linux/Documentation/sound/cards
Oswald Buddenhagen bcdbd3b788 ALSA: emu10k1: enable bit-exact playback, part 2: voice attenuation
The voice volume is a raw fractional multiplier that can't actually
represent 1.0. To still enable real pass-through, we now set the volume
to 0.5 (which results in no loss of precision, as the FX bus provides
fractional values) and scale up the samples in DSP code.

To maintain backwards compatibility with existing configuration files,
we rescale the values in the mixer controls. The range is extended
upwards from 0xffff to 0x1fffd, which actually introduces the
possibility of specifying an amplification.

There is still a minor incompatibility with user space, namely if
someone loaded custom DSP code. They'll just get half the volume, so
this doesn't seem like a big deal.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230514170323.3408834-8-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-05-16 11:11:04 +02:00
..
audigy-mixer.rst ALSA: emu10k1: enable bit-exact playback, part 2: voice attenuation 2023-05-16 11:11:04 +02:00
audiophile-usb.rst ALSA: doc: ReSTize Audiophile-USB.txt 2016-11-10 22:33:24 +01:00
bt87x.rst ALSA: doc: ReSTize Bt87x.txt 2016-11-10 22:33:26 +01:00
cmipci.rst
emu10k1-jack.rst ALSA: doc: ReSTize emu10k1-jack.txt 2016-11-10 22:33:22 +01:00
hdspm.rst ALSA: doc: ReSTize hdspm.txt 2016-11-10 22:33:28 +01:00
img-spdif-in.rst ALSA: doc: ReSTize img,spdif-in.txt 2016-11-10 22:33:31 +01:00
index.rst ALSA: doc: ReSTize img,spdif-in.txt 2016-11-10 22:33:31 +01:00
joystick.rst Documentation: fix input related doc refs 2017-10-12 11:14:06 -06:00
maya44.rst Documentation: sound: correct spelling 2023-01-29 09:23:45 +01:00
mixart.rst ALSA: doc: ReSTize MIXART.txt 2016-11-10 22:33:25 +01:00
multisound.sh ALSA: multisound.sh: update module namespace 2018-06-26 17:45:16 +02:00
sb-live-mixer.rst ALSA: emu10k1: enable bit-exact playback, part 2: voice attenuation 2023-05-16 11:11:04 +02:00
serial-u16550.rst ALSA: doc: ReSTize serial-u16550.txt 2016-11-10 22:33:29 +01:00
via82xx-mixer.rst ALSA: doc: ReSTize VIA82xx-mixer.txt 2016-11-10 22:33:23 +01:00