Adire Rava Measurements/Need BFD?

Discussion in 'Archived Threads 2001-2004' started by Arron H, Jul 5, 2002.

  1. Arron H

    Arron H Second Unit

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    Okay, I spent about an hour with the Stryke disc this morning and was able to ascertain the following measurements for my Adire Rava:


    CorrectedUncorrected
    Hz1 Ft4 Ft1ft 4ft
    12.5 Hz75.571.5
    15.0 Hz7568
    17.5 Hz7364
    20.0 Hz82.575.5
    22.0 Hz8171
    25.0 Hz8675
    28.0 Hz8880
    32.0 Hz9185
    36.0 Hz9290
    40.0 Hz90.589.5
    45.0 Hz9183
    50.0 Hz92.577.5
    56.0 Hz9277
    63.0 Hz96.586.5
    71.0 Hz9585
    80.0 Hz92.586.5
    89.0 Hz8979

    1. Does anybody have the corrected values for 15, 17.5, 22, 28, 32, 36, 45, 56, 71, & 89?

    2. I measured the 1 KHz test tone at 90Db from 1 ft away from the left main and used this level for my measurements.

    3. Could I benefit from a BFD?

    Thanks for everyone's input.
     
  2. Arron H

    Arron H Second Unit

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    Okay, let's try this again:

    Measurements - 1 ft (corrected):

    12.5 Hz- 75.5Db
    20.0 Hz- 82.5Db
    25.0 Hz- 86Db
    40.0 Hz- 90.5Db
    50.0 Hz- 92.5Db
    63.0 Hz- 96.5Db
    80.0 Hz- 92.5Db

    Measurements - 4 ft (corrected):

    12.5 Hz71.5Db
    20.0 Hz75.5Db
    25.0 Hz75Db
    40.0 Hz89.5Db
    50.0 Hz77.5Db
    63.0 Hz86.5Db
    80.0 Hz86.5Db

    I have uncorrected values for 15, 17.5, 22, 28, 32, 36, 45, 56, 71, & 89 but need the corrections. Does anybody have these correction values?
     
  3. Geoff L

    Geoff L Screenwriter

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    Rat Shack correction values
    you wanted...
    14hz add +13.5
    16hz add +11.5
    22hz add +6.5
    28hz add +4.0
    31.5 add +3.0
    36hz add +2.5
    45hz add +2.0
    56hz add +1.5
    71hz add +1.5
    89hz add +1.5
    There you go....
    For 15hz split the difference between 14 and 16 = +12.5
    Not perfect but in the ballpark [​IMG]
    You might want to take measurements from 1-ft and then at your listening spot. Your spl volumes will be different but will give you a better idea of what the room is doing to your response with the sub in that location. If you move the sub to another spot be sure to take the measurments at the same volume and again from 1ft and from the listening spot. The room will be a big factor in your results. The important response is the listening spot!
    Experiment with different sub locations if possible to find your best trade of of flat response and extension. A BFD can/will help allot but finding the best spot to begin with will make it easier.
     
  4. Wayne A. Pflughaupt

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    Wayne
    Arron,

    The purpose of using dedicated sub equalizer is to correct room-induced response anomalies. Since a sub’s measured in-room response will vary greatly from one location to the next, it is best to take your readings from your primary listening position.

    Regards,
    Wayne A. Pflughaupt
     
  5. Geoff L

    Geoff L Screenwriter

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    Hi Wayne,
    I was editing and adding the same thing while you posted.[​IMG]
    Well Arron should be busy again for a while....
    Regards
    Geoff
     
  6. Arron H

    Arron H Second Unit

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    Geoff & Wayne,
    Thanks for your replies [​IMG] Believe it or not, the 1 ft measurements listed above are very close to one of the primary listening spots. I think that I will retake the measurements as close to the both primary listening spots as I possibly can.
    Geoff,
    I will definately play around with placement but first I am going to nail down the measurements from the primary listening positions. Thank you very much for filling in the gaps on the correction values. Very much appreciated [​IMG]
     
  7. Jack Keck

    Jack Keck Second Unit

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    Do I misunderstand what's happening here, or does the correction thing ean you're supposed to ADD the values to correct the RS SPL meter readings. It looks like Aaron subtracted the correction values. If they were added, teh response curve would be flatter, wouldn't it?
     
  8. Geoff L

    Geoff L Screenwriter

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    Im not exactly sure what Arron's got going on their!

    But yes, he should be adding the values to the Rat Shack meter readings he's getting for the freqs I posted and the others he has (if correct?) when testing sub freqs....

    C-weighted and slow responce.
     
  9. Arron H

    Arron H Second Unit

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    My first post should be ignored. When I copied it over from excel, it got completely jumbled. My second post does take into account the correction values, eg, from 4 feet away, the RS SPL read 70Db and I added 5DB correction value for a total of 75Db. I measured via C weighting, slow response.

    Here are my corrected values on a 2nd pass from 2 separate listening positions:

    Listening Position 1 (My listening position from 2 Feet)


    20.0 Hz - 68.5
    22.0 Hz - 70.5
    25.0 Hz - 69
    28.0 Hz - 78
    32.0 Hz - 81
    36.0 Hz - 83.5
    40.0 Hz - 80.5
    45.0 Hz - 81
    50.0 Hz - 77.5
    56.0 Hz - 72.5
    63.0 Hz - 80.5
    71.0 Hz - 80.5
    80.0 Hz - 78.5
    89.0 Hz - 76.5

    Listening Position 2 (My wife's listening position 7 feet)

    20.0 Hz - 64.5
    22.0 Hz - 63.5
    25.0 Hz - 63
    28.0 Hz - 67
    32.0 Hz - 72
    36.0 Hz - 80.5
    40.0 Hz - 79.5
    45.0 Hz - 81
    50.0 Hz - 73.5
    56.0 Hz - 62.5
    63.0 Hz - 71.5
    71.0 Hz - 71.5
    80.0 Hz - 69.5
    89.0 Hz - 69.5

    Position 2 looks preety bad but my wife does not seem to mind. Position 1 is not bad except for 56Hz. The Rava seems to roll off preety steeply after 28Hz but that is preety much in line with Adire's specs. I have read some posts that would seem to indicate that with proper placement, lower extension from the Rava is possible.

    I would like to move the Rava up front about 1/3rd of the wall away from the right front corner (either between the right main and the entertainment center or along the right side wall - both of these spots sound about the same). The Rava is very close to my current listening position and after getting on my hands and knees and listening to the bass in several locations around the room, the right front corner would be the best except that this is also where the front door opens, Doh! Therefore, it would need to go either between the right main and the entertainment center or about a third of the way down the right side wall.
     
  10. Geoff L

    Geoff L Screenwriter

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    Yah Arron, im sitting in your chair. lol
    Really the numbers looks pretty good, in your chair.[​IMG] Poor mama, probley dosn't know what shes missing.
    Generaly, corner placed on the 2 longest un-iterupted walls excite the most freqs. And free gain is always good, well not always if the responce is all over the place which can happen. All rooms are different and playing with placment and measuring is half the fun! Moving the sub as little a 6 inches can make a big differance.
    I got a really nasty 15 to 18db spike centered around 56hz just backwards from yours along with other much smaller freq problems. Of course we could'nt leave it that way, after hours of placement playing, gave in and bought a Sub EQ last year.
    If you eventually plan to go with a BFD or other Parametric EQ, Wayne P. and a number of others here really know their stuff and are always willing to help. Im rather a newbie to the serious eq stuff.
    Have fun with the Rava....
     

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