tidalplay

Tidal player for command line derived from tidalbar

Scope

The main idea of this project is to stream music from Tidal with target loudness (defined in EBU R 128) and the highest possible quality for the given equipment. To achieve this goal a player needs to know the following parameters of the playback equipment:

output voltage at 0 db
output impedance
headphones/speakers impedance
headphones/speakers sensitivity
maximum sample rate of DAC
maximum bit depth of DAC
ALSA name of the hardware volume control of the DAC

Signal path

graph LR
    A(Download Track)-->B(Apply -8 db Gain<br/>To Avoid Intersample Overloading);
    B-->C(Resample To<br/>Maximum Sample Rate);
    C-->D(Apply PCM headroom<br/>To Avoid DAC Overloading);
    D-->E(Convert To<br/>The Maximum Bit Depth)
    E-->F(Estimate Loudness);
    F-->G(Ajust Hardware Volume Control<br/>To Achieve Target Loudness);
    G-->I(Play);

Defaults

75 db target loudness to avoid hearing damage. Please note that some headphones does not give "flat" frequency response at such SPL. For instance, AKG K702 are optimized for 80-85 db. So some SPL-dependent equalization is desirable and will be implemented later.
To avoid ringing in poorly mastered music, the (sox) upsampling uses slow rolloff slighly apodizing low-pass filter with 85% bandwidth, based on archimago measurements.
4 db PCM headroom to avoid DAC overloading due to the internal resampling, dithering, filtering, etc, see Benchmark® and archimago articles for clarification.

Hardware support

Sources

Dell XPS 13 (9343)
Dell XPS 15 (L502x)
Sabaj DA3
Apple USB-C to Headphone adapter

Sinks

AKG K514
AKG K702
Sennheiser HD4.30

Feel free to provide corresponding parameters of any other Sources/Sinks.

Dependencies

keyring (https://github.com/jaraco/keyring) with cryptfile backend(https://github.com/frispete/keyrings.cryptfile)
pasuspender (part of pulseaudio-utils)
aplay, amixer (part of alsa-utils)
ffmpeg (<https://www.ffmpeg.org/)
sox (http://sox.sourceforge.net/)

Usage

Adjust MySink, MySource, CARD and target_SPL variables in tidalplay.py to match your playback setup and target loundess, respectively.
Open terminal.
cd to the tidalplay folder.
Type, e.g.,
./tidalplay.py playlist/4d056fb5-99f9-46ec-8ff3-f2dddd41821f or
./tidalplay.py artist/7144334 or
./tidalplay.py album/33376720 or
./tidalplay.py track/60815627 or ./tidalplay.py to shuffle your favorite tracks.