Home of the Squeezebox™ & Transporter® network music players.
Page 3 of 3 FirstFirst 123
Results 21 to 30 of 30
  1. #21
    Senior Member Wombat's Avatar
    Join Date
    Feb 2006
    Posts
    1,154
    Thank you! Would be interesting why SoX does so bad because it is perfect at downsampling. I also wonder how many devices offered in the past did really bad upsampling while called high-end audiophile. On the other side squarewaves are not exactly music so this all is very theoretical.
    Transporter (modded) -> RG142 -> Avantgarde Acoustic based 500VA monoblocks -> Sommer SPK240 -> self-made speakers

  2. #22
    Senior Member Archimago's Avatar
    Join Date
    Nov 2005
    Posts
    1,110
    Quote Originally Posted by Wombat View Post
    Thank you! Would be interesting why SoX does so bad because it is perfect at downsampling. I also wonder how many devices offered in the past did really bad upsampling while called high-end audiophile. On the other side squarewaves are not exactly music so this all is very theoretical.
    Yeah, not sure why with SoX. Since I didn't use gain parameters to decrease volume, it did warn me about clipping so it's doing it's diligence to warn the user of a problem.

    Yup... Square waves.
    Archimago's Musings: (archimago.blogspot.com) A 'more objective' audiophile blog.

  3. #23
    Senior Member
    Join Date
    Mar 2007
    Location
    UK
    Posts
    1,304
    Quote Originally Posted by Wombat View Post
    Would be interesting why SoX does so bad because it is perfect at downsampling.
    With down-sampling, there is nothing to do in terms of level adjustment. With up-sampling, you might need level adjustment. But it seems Sox doesn't do automatic level adjustment, hence the difference for up-sampling and down-sampling.

    But, as Archimago says, Sox does provide warnings so you can make the level adjustment yourself (e.g. gain -3.5) when a conversion needs it.
    Darren
    Check it, add to it! http://www.dr.loudness-war.info/

    SB Touch

  4. #24
    Senior Member Wombat's Avatar
    Join Date
    Feb 2006
    Posts
    1,154
    Quote Originally Posted by darrenyeats View Post
    With down-sampling, there is nothing to do in terms of level adjustment. With up-sampling, you might need level adjustment. But it seems Sox doesn't do automatic level adjustment, hence the difference for up-sampling and down-sampling.
    No, with downsampling there is enough clipping going on also with peaks that can reach above 1dB often enough. I use SoX myself and while testing how to downsample best i found that SoX does less clipping as other resamplers, especially when used with not so steep settings.
    I never liked the idea of upsampling so i don┤t know much about its behaviour.
    Transporter (modded) -> RG142 -> Avantgarde Acoustic based 500VA monoblocks -> Sommer SPK240 -> self-made speakers

  5. #25
    Senior Member
    Join Date
    Mar 2007
    Location
    UK
    Posts
    1,304
    Quote Originally Posted by Wombat View Post
    No, with downsampling there is enough clipping going on also with peaks that can reach above 1dB often enough.
    Often, really? Oh ... is this to do with the filter?

    Unless it's something to do with implementing the filter, I would expect that in general higher peaks will be far more likely with up-sampling than down-sampling (for the same reason you can't get higher digital peaks than the analogue signal!)

    If I am off base I am sure someone will pipe up.
    Darren
    Last edited by darrenyeats; 2013-05-11 at 00:57.
    Check it, add to it! http://www.dr.loudness-war.info/

    SB Touch

  6. #26
    Senior Member Wombat's Avatar
    Join Date
    Feb 2006
    Posts
    1,154
    I am no expert but the filters should be pretty similar for up and downsampling. The tradeoffs are pretty similar also. I don't know a recording with high samplerate to test with that has similar bad dr numbers as the ones Archimago used for upsample testing to have some comparison.
    Transporter (modded) -> RG142 -> Avantgarde Acoustic based 500VA monoblocks -> Sommer SPK240 -> self-made speakers

  7. #27
    Senior Member Julf's Avatar
    Join Date
    Dec 2010
    Posts
    2,510
    And this all would of course not be an issue at all if people would have kept following the original Philips/Sony recommendations of how much amplitude margin to leave in a digital recording (as specified in the original CD standards)....

  8. #28
    Senior Member
    Join Date
    Jan 2007
    Posts
    809
    Quote Originally Posted by Julf View Post
    And this all would of course not be an issue at all if people would have kept following the original Philips/Sony recommendations of how much amplitude margin to leave in a digital recording (as specified in the original CD standards)....
    That is a not uncommon issue in all human activity:

    Step 1: Don't follow instructions

    Step 2: Notice that things didn't turn out right

    Step 3: Attempt to fix the problem by adjusting or changing everything except the original error.

    ;-)

  9. #29
    Senior Member Archimago's Avatar
    Join Date
    Nov 2005
    Posts
    1,110
    Quote Originally Posted by Wombat View Post
    I am no expert but the filters should be pretty similar for up and downsampling. The tradeoffs are pretty similar also. I don't know a recording with high samplerate to test with that has similar bad dr numbers as the ones Archimago used for upsample testing to have some comparison.
    Well boys I found you some music where upsampling "needs" ALOT of headroom! Feast your eyes on probably the most horrendous LOUD, CLIPPED "album" ever to "grace" this terrestrial sphere (and managed to get published)... I give you Venetian Snares & Speedranch's mega-lo-fi electronica-noise album "Making Orange Things" (2001). Check out these DR numbers:

    ----------------------
    foobar2000 1.1.8 / Dynamic Range Meter 1.1.1
    log date: 2012-06-25 19:25:19

    --------------------------------------------------------------------------------
    Analyzed: Venetian Snares & Speedranch / Making Orange Things (DR0, FLAC)
    --------------------------------------------------------------------------------

    DR Peak RMS Duration Track
    --------------------------------------------------------------------------------
    DR0 0.00 dB -1.04 dB 4:26 01-Fire Beats
    DR0 0.00 dB -0.86 dB 4:42 02-We Hate Russell
    DR0 -4.56 dB -3.75 dB 2:32 03-Pay Me For Sex
    DR0 0.00 dB -0.44 dB 3:56 04-Cheatin'
    DR0 0.00 dB -0.46 dB 3:26 05-Unborn Baby
    DR0 0.00 dB -0.41 dB 4:05 06-Meta Abuse
    DR0 0.00 dB -0.32 dB 3:51 07-Molly's Reach Around
    DR0 0.00 dB -1.09 dB 3:33 08-Russell Hates this Track
    DR0 0.00 dB -0.76 dB 3:23 09-Viva Las Vegas
    DR1 0.00 dB -4.03 dB 3:39 10-Tushe Love
    DR0 0.00 dB -1.61 dB 3:51 11-Halfway Up the Stairway of Mucus
    --------------------------------------------------------------------------------

    Number of tracks: 11
    Official DR value: DR0

    Samplerate: 44100 Hz
    Channels: 2
    Bits per sample: 16
    Bitrate: 1292 kbps
    Codec: FLAC

    ------------------------------------

    Behold the horror of track 7 - "Molly's Reach Around" - nasty in more ways than one! RMS volume at -0.32dB. This is either an audiophile geek's nightmare or something for Ripley's (believe it or not, my friend actually listens to this!)...
    Name:  Original.jpg
Views: 170
Size:  17.2 KB

    Now let us reduce by 6dB's:
    Name:  -6dB.jpg
Views: 167
Size:  22.6 KB

    Upsample with Adobe Audition 3.0 to 32/192:
    Name:  Upsampled.jpg
Views: 169
Size:  26.4 KB

    Peak volume now is an amazing *-0.18dB*!!!

    So, I guess if you listen to this type of "music", you "need" 5.82dB of overhead! Congrats to the band...

    Of course, you would not expect anything like this with acoustic recordings...
    Last edited by Archimago; 2013-05-11 at 14:33.

  10. #30
    Senior Member Julf's Avatar
    Join Date
    Dec 2010
    Posts
    2,510
    Quote Originally Posted by Archimago View Post
    Behold the horror of track 7 - "Molly's Reach Around"
    Well, I guess someone was bound to produce the antithesis of John Cage's 4′33″...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •