+ Reply to Thread
Page 7 of 8 FirstFirst ... 5678 LastLast
Results 91 to 105 of 106

Thread: jbl 2245 H

  1. #91
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Destiny
    Posts
    7,515
    The aluminum shorting ring doesn't move at all it's burried under the gap. SFG magnet shorting ring not Dual Differential Drive, it works but helping to stabilize and make the flux equal on both sides of the gap top and bottom.

    Rob
    Attached Images Attached Images  
    "I could be arguing in my spare time"

  2. #92
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    837
    Quote Originally Posted by Robh3606 View Post
    The aluminum shorting ring doesn't move at all it's burried under the gap. SFG magnet shorting ring not Dual Differential Drive, it works but helping to stabilize and make the flux equal on both sides of the gap top and bottom.

    Rob
    Interesting reading about the influence of the "short ring"
    http://diy-audio.narod.ru/litr/Farad...lImpedance.pdf

  3. #93
    Member
    Join Date
    Sep 2011
    Location
    SC
    Posts
    61
    Quote Originally Posted by Robh3606 View Post
    The aluminum shorting ring doesn't move at all it's burried under the gap. SFG magnet shorting ring not Dual Differential Drive, it works but helping to stabilize and make the flux equal on both sides of the gap top and bottom.

    Rob
    That's the construction on newer drivers, not the 2245. How could there be rubbing marks on the aluminum ring on my old 2245 if it did not move with the voice coil? Believe me, it moves. Maybe it's incorrect to call it a shorting ring but I don't know what else to call it.

  4. #94
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Destiny
    Posts
    7,515
    That's the construction on newer drivers, not the 2245.
    It doesn't matter. The aluminum flux ring is in the same location. Have a read of the attached link

    http://www.audioheritage.org/vbullet...ume-1-Number-9

    How could there be rubbing marks on the aluminum ring on my old 2245 if it did not move with the voice coil?
    Without the outer foam ring the whole cone tilts and rubs. The rub marks could easilly be from the former rubbing against the top plate and pole piece. The aluminum you can see is part of the VC form not the stabilization ring. The voice coil form obviously moves.

    Rob
    Attached Images Attached Images  
    "I could be arguing in my spare time"

  5. #95
    Senior Member Eaulive's Avatar
    Join Date
    Aug 2009
    Location
    Back in Montreal
    Posts
    1,197
    Quote Originally Posted by dr_gallup View Post
    That's the construction on newer drivers, not the 2245. How could there be rubbing marks on the aluminum ring on my old 2245 if it did not move with the voice coil? Believe me, it moves. Maybe it's incorrect to call it a shorting ring but I don't know what else to call it.
    That's where the misunderstanding comes from, the part that has the rubbing marks is not the shorting ring, it's the voice coil former, so of course it moves

    The shorting ring is deep into the magnet structure and is fixed, coincidentally your VC former is also made of aluminum, that's the confusion
    My avatar: 4520 loaded with 2225H on E140 frames,
    1x B&C 12PE32 on custom front loaded horn, 2x 2426 on 2370.

  6. #96
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    837
    Quote Originally Posted by dr_gallup View Post
    That's the construction on newer drivers, not the 2245. How could there be rubbing marks on the aluminum ring on my old 2245 if it did not move with the voice coil? Believe me, it moves. Maybe it's incorrect to call it a shorting ring but I don't know what else to call it.
    As seen from E120 technical data
    http://www.audioheritage.org/vbullet...l=1#post148781
    there is seems some kind of aluminum foil in the former, I expect mainly to reduce coil inductivity (Le) that would become of importance on higher frequency (over 1kHz), but concerning that 2245 is LF driver, such aluminum former had mechanical and electrical "purpose",
    but on the figure of 2245 cone kit aluminum foil is not visible
    Attached Images Attached Images    

  7. #97
    Member
    Join Date
    Sep 2011
    Location
    SC
    Posts
    61
    Quote Originally Posted by Robh3606 View Post
    It doesn't matter. The aluminum flux ring is in the same location. Have a read of the attached link

    http://www.audioheritage.org/vbullet...ume-1-Number-9



    Without the outer foam ring the whole cone tilts and rubs. The rub marks could easilly be from the former rubbing against the top plate and pole piece. The aluminum you can see is part of the VC form not the stabilization ring. The voice coil form obviously moves.

    Rob
    Thanks for that link, it really explains what's going on.

  8. #98
    Moderator / Treasurer/Marketplace Czar boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    6,906

    2245h

    Revisiting an old thread...

    In the past few months, the response of the 2245H's in my 4345's (stock) seem to have improved subtly, yet wonderfully. I've not changed a thing in my system for a number of years; and, I'm not a heavy user, being as I'm frequently out on tour. So, maybe this "extended break-in" is just that. Whatever it is, their tonality is ever-more remarkable.

    We had dinner guests last night, and after all the social folderol, we got down to some serious listening. My neighbors had never heard such things as what the 2245H's produce - they left carrying their jaws. And, it was at maybe 75dB.

    Just sayin'...
    bo

    "Indeed, not!!"

  9. #99
    Senior Member BMWCCA's Avatar
    Join Date
    Feb 2006
    Location
    Virginia
    Posts
    5,555
    Quote Originally Posted by boputnam View Post
    Revisiting an old thread...
    they left carrying their jaws. And, it was at maybe 75dB.

    Just sayin'...
    Nice to see your name on a post.

    Sweetness happens.

    Count your blessings!
    ". . . as you have no doubt noticed, no one told the 4345 that it can't work correctly so it does anyway."—Greg Timbers

  10. #100
    Senior Member Ian Mackenzie's Avatar
    Join Date
    Apr 2003
    Location
    The Tardis
    Posts
    5,952
    Quote Originally Posted by boputnam View Post
    Revisiting an old thread...

    In the past few months, the response of the 2245H's in my 4345's (stock) seem to have improved subtly, yet wonderfully. I've not changed a thing in my system for a number of years; and, I'm not a heavy user, being as I'm frequently out on tour. So, maybe this "extended break-in" is just that. Whatever it is, their tonality is ever-more remarkable.

    We had dinner guests last night, and after all the social folderol, we got down to some serious listening. My neighbors had never heard such things as what the 2245H's produce - they left carrying their jaws. And, it was at maybe 75dB.

    Just sayin'...
    I think you had the same experience when you first heard them at Ken's place mate.

    How about a recent pic.

    Ian

  11. #101
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    837
    Quote Originally Posted by boputnam View Post
    Revisiting an old thread...

    In the past few months, the response of the 2245H's in my 4345's (stock) seem to have improved subtly, yet wonderfully. I've not changed a thing in my system for a number of years; and, I'm not a heavy user, being as I'm frequently out on tour. So, maybe this "extended break-in" is just that. Whatever it is, their tonality is ever-more remarkable.

    We had dinner guests last night, and after all the social folderol, we got down to some serious listening. My neighbors had never heard such things as what the 2245H's produce - they left carrying their jaws. And, it was at maybe 75dB.

    Just sayin'...
    I am afraid that "refoamimg 2245" would become soon, so be care not to destroy inner parts. I have almost the same experience with my 2231A drivers. Unfortunately there are no original refoam-kit for either 2245 or 2231 drivers. Most of the AF refoams do not sound as previous originals. Another problem: even the recon-kits do not sounds as originals....

  12. #102
    Moderator / Treasurer/Marketplace Czar boputnam's Avatar
    Join Date
    Apr 2003
    Location
    northern california
    Posts
    6,906
    Quote Originally Posted by Ian Mackenzie View Post
    I think you had the same experience when you first heard them at Ken's place mate.


    Quote Originally Posted by Ian Mackenzie View Post
    How about a recent pic.
    Can do - but I'm headed off for a few days, so on my return. Not much has changed - I must have found a really nice high plateau...
    bo

    "Indeed, not!!"

  13. #103
    Member
    Join Date
    Mar 2010
    Location
    Saint-Roch-de-l'Achigan
    Posts
    96
    Quote Originally Posted by dr_gallup View Post
    That's the construction on newer drivers, not the 2245. How could there be rubbing marks on the aluminum ring on my old 2245 if it did not move with the voice coil? Believe me, it moves. Maybe it's incorrect to call it a shorting ring but I don't know what else to call it.
    From what I had in the past: two 12 inches that I did buy (cheap) but I hat to recone them (myself) with original parts from JBL. They had a Mass Ring, JBL did that for their studio woofers so the mass ring reduces efficiency a lot but makes the woofer going much lower than let's say a K-120 (guitar speaker). That mass ring was glued to the inner side of the voice coil, near the dustcap.

    Hope that it gives you some light

  14. #104
    Member
    Join Date
    May 2007
    Location
    Bakersfield, CA
    Posts
    82

    Reconing the JBL 2245H

    I know that it is considered blasphemy here to consider such things but ...

    Since JBL is no longer offering kits to rebuild the 2245H driver, does anyone here have first hand experience with the McKenzie kits? Assuming that a JBL kit is not available who is the preferred fallback vendor?

    http://reconekits.com/jbl2245h8ohmreconekit.aspx
    _____________
    Best Regards,
    Carl Huff

  15. #105
    Obviously... not a golfer grumpy's Avatar
    Join Date
    Oct 2003
    Location
    SoCal
    Posts
    4,188
    JBL is no longer offering kits to rebuild the 2245H
    Is that, in fact, true? C8R2245H seems to -not- be NLA ($276 as of April 26)
    It's uh... uh... it's down there somewhere, let me take another look...

+ Reply to Thread

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. JBL 2245 Ideal enclosure
    By Niklas Nord in forum Lansing Product Technical Help
    Replies: 31
    Last Post: 07-29-2014, 04:25 PM
  2. Altec 825-828 cab with built in JBL 2245 subwoof
    By Roland in forum Lansing Product General Information
    Replies: 4
    Last Post: 06-23-2003, 04:39 PM
  3. JBL 2245 and Passive Radiator
    By Niklas Nord in forum Lansing Product DIY Forum
    Replies: 1
    Last Post: 04-29-2003, 06:51 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