1. Welcome to TalkBass, the Premier Bass Player Community and Information Source. We've been uniting the Low End Since 1998!

    We're glad you've found us. Register a 100% Free Account to post and unlock tons of features.

JBL E-140 content/ ongoing DIY 215 project

Discussion in 'Amps [BG]' started by wighat, Sep 25, 2013.


  1. wighat

    wighat

    Joined:
    Apr 27, 2005
    Location:
    Port Aransas, Texas
    I've started a couple of threads about my Ampeg V4B and DIY 215 project but I'm switching tracks on the cab now, so here goes another.

    Modeled and built a box around the MCM 2983 driver. Got the tuning right, and it sounded OK, but I wasn't happy with the mids and certainly not with the efficiency.

    New design parameters:

    215, don't care about size or weight (within reason)

    5-string friendly with some action below 40Hz, preferably usable down to 31 Hz

    Old-school tone and appearance to go with the V4B

    Enough efficiency to make this cab/head combo a viable alternative to my SVT/410 rig

    Almost danced a jig when I came across the spec's to the (discontinued, I know) E-140! Fs of 32 Hz, 100dB sensitivity and (unfortunately) a whopping 10.5 cu ft Vas. Aluminum dust cap and, according to many, among the best-sounding speakers for bass guitar.

    So, if I tune a 6 cu ft chamber for each driver at 35Hz, I'll get a -10 dB point of 31 Hz. I don't think my V4B is going to be getting much over 150 watts (correct me if I'm wrong). Excursion is safe up to that figure.

    Anybody got any comments, criticisms, etc?
     
  2. 4Mal

    4Mal Supporting Member

    Joined:
    Jun 2, 2002
    Location:
    Columbia River Gorge
    That all sounds highly optomistic ... Good luck with it though.
     
  3. Stumbo

    Stumbo Wherever you go, there you are.

    Joined:
    Feb 11, 2008
    Location:
    Los Angeles
    PM JBl guru JohnK_10.
     
  4. wighat

    wighat

    Joined:
    Apr 27, 2005
    Location:
    Port Aransas, Texas
    I would be pleased to hear why.
     
  5. Register to disable this ad
  6. jnewmark

    jnewmark Supporting Member

    Joined:
    Aug 31, 2006
    Location:
    Stax 1966
    Disclosures:
    Play guitar.
    Go for it ! here's my LDS built 215 with JBL's.
     

    Attached Files:

    • 215.jpg
      215.jpg
      File size:
      7 KB
      Views:
      364
  7. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    A more manageable 4 cu.ft. box with those same JBL's will give you a much more practical, and just as good sounding a rig, seeing as your V4B doesn't have anywhere near enough juice to push 31hz audibly in comparison with the rest of the bandwidth and its output transformer would limit it's ability to do so, even if you added another zero on the end of its watt rating.


    In other words, the boxes would sound just as good, if not more so, and you'd actually be able to fit them in your car.....meaning you could take them places and play them for other people to hear. :D
     
  8. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    I'm saying something approaching 4 cu.ft per driver, not for both. If I mis-understood that, ignore what I said earlier and continue on with what you're doing....sorry.
     
  9. wighat

    wighat

    Joined:
    Apr 27, 2005
    Location:
    Port Aransas, Texas
    There isn't any inherent reason my amp can't do the 30's. Got plenty beefy transformers and I've done quite a few listening tests by both sine wave and bass. Anyway, cab design is one of the few factors I can control. Fat strings help, too.
     
  10. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    It may be a hifi design with big transformer and fat strings, but it still doesn't have the juice to push 30hz "loud enough to matter" in comparison to the rest of the bandwidth.

    Yes, you need some response that deep, and it may have it, but you don't need response even with the rest of the bandwidth down there, which is a good thing, because it would severly limit how loud you could go with the rest of the bandwidth.



    It's a V4 and JBL's....pretty hard to make sound bad. I'm just advising against fridge size boxes with one speaker each when something more manageble would sound just as good. 100 watts, no matter how badass those particular 100 watts are, isn't going to put out 30hz that can be heard audibly in a typical bar/club full of bodies...at least not at any level that matters.
     
  11. Vince Klortho

    Vince Klortho

    Joined:
    Jan 8, 2013
    Location:
    Squierville, California
    One problem you might have is SPL. The E140 is rated for 200W and they might not get loud enough for you in the extreme low end.

    Good luck with it. I will be interested to know how it turns out.
     
  12. wighat

    wighat

    Joined:
    Apr 27, 2005
    Location:
    Port Aransas, Texas
    For sure. I'm thinking one fairly large-ish 215 that will be a standard bass cab with a touch of low extension.
     
  13. nashvillebill

    nashvillebill

    Joined:
    Oct 13, 2002
    Location:
    Nashville TN
    JBL's Enclosure Guide recommends an 8.0 cu ft enclosure for a pair of E140's. Tuned to 40 hz, (4) 4.0 inch ducts at 5.0 inches long.
     
  14. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    OK....4 cu.ft. per driver then.
     
  15. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    Really, 4 cu.ft. per driver is a sort of sweetspot for a deep, ballsy 15" bass rig one can still take places/do something with. Sure, you can go bigger, and get "hifi" sort of range.....in something that is low power handling for live use and turns into a bigger PITA to haul around than sub bins are....to very little benefit, and possibly some detriment, for the listening public in a typical, direct radiator alignment.

    It just works. You can shrink it some and lose very little, at least at first.

    Or you can embiggen <---(I love that word) quite a lot, gain very little and lose more.

    Caveat: for use in projecting live sound, bass musical stringed instruments.....nothing to do with high fidelity, pre-recorded music playback listening or electronic blip-n-bleep so-called "music" kids make on laptop computers.
     
  16. taurus1

    taurus1

    Joined:
    Sep 13, 2006
    Location:
    Vancouver B.C.
    I have a couple E-140's in an old Acoustic cab, I like it.
    I've always wanted a 2x15 cab the same dimensions as my Marshall 4x12, so I can stack it and have it match, purely aesthetics.
    that would have to be a pretty deep 4x12ish size cab to get 8 sq. feet I'm thinking.
    anyone have a rough idea?
     
  17. will33

    will33

    Joined:
    May 22, 2006
    Location:
    austin,tx
    Disclosures:
    Use of this field for any other purpose is prohibited
    26" x 26" external face times whatever depth to reach 8 cu.ft. allowing panel thickness, etc.?

    If done right, you'd hear little if any difference between there and 7.33 cu.ft.
     
  18. Vince Klortho

    Vince Klortho

    Joined:
    Jan 8, 2013
    Location:
    Squierville, California
    The Marshall is about a 26x26 inch cabinet so the 2x15 cabinet will have to be about 2 feet deep to have a volume of 8 ft[SUP]3[/SUP].
     
  19. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Location:
    New Zealand
    What are the stats on that badboy?
     
  20. wighat

    wighat

    Joined:
    Apr 27, 2005
    Location:
    Port Aransas, Texas
    This rig will certainly not be hi-fi!

    Again, just want a little lower capability out of this cab and I don't mind it being fully fridge-sized. I understand that the larger enclosure and lower tuning will diminish the power handling somewhat but I don't need it to handle that much -I'm keeping my eye on excursion. Also, these drivers are said to be very conservatively rated.

    I can't think of any other negatives to this design, will33, but hearing them is why I posted, so thank you.
     
  21. CL400Peavey

    CL400Peavey Supporting Member

    Joined:
    Nov 7, 2011
    Location:
    Grand Rapids Michigan
    Do you already own the drivers? If not I would take a serious look at the greenboy Dually loaded with the 15PR400's. Or if you are building your own cab take a look at JohnK's starliner with the same drivers. In either case you can have the cab finished how ever you want.

    I love my Ampeg amp with my DuallyT.
     

Share This Page