Page 112 of 113 FirstFirst ... 1262102110111112113 LastLast
Results 1,666 to 1,680 of 1683

Thread: JBL Master Reference Monitor

  1. #1666
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    623
    Quote Originally Posted by grumpy View Post
    Working entirely in one manufacturer’s ecosystem makes it a bit easier, for sure.
    So true, after finding about the line of BSS Contrio wall controls, I can’t go back!

  2. #1667
    Junior Member
    Join Date
    Dec 2020
    Location
    Melbourne
    Posts
    2

    Diy m2

    Hi All,

    I am new to the forum. I joined as I look to construct some DIY M2's.

    Firstly, a big thankyou to all members who have contributed to such an amazing resource of information.
    I have been reading as much as I have time for, and I greatly appreciate the efforts of all who have documented and compile/tweaked settings etc.

    I sent POS a private message with some questions regarding M2 crossover design.
    I tried to post publicly, but I think my message and content exceeded maximum limits.

    Anyway, I was hoping someone might have a link to a recreated cut sheet and design plan for the M2 cabinets.
    I.e. CAD cut sheet etc. Does this exist?

    It would be amazing to get these plans, linked on the crossover google link, including the 3D file for the port design etc.

    Thanks for your assistance.
    Many thanks

  3. #1668
    Member
    Join Date
    Aug 2014
    Location
    Sacramento
    Posts
    31
    Quote Originally Posted by pos View Post
    Their purpose is padding only (the crown gain structure is probably too noisy for a compression driver), but their effect cannot be neglected and the EQ preset sure takes all this into account.
    Even with a protection cap aimed at around 200Hz (1/4 of the actual acoustical crossover frequency), with the lap the cap sees a constant 20 ohm load compared to a more complex load without. This will change its transfer frequency and the final frequency response of the system.

    One of the things I intend to do is to measure the HF combo with and without the lap (keeping only the protection cap), and see how the frequency response changes, and tweak the EQ settings to compensate for the difference...
    Hello,

    I know that is years later.

    As the discussion goes around the purpose of the resistors and capacitors.

    I see it some thing like this:

    1 the capacitors provide DC and low frequency protection well below the crossover frequency.

    2 Padding to operate up in the amplifier power range where there is less noise.

    3 with R2 in parallel with the driver and R1 in series with the driver the impedance curve is much flatter and tamer with much less resonance to disturb the frequency response.

    Thought comments, agreements disagreement?

    Thanks DT

  4. #1669
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,942
    If you Google M2 passive crossover there is a diagram with corrections of the capacitor mis print,

    An explanation is given of the network.

    Yes it provides attenuation of approximately 9 dB and a slow 1st order high pass passive filter at approximately 1000 hertz. This significantly improves the signal to noise ratio of a horn when used Bi amplified application.

    There is no rocket science here and l doubt Jbl spent too much time thinking about it. Greg typically uses a -6 dB fixed pad when Bi amping a horn. Those Crown amps have massive output so the M2 pad is scaled accordingly. There’s nothing to it.

    A horn without a pad will exhibit noise problems heard as residual hiss and other artifacts that erode the noise floor and resolution of the system. We don’t want that so we insert a fixed pad.

    The network is there to back the warranty and mis use of the system in the event in of an amplifier malfunction. Scroll down this link to the diagram.

    https://www.avsforum.com/threads/diy...2852530/page-4

  5. #1670

  6. #1671
    Member
    Join Date
    Aug 2014
    Location
    Sacramento
    Posts
    31
    Thanks for the replies with links.

    I have an order in at Mouser for the 3.3uf + 4.7uf capacitors and resistors.

    POS I did note in one of your links that you speak of the passive network linearizing the impedance of the D2+ waveguide.

    I believe that will be true.

    I will test that with wit the analyzer on my bench. (APx555 plus calibrated microphones.)

    Thanks DT

  7. #1672
    Senior Member pos's Avatar
    Join Date
    May 2007
    Location
    France
    Posts
    2,628
    M2 tested on a klippel test bench at Erin's audio corner:
    https://www.erinsaudiocorner.com/loudspeakers/jbl_m2/

    Name:  CEA2034 -- JBL M2 (Crown iTech 5000 Amp; M2 Base Configuration).jpg
Views: 1314
Size:  69.0 KB

  8. #1673
    Member
    Join Date
    Apr 2020
    Location
    Bergen, Norway
    Posts
    30
    Excellent waveguide, 1-2 dB too hot tweeter and cabinet could and perhaps should be a little bit better resonance-wise. It's possible that some of those resonances could come from something being loose.
    This measurement also confirms the peaking from 7-11 kHz even with the M2 version of D2 that can benefit from adjustments in the dsp.

    The compression tests shows why a big ole speaker has its merits. Excellent stuff.

  9. #1674
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    623
    Very interesting, thanks for posting.

    He confirmed the 270hz issue that we found awhile back ago.

    Thanks,
    Scott

  10. #1675
    Junior Member SilvioNovais's Avatar
    Join Date
    Mar 2022
    Location
    Brazil
    Posts
    7
    Quote Originally Posted by pos View Post
    De acordo com Charles Sprinkle , o 2216ndi é um componente chave no design M2, e um grande fator na forma como o sistema soa graças ao seu comportamento dinâmico (compressão de baixa potência) e diretividade em torno do ponto de cruzamento (bem separações controladas).
    Quanto ao transporte, pesa cerca de 4,5 kg, por isso é provavelmente um dos 15" mais leves que existem no mercado.
    🟢Hello Friend! I'm quite confused about which speaker to use in my project.
    You commented on the 2216ndi, the original I believe is the 2265HPL, others say they can be replaced. Please help me.
    If you recommend a speaker, please put a link to purchase. I'm not in the US, I'm in Brazil where we didn't find anything about it.
    Thank you!

  11. #1676
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,170
    Quote Originally Posted by SilvioNovais View Post
    🟢Hello Friend! I'm quite confused about which speaker to use in my project.
    You commented on the 2216ndi, the original I believe is the 2265HPL, others say they can be replaced. Please help me.
    If you recommend a speaker, please put a link to purchase. I'm not in the US, I'm in Brazil where we didn't find anything about it.
    Thank you!
    2216nd is the driver used in the M2 already posted a link to purchase on the DIY forum.

    Rob
    "I could be arguing in my spare time"

  12. #1677
    Senior Member audiomagnate's Avatar
    Join Date
    Jan 2011
    Location
    Colorado and Georgia
    Posts
    1,022
    Quote Originally Posted by Robh3606 View Post
    2216nd is the driver used in the M2 already posted a link to purchase on the DIY forum.

    Rob
    Silly question. Does a perfectly set up M2, which I've never heard, do a a more realistic human voice than a 1400 Array? That's all I care about.

  13. #1678
    Senior Member edgewound's Avatar
    Join Date
    Jun 2005
    Location
    Southern California
    Posts
    2,776
    Quote Originally Posted by audiomagnate View Post
    Silly question. Does a perfectly set up M2, which I've never heard, do a a more realistic human voice than a 1400 Array? That's all I care about.
    Yes.
    Edgewound...JBL Pro Authorized...since 1988
    Upland Loudspeaker Service, Upland, CA

  14. #1679
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,170

    Post

    Quote Originally Posted by audiomagnate View Post
    Silly question. Does a perfectly set up M2, which I've never heard, do a a more realistic human voice than a 1400 Array? That's all I care about.
    I would try to find a pair to listen too. I have a pair if Be CC 1400's and a CC M2 based passive system. IMHO are not the same as far as imaging and depth. The 1400 is a bit more forward than the M2 passive. They are not in the same room and I know that the M2 is using 1dB of attenuation on the waveguide SO??? I wouldn't dump a pair of 1400's and go grab a pair of M2's without a good listen and preferably doing it side by side. The 1400 is a damn fine speaker on it's own account.

    Rob
    "I could be arguing in my spare time"

  15. #1680
    Member
    Join Date
    Dec 2016
    Location
    USA
    Posts
    48
    Quote Originally Posted by audiomagnate View Post
    Silly question. Does a perfectly set up M2, which I've never heard, do a a more realistic human voice than a 1400 Array? That's all I care about.
    The M2 being (intended to be) paired with the Crown amps using active crossovers, would be an apples-to-oranges comparison to the passive-crossover 1400.

    I feel that the better comparison would be the consumer / Synthesis version of the M2: the 4367. Comparing the 4367 to the 1400 I feel that the 4367 is a more accurate speaker.
    - Jeff

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. TAD MODEL-1 REFERENCE MONITOR
    By gerard in forum General Audio Discussion
    Replies: 30
    Last Post: 11-14-2014, 02:52 PM
  2. NAD Master Series
    By Domino in forum General Audio Discussion
    Replies: 6
    Last Post: 08-05-2008, 09:34 PM
  3. L100T/L100S as a reference/studio monitor
    By ldizac in forum Lansing Product General Information
    Replies: 16
    Last Post: 07-16-2006, 10:28 AM

Posting Permissions

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