#9641 BLOC 1.5-sof: test XO-1.5 audio recording levels

[Zarro Boogs per Child]

#9641: test XO-1.5 audio recording levels
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           Reporter:  dsd       |       Owner:  Quozl                            
               Type:  task      |      Status:  closed                           
           Priority:  blocker   |   Milestone:  1.5-software-later               
          Component:  kernel    |     Version:  Development build as of this date
         Resolution:  fixed     |    Keywords:                                   
        Next_action:  testcase  |    Verified:  0                                
Deployment_affected:            |   Blockedby:  9639                             
           Blocking:            |  
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Changes (by Quozl):

  * status:  assigned => closed
  * resolution:  => fixed


Comment:

 Tested using a recorder (a woodwind musical instrument) and the ALSA
 utilities arecord and aplay.

 On XO-1 SKU38 build 802 and XO-1.5 C1 build os119.

 The laptops were set side by side on a concrete slab in open air with a
 light wind, equidistant from the sound source.  The default volume setting
 was used.

 A sound level meter was placed between the laptops, also equidistant from
 the sound source.

 Commands used in Terminal:

 arecord --vumeter=mono --rate=44100 /tmp/test.wav
 ^C
 aplay /tmp/test.wav

 The musical instrument was played from a distance of about 70cm, at a
 volume to achieve a display of 90dBA on the sound level meter.

 Six test runs were made, using various pitches and cadences.  The sound
 level meter and the laptop display were monitored.  Each recording run was
 played back on one laptop after another.

 There was a slight difference between the laptops of about 5% in the
 arecord volume meter readings.

 90 dBA on the sound level meter was represented as 35% level on the XO-1
 MP, and 30% level on the XO-1.5 C1.

 There was no significant difference in the recordings when played back.

 Conclusion: the levels are adequate.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9641#comment:9>
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