SPL Meter and sub calibration - I'm confused

Discussion in 'Archived Threads 2001-2004' started by Martin Rendall, Jan 7, 2002.

  1. Martin Rendall

    Martin Rendall Screenwriter

    Joined:
    Dec 5, 2000
    Messages:
    1,043
    Likes Received:
    0
    Trophy Points:
    0
    I did a search, and got more confused as I read. So, I need a clarification:



    Using my receivers test tones, I used my Rat Shack SPL meter to get 75dB all around, including the subwoofer. Having read about LFE +10dB boosts and such, I've realised that I may have set my sub 10dB too low. Did I?



    Should I adjust my sub to 75dB or 85dB? I want 2 channel music to be "right"...



    EDIT: FYI, my speakers are all set to small...

    Thanks,



    Martin.
     
  2. Drew Eckhardt

    Drew Eckhardt Stunt Coordinator

    Joined:
    May 10, 2001
    Messages:
    246
    Likes Received:
    0
    Trophy Points:
    0
    A true 75dB all arround is the correct setting.
     
  3. SkiingNinja

    SkiingNinja Second Unit

    Joined:
    Aug 14, 2001
    Messages:
    311
    Likes Received:
    0
    Trophy Points:
    0
    At lower listening levels, I prefer to trim the sub up a bit. When I play a movie loud, I trim it back to 75 or...sometimes still a little hot [​IMG]
    Sean
     
  4. Martin Rendall

    Martin Rendall Screenwriter

    Joined:
    Dec 5, 2000
    Messages:
    1,043
    Likes Received:
    0
    Trophy Points:
    0
  5. Jeremy Anderson

    Jeremy Anderson Screenwriter

    Joined:
    Nov 23, 1999
    Messages:
    1,049
    Likes Received:
    0
    Trophy Points:
    0
    On the majority of receivers, you set to the same level all the way around. But the Onkyo 595 and 696 (and possibly higher end models) have their internal subwoofer tones 10dB too low. So on those receivers, set to 75dB for the speakers and then 85dB for the subwoofer, and you're good to go.

    I also recommend getting a good calibration disc such as Avia or Video Essentials, since they have a lot more tests and tweaks to help you get the most out of your system (and your monitor/TV).
     
  6. RandyRush

    RandyRush Stunt Coordinator

    Joined:
    Dec 11, 2001
    Messages:
    61
    Likes Received:
    0
    Trophy Points:
    0
    Jeremy, as the owner of a 797, this is the first I have heard of the internal setting for the sub being low;maybe I have just missed it, but I have been wondering, after setting everything, why my boomer hasn't been the same; I will try to up it the additional 10 and see if that fixes the lack of punch. I was beginning to think my MK15" was losing its ability to perform the way it did before I calibrated! thx
     
  7. John H

    John H Second Unit

    Joined:
    Nov 27, 1998
    Messages:
    472
    Likes Received:
    0
    Trophy Points:
    0
    Stop!* Before you run home and set your subwoofer 10 dB higher than you've already set it, you need to read on and find out why this is not necessary.
    For consumers, we want things to be simple.* Up until recently, only serious enthusiasts would use an SPL meter to set the levels of their home theater equipment, let alone ask everyone to remember to set the LFE channel differently. For this reason, home Dolby Digital equipment is pre-set to play LFE data 10 dB higher than a main channel (or 10dB higher than the bass from a main channel).*It is only necessary to set the subwoofer relative to a main channel and the LFE level will be correct.
    *
    LFE Channel Explanation
    John
     
  8. Jeremy Anderson

    Jeremy Anderson Screenwriter

    Joined:
    Nov 23, 1999
    Messages:
    1,049
    Likes Received:
    0
    Trophy Points:
    0
    John H, the fact remains that the internal subwoofer test tone of the Onkyo 595 and 696 has been proven to be about 10dB too low when compared to a calibration disc such as Avia or VE. I don't have any experience with the 797 or higher models, so I can't say if their tones are correct or not, but anyone with those models should definitely double-check using a calibration disc to get the proper reference level. The majority of other receivers should be adjusted so that all channels are equal, since LFE data is automatically padded +10dB.

    Yes, the LFE channel has a maximum range 10dB higher relative to the other channels (meaning reference level will produce peaks of 105dB from the main channels and 115dB from the LFE channel). But you're not adjusting LFE level -- you're adjusting the level of the subwoofer in relation to the other speakers. LFE will automatically be padded the proper amount in relation to this setting.
     
  9. John H

    John H Second Unit

    Joined:
    Nov 27, 1998
    Messages:
    472
    Likes Received:
    0
    Trophy Points:
    0
    Jeremy,
    I was just posting a quote from an article which I suplied a link to.
    The original poster did not mention which manufactures receiver he was using. He was asking what was the technically correct level to calibrate his subwoofer in relationship to the other channels.
    I was not referring to the Onkyo models you mentioned. [​IMG]
    Actually the RS meter measures a subwoofer test tone 2-3dB low. So calibrating it's level 2-3dB lower than the other channels is correct.
     
  10. Jeremy Anderson

    Jeremy Anderson Screenwriter

    Joined:
    Nov 23, 1999
    Messages:
    1,049
    Likes Received:
    0
    Trophy Points:
    0
     
  11. John H

    John H Second Unit

    Joined:
    Nov 27, 1998
    Messages:
    472
    Likes Received:
    0
    Trophy Points:
    0
     
  12. Ted Lee

    Ted Lee Lead Actor

    Joined:
    May 8, 2001
    Messages:
    8,390
    Likes Received:
    0
    Trophy Points:
    0

Share This Page