radio shack and avia

Discussion in 'Speakers' started by Ronneil Camara, Dec 1, 2004.

  1. Ronneil Camara

    Ronneil Camara Stunt Coordinator

    Joined:
    Dec 2, 2002
    Messages:
    235
    Likes Received:
    0
    I know guys that these have been asked multiple times. My RS meter(new analog version) and avia disc just arrived today. I tried searching the archive but I couldn't find the detailed procedure on calibrating home theater speaker system. I also have some few questions.
    1. IIRC, on a post, it mentioned that when calibrating, reference level should be at 0. Does that mean that I have to put my Yamaha main volume to 0? If so, will it not damage my speakers?

    2. How do I read the analog (-10 to +6)?

    3. A & C weighting? :O

    4. Slow/Fast Response? What is it too?

    5. iirc, someone posted that changes on the values needs to be added to RS meter. Is that really needed when calibrating?

    6. Lastly, are there any difference when calibrating a main speaker and a subwoofer?

    I'm really excited to try it now but can someone help me find that detailed calibration please?

    Thanks,

    Ronneil
     
  2. Jeff Gatie

    Jeff Gatie Lead Actor

    Joined:
    Aug 19, 2002
    Messages:
    6,531
    Likes Received:
    15
    The instructions for use of the RS meter are right on the Avia disk, in the section on speaker calibration. It includes a video on how to set up the meter.
     
  3. Ronneil Camara

    Ronneil Camara Stunt Coordinator

    Joined:
    Dec 2, 2002
    Messages:
    235
    Likes Received:
    0
    I actually found it there. But I got confused when it was the subwoofer's turn. I set my yamaha main volume to 0db. I thought my yamaha doesn't have the feature that will allow me to set each speaker's level. Luckily, I found it in the manual. So, I set it to C weighting, SLOW response and 80db on the dial. I fired up the test tone in avia, left speaker until I reached the middle(0db) but with +1.5 something db. I did that for all the other speakers. After that, I went to the subwoofer configuraion. It played the left speaker test tone again and it was switching to the subwoofer test tone. When it played the subwoofer test tone, it spike to +6db. I even decreased the subwoofer level and reached -10 it was still high.

    Am I correct that the subwoofer level should match the other speaker's level in the meter?
    Do I need to change my dial to another db setting when calibrating the subwoofer?

    I will go over the dvd again.

    Thanks,

    Neil
     
  4. Jeff Gatie

    Jeff Gatie Lead Actor

    Joined:
    Aug 19, 2002
    Messages:
    6,531
    Likes Received:
    15


    There should be another level adjustment knob located on the subwoofer (or on the seperate sub amp if the sub is not self-powered). Turn that to about 1/4 and readjust the receiver level to 85dB. Using a combination of receiver sub level and the level control on the sub, you should be able to dial it in correctly.
     
  5. Ronneil Camara

    Ronneil Camara Stunt Coordinator

    Joined:
    Dec 2, 2002
    Messages:
    235
    Likes Received:
    0
    Wait, looks like I'm only doing 81db. I'm missing 4 decibels [​IMG]

    My sub is self powered(not passive). It's an SVS 20-39PCi. Currently, it's halfway. I'll do calibration again and start with 1/4 setting on the sub volume.

    This means, that the 80db dial should be use throughout the speakers.

    I got confused with this site, he used 70db for his speakers and he changed it to 80db when he was about to calibrate his sub. http://www.geocities.com/p_iturra/PCI.html

    And also, am I correct that I should point(40 degrees) my spl meter's mic to the speaker that I'm calibrating? Found that 40 degrees on this link, http://www.hometheaterforum.com/htfo...?postid=650553

    BTW, I'm using my tripod.

    However, in avia disc, the meter's mic was pointing the ceiling. This is confusing!

    What about this link, is it still needed even if I am using the new analog meter model? http://www.danmarx.org/audioinnovation/rsmeter.html
    If so, how do I make use of those numbers?

    TIA [​IMG]
     
  6. Ronneil Camara

    Ronneil Camara Stunt Coordinator

    Joined:
    Dec 2, 2002
    Messages:
    235
    Likes Received:
    0
    Hi Jeff,

    I just decided to place the tripod on top of my couch but I made it sure that the spl meter was at the same level as my ears and that it was pointing to the center speaker(or tv set) and at 45-50 degrees. When it was the surround speaker's turn, I didn't bother to move the meter. But I changed all the speakers to 80db + 5db which gives me 85db. For my sub, I brought it down to 1/4 on the knob. I set it the dial to 90db. I then adjusted the swfr level to -2db, which gives me somewhat 88db. I also didn't bother to move the meter. I played Spider Man 2, the part where Dr Octavia was demonstrating his invention, it was awesome. All the speakers are better now. But the sub wasn't shaking my couch as compared to the setting prior to calibration. I just added another 1/8 to the knob and BAM! The sound is really better now, way^10 better [​IMG]. I also tried the Pod Race in Star Wars 1, oh my, my pants and couch were being moved by the air that is produced by the 20-39PCi sub and the other speakers just makes the movie much more lively.

    I can say that having avia disc and an spl meter is not just a requirement. But the real thing here is the enjoyment/fun of calibrating! I know, I'm just in the beginning. In the future, I will study how to use the RCA output port on that meter and prolly download some opensource tool to generate some nice graphs. This way, I will be able to really understand what's going on. [​IMG]

    Lastly, my Yamaha receiver is capable of detecting how far the YPAO mic is, how is that going to be useful if I am now using an external meter?

    Thanks guys!
     
  7. Jeff Gatie

    Jeff Gatie Lead Actor

    Joined:
    Aug 19, 2002
    Messages:
    6,531
    Likes Received:
    15
    Excellent! The "point at the center speaker at about 45 deg." method is the one I use. It is also ok to bump up the sub a few dB, most on this site do this, especially for lower volume preferences because bass has a way of "disappearing" as the volume is lowered (a mental, not measured effect). I've calibrated 1/2 dozen setups for friends that knew nothing about it and every one has been amazed at the result. You are correct in saying that the SPL meter and a calibration disk are more than a requirement, they are mandatory to getting a system to sound correct.
     
  8. ScottCHI

    ScottCHI Screenwriter

    Joined:
    Feb 21, 2004
    Messages:
    1,292
    Likes Received:
    0
    "0" on the receiver's main volume control is not only irrelevant but meaningless
     
  9. Jeff Gatie

    Jeff Gatie Lead Actor

    Joined:
    Aug 19, 2002
    Messages:
    6,531
    Likes Received:
    15


    In my case, I calibrated '0' as reference on my Denon 3801, so it is not irrelevant or meaningless. It is convenient to do this if possible, if only to set an easily remembered reference level and allow lower volume levels to be displayed accurately as "-10" or "-20" (dB) from reference (on my particular unit).
     
  10. Ronneil Camara

    Ronneil Camara Stunt Coordinator

    Joined:
    Dec 2, 2002
    Messages:
    235
    Likes Received:
    0
    I read about the 0db reference level too. I guess, the real point is to get an almost equal sound pressure level each speakers in one point and that is the listening point.
     
  11. Hector.B

    Hector.B Stunt Coordinator

    Joined:
    Dec 6, 2004
    Messages:
    77
    Likes Received:
    0
    I had calibrated my speakers by pointing the SPL meter at each individual speaker and up by about 45 degrees, but the method of pointing it at your center speaker and then 45 degrees up makes much more sense since you are trying to achieve the same sound level from exactly one spot. Oh well, guess I'll just have to calibrate again (YES!). By the way I also have a Denon 3801 and I love it to death!
     
  12. Geoff L

    Geoff L Screenwriter

    Joined:
    Dec 9, 2000
    Messages:
    1,693
    Likes Received:
    0
    -0- is "meaningless" to those that have receivers that (DO NOT) allow one to set the master volume knob to -0- for referance when calibrating.

    For those people -0- IS meaningless, the master volume level will be whatever it is when you read 75 or 85db (Ref), depending on the calibration disc being used. For those people ~{they should make a note of where that volume level is/reads, to know where Ref is}~..!

    More and more receivers are allowing one to set the master volume to -0- for calibration (ref), but some still do not allow it.
    Like my older Yammi...[​IMG]

    Some people do not listen at Ref and calibrate at -10 under. Also many run the sub a little hotter than he rest of the speaks. This is due to lower volume listening and how our ears pick up bass at those lower spl levels.

    If you calibrate your sub at 75 or 85db matching the rest of the speaks, you are really 2-3db "hot", assuming your sub is some what flat. Hope I'm not confusing people even more, it has to do with how the meter handels the lower bass tone when calibrating. So if you set the sub tone at 88db an the rest at 85dd, your really running close to 4-6db hot. For low volume listening this is fine, but at -10 to Ref can be very taxing on ones sub.

    It is and can be very confusing with all the cali threads and information all over the plce. The (Avia disc) dose a "very nice job" in explaining things. Listen to it, all of it, and follow their directions and you should come out fine. It dose a nice job explaining things for calibrating your setup.

    Those bass correction numbers you read about, ignor them for now, they have to do with plotting ones subs freq response not calibating. Something you can do later to see how flat your sub is at the listening postion and if you have serious room mode issues.
    PEEKS AND OR NULLS.

    Follow the Avia disc and you should come just out fine!

    Cheers
    Geoff ¥
     

Share This Page