Page 4 of 5 FirstFirst ... 2345 LastLast
Results 46 to 60 of 64

Thread: After 5 years it finally begins

  1. #46
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,170
    Those look great!

    Rob
    "I could be arguing in my spare time"

  2. #47
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    623
    They look awesome!!

  3. #48
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,703
    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

  4. #49
    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.

  5. #50
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675
    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: 1112
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: 1133
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: 1017
Size:  186.7 KB

    Name:  Genelec 5ms curve.png
Views: 1497
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

  6. #51
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,703
    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

  7. #52
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675

    Time for some update

    The curve for the 1400PRO, even in such small cabinet, is pretty encouraging. Not much bass however. I do XO at 80Hz to the subs.

    Here are some measurements

    1400PRO in cabinet

    1. Nearfield 170ms 3mm
    2. Far field 30ms 146cm outdoor
    3. Far field 30ms 146cm with EQ outdoor

    Name:  1400PRO NF 170ms.jpg
Views: 952
Size:  130.0 KB
    Name:  1400PRO FF 30ms 146cm outdoor.jpg
Views: 949
Size:  107.5 KB
    Name:  1400PRO FF 30ms 146cm with EQ outdoor.png
Views: 883
Size:  39.4 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  8. #53
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675

    Some data for Be's

    Here are some measurements for the 2451Be's in cabinet on my butchered M2 horns.

    No smoothing and please check scale change.



    1. Far field 6ms 154cm outdoor
    2. Far field 6ms 154cm with EQ outdoor

    Name:  2451Be FF 6ms 154cm outdoor.jpg
Views: 907
Size:  98.3 KB
    Name:  2451Be FF 6ms 154cm with EQ outdoor.jpg
Views: 897
Size:  104.3 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  9. #54
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675

    And 045 & total

    Here are some measurements of the 045 on the K2 S9900 horn incorporated into my butchered M2 horns.

    Also attached is a system plot on the full system.

    All these curves are taken outdoors on a 200cm speaker stand with no reflective surfaces within 5m except a sloping grass area 200cm below.



    1. Far field 3ms 145cm outdoor
    2. Far field 3ms 145cm with minimal EQ outdoor
    3. Far field full system 10ms 157cm outdoor with EQ & LR24 @ 800Hz and 13kHz

    Name:  045 FF 3ms 145cm outdoor.jpg
Views: 874
Size:  96.8 KB
    Name:  045 FF 3ms 145cm minimal EQ outdoor.png
Views: 810
Size:  37.3 KB
    Name:  3-way FF 10ms 157cm with EQ 24LR 800Hz & 13k outdoor.jpg
Views: 954
Size:  110.2 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  10. #55
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675

    In duty

    Here are a comparison between the old and the new. Slightly bigger but still acceptable by the Government.

    Name:  IMG_7517.jpg
Views: 869
Size:  105.7 KB
    Name:  IMG_7516.jpg
Views: 849
Size:  119.9 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  11. #56
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675

    Off the wall.....

    The room is about 5x8m and pretty decent when it coems to modes. 2x JBL SUB1500 subs do low end duty, one at the font of the room and one at the back.

    Electronics is still same old fully digital rig with Meridian pre, BSS DSP and Crown CTS amps. Soon to be turned into a museum piece….

    Drivers has no protection cap but a 8db attenuator. 045's are rather low sensitivity so they have no attenuator but are protected by a cap as they probably would react negatively on any voltage spike.

    This summer I will devote a few days to re-measure and se If I can get the XO's more seamless by playing with the delays and potentially fiddle little with the EQ points.

    Name:  IMG_7581.jpg
Views: 906
Size:  78.7 KB
    Name:  IMG_7583.jpg
Views: 964
Size:  41.3 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  12. #57
    Senior Member
    Join Date
    Nov 2008
    Location
    Gothenburg, Sweden
    Posts
    761
    Really cool. Nice work.
    Nice measurements as well.
    I would angle the L and R more inwards to reduce SBIR from sidewalls a bit, but that's just me.

  13. #58
    Member sebackman's Avatar
    Join Date
    Feb 2004
    Location
    Europe
    Posts
    675
    Hi bubbleboy76,

    Thank you.

    I agree, I would turn them in more if possible.

    The sides are both angled both inward and downward as much as the wall mount allows, please see better picture attached.

    The angles (down and in) are pretty spot on to where we sit.

    Wall reflektions is far from optimal but the M2 WG is pretty nice off axis, better then most alternatives so it is not perceived very sonically disturbing. Maybe I will add some some kind of foam there later.

    I can't really move them more inwards either, with this size screen.

    Compromises, compromises.

    The 045's blend very well with the Be's and allows for limited EQ on the Be drivers. I have no idea if it would have been better to put the 045 horns at the top as in the K2's, or if the centre position is equally good.

    I have not seen any documentation outlining which placement is preferred. Probably the top mount as this is what JBL does in the K2’s. But that could also be driven by aesthetics. For me it was a matter fitting into a small cabinet.

    Fronts are already made and hopefully I can get the cloth on this weekend. They attach with resessed magnets.


    I hope to be able to place the M2's better in the 2-channel room.


    Name:  IMG_7585.jpg
Views: 903
Size:  60.3 KB
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  14. #59
    Senior Member
    Join Date
    Nov 2008
    Location
    Gothenburg, Sweden
    Posts
    761
    Maybe you can try some temporary thick damping on the walls close to the speaker, just to see what happens.
    I would gain from it myself I think, but I can not do it due to WAF, so I donīt want to try it. I donīt want to know what I am missing...

    I think you placed the UHF-horns perfectly.

  15. #60
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    623
    They look great and thank you for sharing all of your work. They make for great reference as well.

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, 07:52 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, 10:40 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
  •