Introducing pleezer: a Deezer Connect player

[Tim Curtis]

I've just released pleezer v0.17.0 on GitHub. You might call it the "Audiophile Edition" and I'm pretty proud of it.

This release introduces TPDF dithering. That should be standard practice when requantizing audio, but is often overlooked. Beyond simple dithering, I made it a dithered volume control so that it scales with the magnitude of the actual signal. I was pretty astonished by its audible benefits: cymbals gained clarity, ghost notes became more distinct. That alone would have been worth it.

Encouraged, I went on to implement Shibata noise shaping, using newer curves than those found in SoX. There are 7 selectable shaping levels, making pleezer one of the most capable open-source dithering systems out there. To my knowledge, only SoX and a handful of other tools offer comparable functionality.

Output format (S16, S32, etc.) guides the dithering logic. By default, noise shaping is set to level 3, which balances noise suppression with stability.

Advanced users should fine-tune:

Code:

--dither-bits: set to your DAC's effective resolution (or 0 to disable)
--noise-shaping: select level 1–7 (or 0 to disable)

To estimate dither bits from spec sheets:

From THD+N in dB: (-dB - 1.76) / 6.02 → e.g., -118 dB ≈ 19.3 bits
From % THD+N: (-20 * log10(%THD+N) - 1.76) / 6.02 → e.g., 0.0002% ≈ 18.6 bits
Smooth Playback, Zero Fuss

And one more thing: a long-standing bug caused pleezer to ignore S32 output settings on moOde, silently reverting to S16. This is now fixed.

Fantastic :-)

I see from the readme:

--dither-bits is a user calculation using 6.02 as the divisor in the two formula options
--noise-shaping are preset options:

Level 0: No shaping
Level 1: Minimal shaping
Level 2: Conservative shaping
Level 3: Balanced shaping (default)
Level 4–7: Aggressive shaping — reduces in-band noise further but shifts energy >15 kHz (use with caution)

I'll add these to the settings and bump to 0.17.0 for upcoming release 9.3.3