Page 1 of 2 12 LastLast
Results 1 to 15 of 16

Thread: Possible " 3 - Way " :

  1. #1
    David V. Webber
    Guest

    Possible " 3 - Way " :

    I have a pair of " Bookshelf " Speakers I made using JBL components .
    LE85 Mid / High , [ Potato Masher Lens ; will accept gift of Slant - Plate
    Lens , ] LE14 Woofer with LX7 crossover . Just saved - up the $ 600
    to replace the two blown LE85 diapragms . Woofers just re - foamed .

    If I were to add a JBL Slot Radiator to the " mix " , what sort of a
    " High - Pass " would I need ? Just a Cap , or a coil also ? I am 75 , so
    if it is a little brighter , skipping any Resistor would probably be Okay .

    The diagram of the original LX7 is on this site . However , Mr. Greg Timbers sent me a complete set of parts to build a new pair , FREE , with a pair of GIGANTIC Air Coils ! His " new " LX7 is " modern " , and perhaps differs slightly from the original . If you need that info , I can send you a
    picture of that diagram .

    Just missed a pair of Slot Radiators on Ebay ; ( but , perhaps , they had been " stressed " !!?? )

    DAVID V. WEBBER

    610 - 793 - 1129

  2. #2
    Senior Member jcrobso's Avatar
    Join Date
    Oct 2008
    Location
    Chicago
    Posts
    1,099

    Some pictures would be nice.

    Quote Originally Posted by David V. Webber View Post
    I have a pair of " Bookshelf " Speakers I made using JBL components .
    LE85 Mid / High , [ Potato Masher Lens ; will accept gift of Slant - Plate
    Lens , ] LE14 Woofer with LX7 crossover . Just saved - up the $ 600
    to replace the two blown LE85 diapragms . Woofers just re - foamed .

    If I were to add a JBL Slot Radiator to the " mix " , what sort of a
    " High - Pass " would I need ? Just a Cap , or a coil also ? I am 75 , so
    if it is a little brighter , skipping any Resistor would probably be Okay .

    The diagram of the original LX7 is on this site . However , Mr. Greg Timbers sent me a complete set of parts to build a new pair , FREE , with a pair of GIGANTIC Air Coils ! His " new " LX7 is " modern " , and perhaps differs slightly from the original . If you need that info , I can send you a
    picture of that diagram .

    Just missed a pair of Slot Radiators on Ebay ; ( but , perhaps , they had been " stressed " !!?? )

    DAVID V. WEBBER

    610 - 793 - 1129
    This way we can see what your doing.

  3. #3
    David V. Webber
    Guest

    Pictures :

    I scanned all the stuff from Greg Timbers . The scanner sent it all to the Computer . I've looked through hundreds and hundres of Documents /
    Pictures with no luck . I DO have a FAX . OR , [ I am in no rush , I have two crossovers to build ! ] , I can slip them in an envelope and send them " Snai Mail " .

    My E - Mail address is :

    DaveSail - at - AOL . Com

  4. #4
    Unabashed Speakerholic cosmos's Avatar
    Join Date
    May 2007
    Location
    Ohio
    Posts
    296
    Best would be to use a 3105 (N7000 7000 Hz crossover) or 3106 (N8000 8000 Hz crossover) for the 2405/077 slot ring radiator.

    You can download both the 3105 ( N7000 ) & the 3106 ( N8000 ) schematics from JBL at crossover schematics .

    That said, the LE85 goes up high enough that most would say they don't need a tweeter. It's a great driver. Further, At 75, if you can hear higher than a LE85 goes, I want to have your hearing and I am only 52...

    Also, a little recommendation would be to go back and erase your e-mail address. It will get picked up by programs scouring the web in search of e-mail addresses and the amount of junk e-mails you get will go up.. You can safely say that your email address is "DaveSail - at - AOL.com" and humans will interpret it correctly..

    Best regards.

  5. #5
    David V. Webber
    Guest

    Crossover Help :

    Thank you for the proper crossovers . Are any still made , or would I have to build my own ?

    I don't listen to loud rock with " Thumpers " in my car trunk , so my ears are pretty good . At one of those , ( actually , two , ) Speaker Builder
    meetings in Virginia , one guy had a device that played a sampling of all the frequencies up to and well beyond 20,000 Hz. Of course , it is a matter of volume and distance from the source ; ( fades as the square of the distance . ) I was sitting in the front row , and I'm certain I could hear at least the 22,000 Hz . [ My left ear is a BIT off from the right , due to terminating a Deer out front who used a Mercedes to commit suicide . I used my Colt Python , with a .357 Magnum round , and NO ear - plugs or muffs ! That rang for awhile ! David V. Webber

  6. #6
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    9,720
    Quote Originally Posted by David V. Webber View Post
    I don't listen to loud rock with " Thumpers " in my car trunk , so my ears are pretty good . At one of those , ( actually , two , ) Speaker Builder meetings in Virginia , one guy had a device that played a sampling of all the frequencies up to and well beyond 20,000 Hz. Of course , it is a matter of volume and distance from the source ; ( fades as the square of the distance . ) I was sitting in the front row , and I'm certain I could hear at least the 22,000 Hz .
    That puts you firmly in the freak of nature category... congratulations. Even in High School, I topped out around 18KHz... and don't even get close to that today.

    Assuming you are hearing above 15KHz, you owe it to your fine hearing to definitely use a pair of proper tweeters. 077/2405s would be my choice if sticking with vintage JBL.


    Widget

  7. #7
    Senior Member
    Join Date
    Mar 2007
    Location
    Los Angeles, Calif USA
    Posts
    183
    Quote Originally Posted by David V. Webber View Post
    .
    .
    I used my Colt Python , with a .357 Magnum round , and NO ear - plugs or muffs ! That rang for awhile ! David V. Webber
    Wow, that is loud really loud even with ear muffs and a foam plugs together.

    Personally, I would add a super tweeter to the mix because I like the sound better. I think JBL's factory passive crossover for the 077 was at 7KHz.

  8. #8
    Senior Member Doc Mark's Avatar
    Join Date
    May 2008
    Location
    Southern, California, USA
    Posts
    1,371
    Quote Originally Posted by RKLee View Post
    Wow, that is loud really loud even with ear muffs and a foam plugs together.

    Personally, I would add a super tweeter to the mix because I like the sound better. I think JBL's factory passive crossover for the 077 was at 7KHz.
    Morning,

    Yes, JBL did use a 7khz crossover point for the 077, but I must add that the 077/2405 sounds a bit harsh when crossed over that low. That wonderful tweeter really comes into it's own when crossed a bit higher. I'd go no lower than 8khz, and might even go up higher, say to 10khz, for best results. My first 2405 came with the JBL 3105 crossover, which is set for 7khz. To my ears, the tweeter sounded a bit harsh, brittle, and edgy with that crossover. Later, I experimented with higher crossover points, using my old Crown VFX-2A electronic crossover, and I was very impressed by how the 077/2405 opened up and smoothed out it's performance. For what it's worth.... Take care, and God Bless!

    Every Good Wish,
    Doc
    The only thing that can never be taken away from you, is your honor. Cherish it, in yourself, and in others.

  9. #9
    Senior Member
    Join Date
    Jan 2005
    Location
    Detroit
    Posts
    391

    3105 vs 3106

    Quote Originally Posted by Doc Mark View Post
    Morning,

    Yes, JBL did use a 7khz crossover point for the 077, but I must add that the 077/2405 sounds a bit harsh when crossed over that low. That wonderful tweeter really comes into it's own when crossed a bit higher. I'd go no lower than 8khz, and might even go up higher, say to 10khz, for best results. My first 2405 came with the JBL 3105 crossover, which is set for 7khz. To my ears, the tweeter sounded a bit harsh, brittle, and edgy with that crossover. Later, I experimented with higher crossover points, using my old Crown VFX-2A electronic crossover, and I was very impressed by how the 077/2405 opened up and smoothed out it's performance. For what it's worth.... Take care, and God Bless!

    Every Good Wish,
    Doc
    Hi Doc - Yes, on the money, been there done that. And, if you look at the JBL schematics, you will see that the 3105 actually crosses (LF= -3db, HF= -3db) at 5kHz! As Doc says, too low for the 077; sounds harsh, etc. It's the 3106 that is more reasonable for the 077 crossing at 7kHz. Plus, it has a 20 ohm pad on the low frequency horn which is usually desirable. But, what I, and I'm sure others, did is wire up my own version of the 3106 and tweak per my ear/room, et al. Always seem to end up with a 1 mF cap and .3 mH coil plus L pad adjusted as necessary (I wire it up fixed). And, of course, it never ends!

  10. #10
    David V. Webber
    Guest

    High Pass Filter :

    Is the Cap in series on the " + " side and the coil across , ( before or after the Cap ) ? David V. Webber

  11. #11
    Senior Member
    Join Date
    May 2008
    Location
    Westchester NY
    Posts
    1,120
    I ran the 077 slots with the n7000 crossovers in a home system for about 25 years and I never thought they were edgie or harsh but crossing these higher is probably not a bad idea.

    If you are considering this I would look at the JBL 2405 slots in ceramic motors since they are a lot less expensive than the 077 or 2405 alnico drivers. ...just make sure you are using JBL OEM diaphragms.

    Avoid e-bay, if possible.

  12. #12
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,597
    As a better alternative to the simple 1.5 mfd cap/0.3 mH coil in the 3106. You may find that the circuit used in the 4433 to sound better. It retains the same cap/coil as the 3106 on the mid but adds a 1 mfd cap before the coil and the coil is reduced to 0.16 mH on the tweeter.

    The 075 and its variants have a dip in the 8-9kHz range to varying degrees, and best I can figure, the second cap creates a peak that is to fill this dip in the 2405/077.

  13. #13
    Senior Member
    Join Date
    May 2007
    Location
    Ingolstadt in Germany
    Posts
    456

    probably an artifact

    Quote Originally Posted by David V. Webber View Post
    ..., one guy had a device that played a sampling of all the frequencies up to and well beyond 20,000 Hz. Of course , it is a matter of volume and distance from the source ; ( fades as the square of the distance . ) I was sitting in the front row , and I'm certain I could hear at least the 22,000 Hz .
    One would need to know how the guy sampled the signals and how he played them back before one could explain what has happened.

    If the sampling frequency is too low for the signal beeing sampled (if the Shannon theorem is violated) You will not sample and play back silence but rather some audible artifacts. Your ears will hear ***something*** but that will not be 22 kHz.

    Ruediger

  14. #14
    Senior Member
    Join Date
    Jan 2005
    Location
    Detroit
    Posts
    391
    Quote Originally Posted by David V. Webber View Post
    Is the Cap in series on the " + " side and the coil across , ( before or after the Cap ) ? David V. Webber
    Yep, the cap is in series "+", coil parallel. You can also try the cap alone (first order filter) as you mentioned above and then "clip in" the coil (after the cap) with alligators soldered to the coil leads. Basically follow the JBL schematic. An old text I like is, Hi-Fi Loudspeakers and Enclosures by A.B. Cohen. It's an oldie based on fundamental math and physics - excellent basic learning tool for hobbists. Lots of examples. Remember, "One test is worth 1000 expert opinions!" Have fun.

  15. #15
    David V. Webber
    Guest

    077 Slots / Ceramic Motors :

    Quote Originally Posted by robertbartsch View Post
    I ran the 077 slots with the n7000 crossovers in a home system for about 25 years and I never thought they were edgie or harsh but crossing these higher is probably not a bad idea.

    If you are considering this I would look at the JBL 2405 slots in ceramic motors since they are a lot less expensive than the 077 or 2405 alnico drivers. ...just make sure you are using JBL OEM diaphragms.

    Avoid e-bay, if possible.
    Who sells the Ceramic ones ? Is the sound different in any way from theAlnico ? Or the Power Handling , etc. ?

Thread Information

Users Browsing this Thread

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

Posting Permissions

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