alsa-devel.alsa-project.org archive mirror
 help / color / mirror / Atom feed
From: Raymond Yau <superquad.vortex2@gmail.com>
To: ALSA Development Mailing List <alsa-devel@alsa-project.org>
Subject: Re: Mixer volume/decibel mapping
Date: Wed, 26 May 2010 07:00:22 +0800	[thread overview]
Message-ID: <AANLkTim77m6JMHSGCGJUN2h-3_Gsv7v7Afu7sbmhaK5_@mail.gmail.com> (raw)
In-Reply-To: <4BFBE056.9000706@ladisch.de>

2010/5/25 Clemens Ladisch <clemens@ladisch.de>

> Raymond Yau wrote:
> > I have doubt about DECLARE_TLV_DB_LINEAR(ak4396_db_scale,
> TLV_DB_GAIN_MUTE, 0);
> >
> > since the datasheet mention that dB range is only -48dB to 0dB
> >
> > ATT = 20 log10 (ATT_DATA / 255) [dB]
> >
> > How can AK4396 has scale of -inf DB to 0dB in the driver code  ?
>
> When ATT_DATA = 0, there is no output, which is an attenuation of -inf.
> The next value, ATT_DATA = 1, results in ATT = -48 dB.
>

But snd_mixer_selem_get_playback_dB_range() does not return 48dB
**

  reply	other threads:[~2010-05-25 23:00 UTC|newest]

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-19 16:34 Mixer volume/decibel mapping Sebastian H.
2010-05-20  7:34 ` Clemens Ladisch
2010-05-20  8:01 ` James Courtier-Dutton
2010-05-20  8:53   ` Raymond Yau
2010-05-20  9:41     ` Sebastian H.
2010-05-20 16:13       ` James Courtier-Dutton
2010-05-21  0:35         ` Raymond Yau
2010-05-21  1:30         ` Raymond Yau
2010-05-21  8:18           ` Sebastian H.
2010-06-07  3:37             ` Raymond Yau
2010-06-07  9:19               ` Sebastian H.
2010-06-08  1:03                 ` Raymond Yau
2010-06-08  6:02                   ` Sebastian Holtermann
2010-06-08 15:31                     ` Raymond Yau
2010-06-09 10:26                       ` Sebastian H.
2010-06-08  6:08                   ` Sebastian H.
2010-06-09  5:39                     ` Raymond Yau
2010-06-09  7:34                       ` Sebastian H.
2010-06-10  0:08                         ` Raymond Yau
2010-06-09  5:55                     ` Raymond Yau
2010-06-08  2:23                 ` Raymond Yau
2010-05-21  6:35         ` Clemens Ladisch
2010-05-21  6:51           ` Peter Ujfalusi
2010-05-21  9:56             ` Clemens Ladisch
2010-05-24  2:52               ` Raymond Yau
2010-05-25  8:38                 ` Clemens Ladisch
2010-05-25  8:43                   ` James Courtier-Dutton
2010-05-25  8:49                     ` Clemens Ladisch
2010-05-25 23:24                     ` Raymond Yau
2010-05-27 13:32                       ` Colin Guthrie
2010-05-29  3:54                         ` Raymond Yau
2010-05-29  1:57                     ` Raymond Yau
2010-05-29 18:46                       ` Colin Guthrie
2010-06-04 23:46                   ` Raymond Yau
     [not found]               ` <AANLkTik7mD1DAVWkOwM7sNu0EfgGApvzX9WRXWBOO4PI@mail.gmail.com>
2010-05-25  8:45                 ` Clemens Ladisch
2010-05-25 13:51                   ` Raymond Yau
2010-05-25 14:36                     ` Clemens Ladisch
2010-05-25 23:00                       ` Raymond Yau [this message]
2010-05-27  0:20                       ` Raymond Yau
2010-05-28 13:04                       ` Raymond Yau
2010-05-28 14:10                         ` Clemens Ladisch
2010-05-29  1:31                           ` Raymond Yau
2010-05-21 13:16           ` James Courtier-Dutton
2010-05-25  8:21             ` Clemens Ladisch
2010-06-09  6:19             ` Raymond Yau
2010-05-22  9:24           ` Raymond Yau
2010-05-20  9:20   ` Sebastian H.

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=AANLkTim77m6JMHSGCGJUN2h-3_Gsv7v7Afu7sbmhaK5_@mail.gmail.com \
    --to=superquad.vortex2@gmail.com \
    --cc=alsa-devel@alsa-project.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).