sound quality is your top priority, you’ll want to avoid using Bluetooth when possible. While it’s possible to get great sound quality with Bluetooth, there are many additional variables which can compromise your audio quality.

For best sound quality, we also recommend using a USB DAC. A USB DAC will sidestep your phone’s audio limitations and allow for higher fidelity. 

Within ARC, there are some additional steps you can take to ensure your sound quality is as good as it can be. You may want to disable volume leveling, and you’ll also want to ensure your music is playing back in its “original format”, with no additional encoding.

This can be confirmed by checking Signal Path, on the Now Playing screen. 


When using mobile data, your music may be reencoded to save bandwidth and ensure stable playback. To stream your files format over mobile data without conversions, you’ll want to change your playback settings to “Original Format”. Note that changing your mobile data settings may significantly increase the amount of mobile data that ARC uses.

Finally, it’s worth noting that right now lossless playback is easier to achieve on iOS than Android, due to the complexity of the Android ecosystem and its audio infrastructure. When configured as noted above ARC will do its best to lossless audio to Android for processing, but the operating system may modify the signal prior to output.

You can always confirm whether you’re playing back losslessly by checking Signal Path, and we look forward to expanding the capabilities of ARC on Android to make lossless playback possible in more scenarios.

Does ARC decode MQA?

No, but this is something we are considering for the future. ARC will play MQA files from Tidal or local storage at their native PCM rate of 44.1 kHz or 48 kHz.  

Does ARC Support DAPs?

Yes. ARC supports DAPs running Android 9 or above. We are beginning to test performance on various DAPs and are expanding our internal testing program. Please let us know which DAPs you are using with ARC and how your experience is.

Does ARC Support USB DACs?

Yes, ARC uses RAAT just like Roon and has the same capabilities with regard to USB DACs.


On iOS, bit-perfect playback is possible up to 768kHz / 24bit, and DSD256 using DoP. 


On Android, playback on a USB DAC will sometimes yield a higher sample rate than the native rate of the Android device.


Does ARC include EQ or other DSP functionality?

Not yet, but this is planned for the future.

Does ARC control Roon Zones?

Not yet. For now, ARC supports playback through your phone, tablet, or DAP using built-in outputs, USB, Bluetooth, and AirPlay depending on what your device supports. Allowing control of Roon zones is something we have planned for the future.

How does Bluetooth Impact Sound Quality?

When audio is transmitted from your phone or tablet via Bluetooth, it is compressed using a Bluetooth audio codec. Virtually all of the time, this is a lossy codec, either SBR or AAC. In particular, on iOS, it is always lossy, as iOS devices only support these two codecs.


It is possible for other codecs to be used if the mobile device and the Bluetooth device support it, and there is a lossless bluetooth codec on the horizon, but as of fall 2022, it is only supported on a few devices, so for all intents and purposes, it is best to assume that any situation involving bluetooth also involves lossy compression of the audio stream. 


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