Macbook Pro Penryn Headphone Output Noisy??

Discussion in 'MacBook Pro' started by StuNew78, Mar 10, 2008.

  1. StuNew78 macrumors newbie

    Jan 15, 2007
    Hi All,

    Long time mac user here. Just upgraded my 2.16 to a base model Penryn 2.4 MBP.
    I'm a composer and live with my headphones on my head and plugged into either my ipod or my computer.
    I am very alarmed as to the high level noise floor on the headphone output, i mean it's not a huge amount, but considerably more than previous models.
    When audio is not being played for some time, the noise literally 'clicks' off and then on again when you playback....
    Completely not good enough for a 'Pro' machine in my opinion.

    Also, the drivers for XP are absolutely horrific. I'm getting horrible digital artifact noise and a much more shocking noise floor compared to OSX.

    any others with the same experience?

  2. alphaod macrumors Core


    Feb 9, 2008
    Yeah some people have reported hissing. It's not really bad, but I can hear it sometimes. It's just dirty electrical noise. You're pretty much out of luck unless you an external soundcard.
  3. bobcan macrumors 6502a


    Jan 8, 2007
    Sunny but Cold.. Canada
    Likely an Impedance Mismatch....

    This is likely an Impedance mismatch... my SR MBP has this issue, and it can be "solved" be inserting a Device that is used for Airline Audio Outputs (Shure/ Ultimate Ears/ and other Pro Audio manufacturers) make an In Line Device which has an Attenuator (fancy word for Volume Control) so you can better match and Raise the s/n (Signal to Noise) Ratio accordingly...

    Here is such a device, known as a Shure EA650; it will work with pretty much any 1/8" (3.5mm) headsets I am sure ;) :

    "Shure offers this level attenuator to reduce the level of incoming signals and allow for precise volume adjustment, minimizing background hiss...."
  4. Watabou macrumors 68040


    Feb 10, 2008
    United States
    Yeah I notice that too. When I remove the headphones it stops and the when I plug it in, it starts again. This happened to me only two times though. It's not doing it anymore. But Yeah I thought it was my headphones.
  5. StuNew78 thread starter macrumors newbie

    Jan 15, 2007
    Thats actually a good idea BW. It does indeed sound like quantization noise to me, as in, I don't think the analog output is being adjusted per se, just the level of digital audio hitting the D/A converter is very very low, so essentially, I'm using only a few of the lowest bits in the converter (which makes me worry about the audio quality)... so most of us think the output is being turned down, but no, in fact... just less digital info is getting to the converter.
    I'm using HD-25 sennhesiers @ 70 ohms, so they are quite low impedance compared to other headphones and require less volume ouput generally. The unit you've linked me to would be a good start to find a solution, now I can run the output at a nominal volume and use the bulk of the D/A resolution at the same time. Still, I never had an issue with my powerbook G4, 2.16 was worse, this 2.4 is kinda appaling. I'm using an mBox2 for ProTools work, and my lord, it's like night and day between the circuitury of that and my MBP.

    found another thread with this same problem so might close this off
  6. dsmartyn macrumors newbie

    May 14, 2009

    i have a mac book pro 2008 modal and i just bought some ultimate ears triple fi 10 pro and hooked up to my mac i could hear a constant "fuss" but i read this forum and plugged in the level attenuator and the fuss went completely!

    Thank you guys!!!
  7. offthesky macrumors newbie

    Sep 10, 2012
    this also worked for me(very cheap device): iLuv Black 3.5mm Splitter Adapter With Dual Volume Controls - I111. i turned the volume on the splitter down until i couldn't hear the hiss, then turned up the volume way up within osx to where music sounded great. was starting to feel ripped off with my $4k 17" mbp!
  8. w00t951 macrumors 68000


    Jan 6, 2009
    Pittsburgh, PA
    My Ultrasone Pro 750's are really good at making electronic interference sound like static. I bought a Fiio E17 - 0 interference, also drives high impedance cans with no problem.

Share This Page