3 ms·

There was a program called "amp" that used fast integer math. I compiled it on an SGI Indigo running at 30Mhz and it would play up to 256kbps files using 90 pe

There was a program called "amp" that used fast integer math. I compiled it on an SGI Indigo running at 30Mhz and it would play up to 256kbps files using 90 percent of CPU.

marcodiego 6y ago
MIPS at 30Mhz is comparable to contemporary pentiums at much higher frequency of the era. The Indigo probably had faster memory, io and bigger caches than pc's mere mortals could buy. The comparison is simply not fair. But this program called "amp"... I'm very curious to see if it could be compiled to run on a recent machine.
- ddingus 6y ago
  Let me see if I can track it down... I agree with you, but 30Mhz! That is a very low clock for 256kbps decode. MIPS did very significantly outperform Intel at that time. http://www.mp3-tech.org/programmer/sources/amp-0_7_6.tgz http://www.mp3-tech.org/programmer/sources/amp-0_7_6.tgz Found it. An Indigo sat in the office for a time playing tunes from an NFS share we would populate. I eventually took it home to do the same thing. I forget how I parted ways with that old box. I am not inclined to build it at the moment, though it may well make for a great micro controller project one day.
  - marcodiego 6y ago
    Nice! Still compiles with a minor modification: added a break on the default case of a switch. Time signature is wrong when playing though. Edit: Fixed: add "frequency = frequency/2;" after the comment /* Set the output frequency */ in file audioIO_Linux.c
    - ddingus 6y ago
      Cool! I liked the quality output of that player at the time. Highs were clean. Does it still hold up? Maybe I will build it just for grins myself. Thanks for the tips.
      - marcodiego 6y ago
        I can't critically evaluate the quality since I have no high quality mp3 nor Hi-Fi audio devices. An old recording of mine http://marcodiegomesquita.tripod.com/rda.mp3 http://marcodiegomesquita.tripod.com/rda.mp3 sounded with very unsaturated bass; which is good, I think I recorded/mastered it wrongly or the software I used at the time decoded it like amp decodes it. It actually sounds really good with amp. But yes, it uses very little cpu. Maybe less than dosamp.
        ddingus 6y ago
        I had similar experiences. Yeah, I need to build it now. Have a few tracks that often have watery highs, just not crisp. Amp played them great. Maybe I will play your track after the family activities. Edit: Except access denied, lol. No worries.
        marcodiego 6y ago
        Hugh of death likely. I can download it correctly from here: https://marcodiegomesquita.tripod.com/ https://marcodiegomesquita.tripod.com/
        ddingus 6y ago
        Cool, thanks.
- anthk 6y ago
  Slackware still has amp.
  - ddingus 6y ago
    What version?
    - anthk 6y ago
      Slackware? 14.2
      - ddingus 6y ago
        I was wondering about amp. Maybe a newer one exists? Sorry to be unclear.
        marcodiego 6y ago
        It is available from debian archive: http://archive.debian.org/debian/pool/non-free/a/amp/ http://archive.debian.org/debian/pool/non-free/a/amp/

There was a program called "amp" that used fast integer math. I compiled it on an SGI Indigo running at 30Mhz and it would play up to 256kbps files using 90 percent of CPU.

marcodiego 6y ago

MIPS at 30Mhz is comparable to contemporary pentiums at much higher frequency of the era. The Indigo probably had faster memory, io and bigger caches than pc's mere mortals could buy. The comparison is simply not fair. But this program called "amp"... I'm very curious to see if it could be compiled to run on a recent machine.

ddingus 6y ago
Let me see if I can track it down... I agree with you, but 30Mhz! That is a very low clock for 256kbps decode. MIPS did very significantly outperform Intel at that time. http://www.mp3-tech.org/programmer/sources/amp-0_7_6.tgz http://www.mp3-tech.org/programmer/sources/amp-0_7_6.tgz Found it. An Indigo sat in the office for a time playing tunes from an NFS share we would populate. I eventually took it home to do the same thing. I forget how I parted ways with that old box. I am not inclined to build it at the moment, though it may well make for a great micro controller project one day.
- marcodiego 6y ago
  Nice! Still compiles with a minor modification: added a break on the default case of a switch. Time signature is wrong when playing though. Edit: Fixed: add "frequency = frequency/2;" after the comment /* Set the output frequency */ in file audioIO_Linux.c
  - ddingus 6y ago
    Cool! I liked the quality output of that player at the time. Highs were clean. Does it still hold up? Maybe I will build it just for grins myself. Thanks for the tips.
    - marcodiego 6y ago
      I can't critically evaluate the quality since I have no high quality mp3 nor Hi-Fi audio devices. An old recording of mine http://marcodiegomesquita.tripod.com/rda.mp3 http://marcodiegomesquita.tripod.com/rda.mp3 sounded with very unsaturated bass; which is good, I think I recorded/mastered it wrongly or the software I used at the time decoded it like amp decodes it. It actually sounds really good with amp. But yes, it uses very little cpu. Maybe less than dosamp.
      - ddingus 6y ago
        I had similar experiences. Yeah, I need to build it now. Have a few tracks that often have watery highs, just not crisp. Amp played them great. Maybe I will play your track after the family activities. Edit: Except access denied, lol. No worries.
        marcodiego 6y ago
        Hugh of death likely. I can download it correctly from here: https://marcodiegomesquita.tripod.com/ https://marcodiegomesquita.tripod.com/
        ddingus 6y ago
        Cool, thanks.
anthk 6y ago
Slackware still has amp.
- ddingus 6y ago
  What version?
  - anthk 6y ago
    Slackware? 14.2
    - ddingus 6y ago
      I was wondering about amp. Maybe a newer one exists? Sorry to be unclear.
      - marcodiego 6y ago
        It is available from debian archive: http://archive.debian.org/debian/pool/non-free/a/amp/ http://archive.debian.org/debian/pool/non-free/a/amp/