AVIA calibration

Discussion in 'Archived Threads 2001-2004' started by Daniel T, Jun 7, 2002.

  1. Daniel T

    Daniel T Stunt Coordinator

    Joined:
    Jan 26, 2002
    Messages:
    93
    Likes Received:
    0
    Trophy Points:
    0
    I need a refresher on calibration. I first calibrated my system at 75db but I have recently added a dedicated amp with more power so I decided to calibrate to 85db as recommended for the AVIA. I first set my receiver volume dial to 70 and set all the speaker levels to 0. I then played the pink noise and adjusted the speaker levels till they read the following: Left +2, Center -1, Right +2, Rt. surround -1, and LT. surround +2. I have two subs; should they be calibrated to 85db also or should they be a couple db higher. When I calibrated I adjusted them for 85db; however, I popped in the Matrix and the bass is not quite as pronounce as when I calibrated to 75db. Maybe I did something wrong. Finally, I know setting the volume and adjusting the speakers makes all the speakers sound flow together; however, when I watch movies should I adjust the volume to the level for listening. Anyones help is greatly appreciated.

    Equipment
    Receiver H/K AVR55
    Amp Parasound 855a
    Speakers Axiom M3(fronts), VP100(center), QS4(surrounds), EP125 sub, and Infinity BU2 sub

    Thanks,
    Daniel T
     
  2. Vince Maskeeper

    Vince Maskeeper Producer

    Joined:
    Jan 18, 1999
    Messages:
    6,499
    Likes Received:
    0
    Trophy Points:
    0
    Daniel,

    1) 85db calibration point recommended by Avia simply provides a ref for playing back your soundtracks at the dolby specific ref level-- it's not really required, the important part is getting all the speakers at the same level.

    2) Most people calibrate a couple of clicks over 85 on the sub, but this is simply a matter of taste.

    3) As far as the less impact in the sub after calibrating to the 85 position- I'm not sure if I can offer a reason. It's possible your system is not providing linear adjustments for all channels with the master volume. The difference of 85 vs 75 db should simply be with the master knob- your individual speaker positions should be identical regardless.

    Try reducing the master volume and double checking against a 75db ref point. Leave all the individual speaker settings alone, and simply reduce the master volume-- does it go 75db all around? If not, it sounds like your receiver unit is not keeping the sub output the same relative to the master volume adjustments.

    If it does stay the same all around when reducing the master volume- the calibration is identical to what you had previously.

    The only reason I could think for a change in bass (besides a non-linear master volume issue) would be:
    a) Your change in the receiver sub output when re calibrating changed the headroom of that output, and thus you're getting a clipped signal (you made no mention of how hot you're running the sub output setting on your receiver, or what the previous settings were).
    b) you changed the gain setting on your subs amplifier- which can greatly affect the headroom and impact of the subs themselves. If possible, you should run the subs with the gain wide open, and adjust them using the control in the receiver.
    c) This might very well be an issue of perception- if after calibrating you stayed at the 85db position- the entire system was probably louder than you were used to- which will influence your perception of bass.
    d) When you said you got new amps, did this include the subs? Possible the new amps have a different sound.

    4) As far as adjusting the master volume- you should change it to whatever position you're comfortable with. If your master volume works correctly, it should adjust all the channels evenly- so as long as you leave the speaker controls alone and adjust the overall master volume... you should remain balanced and just adjust the overall levels.

    The master volume position you end up with at 85db spl with the AVIA disc is the Dolby Ref Output level- which is good to take note of if you ever have questions about your system or a soundtrack (as it's good to get an idea of your listening levels when asking questions, so ref level is a good median ref point for discussing these things with others)-- but there is no rule that you have to listen to soundtracks at that level.

    -Vince
     
  3. Daniel T

    Daniel T Stunt Coordinator

    Joined:
    Jan 26, 2002
    Messages:
    93
    Likes Received:
    0
    Trophy Points:
    0
    Vince,

    Thanks for the reply. I went back and ran Avia again to make sure all settings were correct for 85db. The speakers were fine but the sub was not correct. I recalibrated the sub and everything sounds great. I just wanted to make sure I was doing everything right. Thanks.

    Daniel T
     
  4. Daniel T

    Daniel T Stunt Coordinator

    Joined:
    Jan 26, 2002
    Messages:
    93
    Likes Received:
    0
    Trophy Points:
    0
    Vince,

    I bought a new Parasound 855a for my system. I am using my H/K recevier as a pre/pro. The amp is cleaner and brighter and I think that is why the bass sounded not quite the same. I watched Phantom Menace and the Matrix and everything sounds great now.

    Daniel T
     

Share This Page