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what to blame for distortion?

Discussion in 'Archived Threads 2001-2004' started by Yoon Lee, Jul 2, 2002.

  1. Yoon Lee

    Yoon Lee Stunt Coordinator

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    if you're having distortion or not so clean sound, which component is mostly/least likely the cause of it? Could it be CD player, pre/pro, cable, or power amp?
     
  2. Yoon Lee

    Yoon Lee Stunt Coordinator

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    Or, could it be from CD recording itself?
     
  3. Fredrik E

    Fredrik E Stunt Coordinator

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    Most likely the power amp, or, sometimes, the CD recording in itself.
     
  4. John Garcia

    John Garcia Executive Producer

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    The MOST likely culprit is the amp being overdriven, but it could be a number of things. Distortion is when there is insufficient power to properly drive the speaker. Noise/background noise/poor recording is something entirely different.
     
  5. John Royster

    John Royster Screenwriter

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    Sometimes distortion on the CD. I've got tons of poorly recorded CDs.

    But if you are hearing distotion then either:
    A) overdriving speakers with too much power
    b) overdriving amp

    If the sound looses its dynamics and seems compressed and mushy, that's amp clipping. bigger amp would help.
     
  6. Yoon Lee

    Yoon Lee Stunt Coordinator

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    So, if you volume up your amp and hear distortion, then it's the amp having not enough power to drive speakers?
     
  7. Chu Gai

    Chu Gai Lead Actor

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    That's a tough one to say Yoon. There are a few possibilities.
    1) you could be driving your amp/receiver into clipping which can be looked at as operating the amp beyond its stated power specifications. For example. Say your amp has a power spec of 50 watts per channel, all channels driven, 20-20kHz, with THD+noise less than 0.08%. Now so long as you don't operate your amp past 50 watts (momentary surges are not a big thing) continuoulsy, all is fine. Once you go past that 50 watts, the distortion rises rapidly and not necessarily in a linear fashion. This distortion, will get large and have in it, significant amounts of even and odd order harmonic distortion components. Human hearing being what it is, finds the odd order distortion components very very unpleasant. This is a very simplified look at this, and if you wanted to find out more, you could certainly run a web search under the terms "clipping amplifier distortion" and get a more complete picture. If you want to find out, see about borrowing a friend's receiver that is rated for more power than you have.
    2) your amp is fine and your speakers have insufficient power handling capabilities. once you consistently exceed them, they too will distort.
    3) a driver in a speaker maybe defective. A certain volume is reached and something breaks up...could be a little crack, a slight tear...hard to say.

    there's a few more possibilities, but i'd turn my attention to the first two choices above.
    good luck!
     
  8. John Garcia

    John Garcia Executive Producer

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    It is MUCH more difficult to OVER power a speaker than to under power it, simply because with plenty of power one does not need to crank it up to the point of distortion to reach desired sound levels.

    If the problem is with one speaker, I would say something is damaged, though it would sound distorted most or all of the time, not just once in a while.
     
  9. John Royster

    John Royster Screenwriter

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    John's right. Much more likely the amp is clipping or distorting.

    Yoon, If you tell us your equipment I'm sure we can figure it out. Yeah, if you hear distortion at low volumes somethig is wrong.
     
  10. Yoon Lee

    Yoon Lee Stunt Coordinator

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    Thanks John,

    Denon 3802 as pre/pro
    Rotel 1075 (120w) power amp
    B&W 7NT speaker
    Sony DVP 560 DVD player as CD player until my Rotel arrives

    I don't hear distortion at low volume. And, not all the time. However, it seems consistantly happening around those sibilants. Also "ta-" sounds more like "ttsszza-".
     
  11. John Royster

    John Royster Screenwriter

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    Try swapping for another CD player. I too have a 3802 and using the DACs for CD playback sounded like poo. Lost a lot of detail and sharpness...kind of muddy sounding even in the highs.

    -edit- or couldn't be any of your gear at all. lots of hard sss or tss can be from your sidewalls. keep the speakers far away from those. Maybe just try hanging some blankets on the side wall to see if it tames it a bit, that way you can figure out if it is room or equipment related.
     
  12. Yoon Lee

    Yoon Lee Stunt Coordinator

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    It happens at exactly same place in a song in the same CD...all the time. So, certain thing in the CD is triggering the distortion in the system if it's not from the recording itself.
     
  13. John Garcia

    John Garcia Executive Producer

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    Are you using the DVDs DACs or the 3802s DACs? (I have a 560s also) Try switching between analog and digital to see if the problem persists. If the problem remains, there is a good chance it is the recording. The 560 has decent, but not great DACs also, which is why I don't use it as a CD player. Maybe there's a scratch on the CD?
     
  14. Yoon Lee

    Yoon Lee Stunt Coordinator

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    I'm using 3802's DAC. BTW while watching A Beautiful Mind, which has very low volume compared to other normal DVDs, I noticed very subtle and occasional popping sound, but my wife didn't notice it. I don't know if I'm seeing a ghost or not any more...
     

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