Feature Request: Option to bypass audio processing and maintain original sample rate/bit depth

[epochaudio]

Title: Feature Request: Option to bypass audio processing and maintain original sample rate/bit depth

Description

I would like to request a feature to bypass all audio processing in Music Assistant and output the audio stream with its original sample rate and bit depth. This would allow for bit-perfect playback without any resampling or audio manipulation.

Use Case

• For users with high-end audio equipment who want to preserve the original audio quality
• For streaming high-resolution audio files without any downsampling
• For maintaining bit-perfect playback chain from source to output device

Proposed Solution

Add a new option in the stream controller settings:

• Add a "Bypass Processing" toggle in core settings
• When enabled:
  • Disable resampling
  • Disable volume normalization
  • Disable any audio effects/processing
  • Pass through the original sample rate
  • Maintain original bit depth
  • Keep original audio format (e.g., FLAC, DSD)

Technical Details

The implementation would require:

1. Identifying where the audio processing pipeline is in the codebase
2. Adding a bypass mode that skips the processing chain
3. Ensuring the original audio parameters are preserved throughout the streaming process
4. Adding appropriate UI controls in the settings

Benefits

• Better audio quality for audiophile setups
• Lower CPU usage (no processing overhead)
• True bit-perfect playback capability
• Support for high-resolution audio formats at native quality

Additional Context

This feature would be particularly useful for users who:

• Have DACs that handle their own processing
• Want to ensure no quality loss in their audio chain
• Need bit-perfect playback for specific use cases

Would this be something that could be considered for implementation?

[marcelveldt]

This is not the intended audience/usecase for Music Assistant.

Strictly taken we do close to no processing as soon as you disable volume normalization. The only thing we do is decode into PCM internally and that has to do with the fact we need to be compatible with a whole bunch of audio sources and target players - there is no loss of audio data at all.

Bits are bits. Audio quality is lost when you encode into a lossy format (or output to some shitty speakers), not in other ways.
Audiophiles that believe in these kind of myths can resort to software like Roon. We are more targeted to a broader audience.
Bit perfect is just marketing bullshit. Sorry to say it that way. I'm a believer of common sense and thats why/how I've built this all (and got me very far).

[yvmexcl]

It would save a lot of CPU cycles, I have problems with qbuz to play from 96khz 24bit and I think the limitation is the Rpi4, either in the same HA rpi4 or a separate rpi4, with other software that allows bitperfect I don't have it. Beyond marketing, it is being practical in the use of the limited CPU in the rpi

[marcelveldt]

That is actually another issue which has been fixed in the beta. We will provide a new stable patch soon

[z0mbieprocess]

While I agree with you @marcelveldt it's still a bummer my DAC LEDs do not turn cyan when playing DSD files.

[YannChris]

Hi,
In the settings of the player, I unchecked all options related to sound and selected all bitrates supported by the target speaker.
When playing files coming from a ripped CD, I notice:

• Input Flac 44,1 kHz / 16 bits
• Output Flac 96 kHz / 24 bits
  I doubt that this upsampling will improve the sound, but it stresses the processor (in my case, MA and HA are run in a virtual machine installed in a NAS).
  That's why I agree with the request and would appreciate to have a "bypass audio processing" option.
  Regards,
  Y.

[Lipown]

Yes please. I just noticed the same...

[OzGav]

We have closed this because the people posting misunderstand how this works. Did you read Marcel's reply?

[Lipown]

@OzGav yes I read that but still as @yvmexcl mentioned selecting all supported bitrates of my receiver making Music Assistant converting all streams to the highest bitrate setting. This making the process quite resource hungry. It would save a lot if I can do passthrough only...

[OzGav]

I would say if a RPi 4 can keep up with the stream, notwithstanding any spike in resource usage, then the project is meeting its intended objectives. If you are using a lesser processor than a RPi4 then you are probably out of scope. If you are using a RPi4 or equivalent and it is not able to keep up with the stream demands the you can open an issue about that.