Roon ARC bitperfect playback for DAPs

That’s only for iPhones. For Android ARC always do SRC to 44.1kHz.


Phone’s Android do SRC, not ARC.

plz android dap bit -perfect

plz android dap bit-perfect :frowning:

Sounds like you never used a DAP. No it doesn’t. In this case Roon does downsampling falsely assuming that it can’t handle higher sample rate. Apple Music, which don’t do any resampling, just works.

Well, Roon only does what the operating system says is possible. And as long as you’re using Android based DAP’s Roon will be told to downsample. So this request should be directed at Google rather.

Not really. Android apps can bypass the Android audio stack/mixer. For example the app called “USB Audio Player Pro” does it.
Roon said they may look into it but it’s a lot of work.

No. You’re understanding this wrongly. If the app sends higher bitrate than what device supports, the Android audio system will downsample it itself. But, in Roon ARC, ARC wrongly assumes it won’t support high bitrate audio and downsample against users’ will/what hardware really supports. In constrast Apple Music on Android just passes original samplerate music to Android audio system, making it handle SRC if needed and makes DAP possible to play it as-is.

For the moment ARC will benefit iPhone users without SRC. Android users will be left in the dust😔

For reference, here’s one exactly the same song from the same album playing on Apple Music and Roon ARC:

Roon ARC:

Apple Music:

Notice the sample rate display on the top right. Apple Music properly sends 24/192 to AAudio and DAP just plays that. Meanwhile Roon ARC does SRC for no reason and produces inferior 24/44.1 audio and send that to AAudio. It’s Roon’s fault, not anyone else.


Most android based DAPs have a modified android OS that bypass SRC so it can send bit perfect data to its internal DACs. I was quite surprised that Roon ARC didn’t work here.

For Android phones OS it will SRC to 48k. In your case it is SRC to 44.1k. I guess Roon ARC really needs more work here.

1 Like

This link should take you directly to the ‘Can I achieve Bit-Perfect Playback with ARC’ section of the ARC FAQ.

This topic has already an existing Feature Suggestion with many votes - everybody interested in this topic please (also) vote here:

Hi-Res on Android? UAPP integration? - Roon Software / Feature Suggestions - Roon Labs Community

The blue vote button is on the very top of the page:


1 Like

I use UAPP and DAP for years. I misunderstand the SRC on ARC’s signal path. I thought it is Android’s SRC.
ARC use formal API to ask Android device’s current resampling rate, on most phones it is 24/48, on your DAP it is 24/44.1. ARC do in-APP SRC when source’s resolution is different from what it ask from Android device.
So the problem is ARC has no formal way to know it is running on special DAP unless DAP reply API with specific result and ARC knows it.
Yes ARC can ignore Android device’s current resampling rate like other APP but it looks like Roon Labs has their plan on ARC’s DSP functions.

this thread here is for ARC, whereas the other one is apparently for Roon Remote. Both feature requests are valid as IMHO both apps should be able to deal with Android DAPs in the best possible way: fully-featured Android DAPs (PCM768kHz, DSD512, full MQA decoding) are quite common and Roon currently ignores them.

Looking at the explanation on your website, you are intentionally resampling to a ‘native’ rate you ask from the device, but this has not been an issue for recent (maybe in the last 5 years) dedicated DAPs and media players. Nearly all of the recent Android based media player support different sampling rates and bit-depths. This is only an issue (most probably) on not audio specific devices or older devices, which are anyway not able to run recent Android systems.

So the reasoning behind the “resampling with better algorithms based on a native sample rate” is not a valid scenario anymore for serious audio devices. Many media players, including, for example, the native Qobuz application, do support that. I checked the media stream settings on Android and kernel settings of multiple devices from FiiO, iBasso, Hiby etc. and applications like Qobuz are properly configuring the system for a specific sample rate and bitrate.

Can you please be so kind to reconsider that and bring your application to the level of recent developments in Android audio devices? Especially for ARC?

You can at least make it optional. If you are worried, you can even make the current behaviour default, and when you select / unselect an option, the application just sets the expected sampling rate without asking for the native one.


Seems arc for android that bypasses the system resampling is on the way, according to Brian from Roon In reddit


Tried the new “bit-perfect playback” mode in the most recent Roon ARC release (Roon 2.0.5 and ARC 1.0.5 are live!) and it doesn’t change anything on my Android DAP: ARC still downsamples to 44.1 kHz (while the Apple Music app plays high-res fine)

It’s only for external DAC so no DAP support yet.

1 Like

tried ARC 1.0.5 in USB/bit-perfect mode on a HiBy New R6 (2020) running Android 9 outputting via USB-C to a Topping E50 DAC: everything downsampled to 44.1kHz, no MQA, just like without bit-perfect mode.