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[Tynach <tynach2@xxxxxxxxx>]

Nowhere in either the parent post, nor in the comments, is 'bang for the
buck' even talked about. The entire thing seems to be about choosing a
higher quality default sampling method due to the availability of faster
CPUs. In fact, libsamplerate is never mentioned by name, and src-sinc-.*
are only mentioned by listing them with a few others and deeming them
'indistinguishable'.

HOWEVER, in the comments they *do* mention that upsampling causes more
distortion than downsampling, and that sampling rates further apart
cause more than sampling rates closer together. This isn't terribly
important most of the time, except...

... Pulseaudio only supports configuring two sample rates at a time. So
you have a default lower one, and if an audio source has a higher sample
rate, it'll be upsampled to the alternative, higher sample rate.

So what if your alternative sample rate is much higher? I have a sound
card that supports 192000, what if I'm curious what that sounds like? I
have a fairly fast CPU (i7-4790K with hyperthreading disabled so that
each core works as fast as possible), and I have that set up as my
alternative sampling rate.

But the graphs only test conversion from 44100 to 48000. I have a
feeling that the differences will be *much* more noticeable on a setup
converting from 48000 to 192000.

But now I can't compare using src-sinc-.* because its been removed. And
seemingly with no discussion or reason.

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to pulseaudio in Ubuntu.
https://bugs.launchpad.net/bugs/1494155

Title:
  [mako] pulseaudio resample methos missing src-sinc-*

Status in pulseaudio package in Ubuntu:
  Won't Fix

Bug description:
  I tried to change the pulse resampling on my mako to src-sinc-best-
  quality and medium, to no avail.

  Later i found out that the pulse shipped with mako isnt capable of
  using these resampling methods.

  $ pulseaudio --dump-resample-methods
  trivial
  speex-float-0
  speex-float-1
  speex-float-2
  speex-float-3
  speex-float-4
  speex-float-5
  speex-float-6
  speex-float-7
  speex-float-8
  speex-float-9
  speex-float-10
  speex-fixed-0
  speex-fixed-1
  speex-fixed-2
  speex-fixed-3
  speex-fixed-4
  speex-fixed-5
  speex-fixed-6
  speex-fixed-7
  speex-fixed-8
  speex-fixed-9
  speex-fixed-10
  ffmpeg
  auto
  copy
  peaks

  while on an other system (non ubuntu touch) i get the correct
  resampling methods:

  $ pulseaudio --dump-resample-methods
  src-sinc-best-quality
  src-sinc-medium-quality
  src-sinc-fastest
  src-zero-order-hold
  src-linear
  trivial
  speex-float-0
  speex-float-1
  speex-float-2
  speex-float-3
  speex-float-4
  speex-float-5
  speex-float-6
  speex-float-7
  speex-float-8
  speex-float-9
  speex-float-10
  speex-fixed-0
  speex-fixed-1
  speex-fixed-2
  speex-fixed-3
  speex-fixed-4
  speex-fixed-5
  speex-fixed-6
  speex-fixed-7
  speex-fixed-8
  speex-fixed-9
  speex-fixed-10
  ffmpeg
  auto
  copy
  peaks

  
  ubuntu touch version:
  current build number: 23
  device name: mako
  channel: ubuntu-touch/stable/ubuntu
  last update: 2015-08-27 10:42:51
  version version: 23
  version ubuntu: 20150825.1
  version device: 20150819
  version custom: 20150825.1

  pulseaudio version:
  pulseaudio:
    Installed: 1:6.0-0ubuntu9.2
    Candidate: 1:6.0-0ubuntu9.2
    Version table:
   *** 1:6.0-0ubuntu9.2 0
          100 /var/lib/dpkg/status

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