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Beyma 12BR70 plus ??Mid?? plus JBL 2404H to compete with JBL 100 re-issue?

Hello all:  Thought I'd start a new thread since I screwed up in my introductory post.  I have a nice old pair of EV Marquis speakers with beautiful cabinets that I'd like to re-purpose for my workshop, or even the first floor of our Mid Century modern house.  My intent is to compete with the sound I hear from the new JBL 100 re-issues at $4000 list. The EV cabinets have an interior volume of 3.4cf.  (interior is 17.5'w by 13"d x 26.5"H) The back 3/4 ply has (4) 1/4" x 10" long slot vents, which I assume I will simply replace, or build over-top.

I have NIB JBL 2404H for tweeters. 

Am looking at the Beyma 12BR70 for a woofer, ($126 each from US Speaker) and need recommendations for a mid to pair up with that to work with a high crossover point for the 2404.   I was looking at the Beyma 6MI90 mid today, at about $120 each.  JBL has used the 2404H as low as 3500khz, but normally it is recommended to cross higher, like 5khz.  The EV cabinet is pretty wide old-school, being 19" on the outside.  I could theoretically fit a 15" in there too, if it will work with the cabinet volume. The 2404H can sit on top if needed, but prefer to have the woofer and mid inside the existing cabinet.  No subwoofers desired, and a minimum overall output at 90db with 1 watt.

In my introductory comments, I mentioned I have no idea of how to build crossovers.  I do have an active stereo 3 way CDM crossover I can use to try out ideas, but in the end would really appreciate help building a passive crossover.

Any comments or suggestions?


Comments

  • Zero interest in this idea?  No love for Beyma 12BR70?  Not fans of JBL butt cheeks?  Would sure appreciate some opinions here.....
  • I would double check the volume requirements for Beyma 12BR70.  I would also look at DIY Soundgroups magnum 12. Apart from expensive Acoustic Elegance woofers, it seemed to be the best fit for a balance between hifi low end capability and pro efficiency.  Ciare HW321 is another woofer worth considering.
  • e6zion:  from what I've read, 2-4 cf sealed, well stuffed seems to be the recommendation.  The enclosure I have is 3.14 cf not subtracting for woofer volume.  I like AE woofers quite a bit, but saw a project where they used the Beyma to good effect, and they are much cheaper and readily available.  I don't want to pour a ton of money into these, for workshop speakers.

    I'll look into your other recommendations. Thank you!
  • e6zion: took a look at the Magnum 12.  That is a very good option, and Erich's suggestions for box size make it a perfect fit for this project.  Now to find a nice mid to fit between that and the JBL at about 4500hz.  Another option might be one of the SEOS units.

    Thanks for the suggestion.
  • What size mid are you looking to integrate?
  • edited March 2019
    My current build is open back speakers with twin 12BR70s (designed top-end to be interchangeable; celestion 6.5s coax's, Audio Nirvana super 6.5's, or... Crossing at ~ 240Hz from W's), in any event, I'm a fan of the BR's.  Not dealing with a box of course, but they take a low shelf boost to offset the dipole set-up without complaining...

    & those JBL's tweets are keepers


  • OscarJr:  I was thinking something around 5-6.5 inch. So far, in my very limited viewing, the Satoris look very nice, but are much less efficient than the woofer or tweeter.  I'd prefer to run the JBL's at closer to 5500hz, or even higher.

    I question whether this exercise is worth the trouble, vs just buying different drivers.  But, I never seem to be able to sell things off I'm not using, and the JBLs' are here.  And, I like the sound of them. 

    I was shocked when I took the back off those speakers today.  I knew that they had the alnico magnet SP12 woofers, but for some reason I thought they had the T35 tweeters.  They have T25A midrange units.  So, the horrible upper frequencies I'm hearing are either due to the compression driver, or possibly the crossover.  (?)  The T25 are not very well thought of.  I'm thinking of getting out my TDM 3 way crossover, and mounting the JBL's in a small chunk of plywood, and just run the woofer up to 4500 with a 24db per octave crossover.  Just to see how they sound.  The EV woofers are run far beyond that in some applications, however, I have no idea how they sound. 

    Right now, the woofers sound good, but no serious punch.  The upper freq are horrid.  before replacing the woofer, I want to see how it fares with the crossover and mid compression unit out of the picture.


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