Page 4 of 4 FirstFirst ... 234
Results 46 to 52 of 52

Thread: After 5 years it finally begins

  1. #46
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    10,165
    Looking really good! Very cool!!!

    I assume you can flip the 045 horn and M2 horn and compare that with this configuration. I am not suggesting that you should change your orientation, but I would be curious to see how flipping it would affect the sound.


    Widget

  2. #47
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,090
    Those look great!

    Rob
    "I could be arguing in my spare time"

  3. #48
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    521
    They look awesome!!

  4. #49
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,640
    Quote Originally Posted by sebackman View Post
    Good friends allways help :-)

    Today was a good day. After +5 years the fronts are finally done, except for the cloth on the fronts........

    I will try to measure over the weekend. 4-way active with SUB1500 subs XO @ 80Hz, 1400PRO from 80-800Hz, 2451BE from 800-10k and 045 above. I have no idea if it works or if it will sound disaster. The M2's will have to act reference.

    This is fun!
    Hi sebackman,

    Very nice work, and the results.
    I wonder 800Hz VHF crossover is meay too low for M2 horn. I would suggest 1kHz or even 1.2kHz as can be seen from the 2451Be/Trx measurements.

    Regards,
    Ivica

  5. #50
    Senior Member
    Join Date
    Nov 2008
    Location
    Gothenburg, Sweden
    Posts
    761
    This is so cool

    If you get any 045s over when you are finished, I might be interested. One of mine 045Be are faulty.

  6. #51
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    535
    Short update.

    Sorry bubbleboy76, no spare 045's. Check with LN.

    Ivica, I have not gotten so far to figure out XO yet. The 1400PRO is clean to about +1200Hz so I might potentially increase to 1kHz XO as I have no bass in these, so very limited cone travel. I don't know if that made any difference when designing M2 but 2216 will have to generate some real cone movement to produce bass.

    I have finally started to prepare for the XO and DSP correction file. The JBL M2 file does not seem complicated and in the BSS version, there are 17 PEQ points for each driver but no FIR or phase corrections. That means that the chosen XO points and the cabinet are very well integrated indeed. The delay in the M2 is somewhat surprising long at 271ms. To determine the acoustic delay in mine I just shot an MLS puls on each driver and note the flight time/distance the system gives me to a fixed point (mic) about 2 meters out and use the difference as a basis. Some very advanced tools in the form of a "setsquare" direct on the monitor was used to determine that the peaks matched. Delay was calculated at 125ms for the woofer and 427ms for the 045.

    Name:  IMG_7388.jpg
Views: 93
Size:  195.3 KB

    A first set of data wa collected out doors with no flat surfaces within 5m, except for the ground. Hight of pole mount was just above 2m. A bit chilly at 10 degrees C, but with a lot of coffee it was fine.

    Name:  IMG_7399.jpg
Views: 95
Size:  368.2 KB

    I order to get a reference for timbre a very competent monitor in the form of an active Genelec DSP studio monitor was collected. Very valuable to have a good ref. The Genelec is within +/- 1,5db 58Hz to 20kHz with clean phase all the way. That is not too shabby.

    Name:  IMG_7432.jpg
Views: 95
Size:  186.7 KB

    Name:  Genelec 5ms curve.png
Views: 94
Size:  108.6 KB

    Best reagards
    //Rob
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  7. #52
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,640
    Quote Originally Posted by sebackman View Post
    Short update.

    Sorry bubbleboy76, no spare 045's. Check with LN.

    Ivica, I have not gotten so far to figure out XO yet. The 1400PRO is clean to about +1200Hz so I might potentially increase to 1kHz XO as I have no bass in these, so very limited cone travel. I don't know if that made any difference when designing M2 but 2216 will have to generate some real cone movement to produce bass.

    I have finally started to prepare for the XO and DSP correction file. The JBL M2 file does not seem complicated and in the BSS version, there are 17 PEQ points for each driver but no FIR or phase corrections. That means that the chosen XO points and the cabinet are very well integrated indeed. The delay in the M2 is somewhat surprising long at 271ms. To determine the acoustic delay in mine I just shot an MLS puls on each driver and note the flight time/distance the system gives me to a fixed point (mic) about 2 meters out and use the difference as a basis. Some very advanced tools in the form of a "setsquare" direct on the monitor was used to determine that the peaks matched. Delay was calculated at 125ms for the woofer and 427ms for the 045.


    A first set of data wa collected out doors with no flat surfaces within 5m, except for the ground. Hight of pole mount was just above 2m. A bit chilly at 10 degrees C, but with a lot of coffee it was fine.

    I order to get a reference for timbre a very competent monitor in the form of an active Genelec DSP studio monitor was collected. Very valuable to have a good ref. The Genelec is within +/- 1,5db 58Hz to 20kHz with clean phase all the way. That is not too shabby.

    Best regards
    //Rob
    Hi Rob,

    Nice to be seen that THE PROJECT advanced.
    From the point of LF bass response I would not expect any spectacular results from the mentioned drivers even with the larger EQ applied, especially in such small box. From the simulation point using over 150Lit bass-reflex box with 2216nd drivern can reproduce a kind of "usable bass response".
    But using 15-inch driver over 500~600 Hz may produce a "directivity" problem, especially if such "wide dispersion" horn as M2, is applied. Using 'smaller diameter driver' would improve such "problem".
    Using here 14-inch driver over 1kHz may would introduce , such mentioned "directivity" issue. But as can be seen on JBL EON 615 solution a kind of "slot dispersion bass cover" would be helpful, but 'scalled' to the bass driver size

    https://reconingspeakers.com/product...plate-5039904/

    I believe that 'pure rectanglar' cover round 8-inch width can sovle "the problem".

    Regards
    Ivica

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. What determines where overboard begins?
    By Ducatista47 in forum General Audio Discussion
    Replies: 25
    Last Post: 11-16-2015, 06:52 PM
  2. First Large Altec Speakers Aquired, Now the Work Begins! Advice Welcome.
    By IowaClass65 in forum Lansing Product Technical Help
    Replies: 13
    Last Post: 11-17-2014, 09:40 AM
  3. 4430's... the wait begins.
    By DMMD in forum Lansing Product General Information
    Replies: 34
    Last Post: 05-31-2005, 12:40 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •