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JBL MP255s vs. Cerwin Vega SL36B Earthquake

Discussion in 'Amps and Cabs [BG]' started by Phat Ham, May 8, 2003.


  1. Phat Ham

    Phat Ham

    Feb 13, 2000
    DC
    My friend is looking into buying a pair of subs for his PA, and right now the choice has boiled down to these two subs. The folded horn design of the Earthquake worries me a little, as I've heard it takes some distance for the sub to be heard, and most of the rooms these subs would be used in are relatively small. Anyone have experience with these subs?
     
  2. BruceWane

    BruceWane

    Oct 31, 2002
    Houston, TX
    A folded horn is audible up close, but the sound doesn't reach full volume until you are one wavelength away - and for bass frequencies, that's about 10-14 feet, depending on frequency. They are a lot more efficient than front-loaded cabs, though, so even up close they'll probably be around the same volume as a front-loaded cab driven by the same wattage.

    Unless it's a tiny room, the horns will be louder. And I would question your sanity if you're going to run a full blown PA in a 20' x 20' room.

    BUT, the JBL's will probably have better low end. Although Cerwin-Vega lists the 36B specs down to 30Hz, most soundmen will tell you that, on an analyzer, they roll off pretty sharply at about 50Hz. The common saying about the sound of the 36B is "it only plays one note, but it plays it very well".

    And the dimensions of the 36B horn do not support much frequency response below 45Hz. Horns for bass are complicated, strange, tricky things. They really work best in arrays of 3 or more.....when you put a number of them side by side, it extends the low frequency response, and this is really how these things are intended to be used. If you're planning on buying a pair and using 1 per side, I'd probably go with the JBL's, if price is roughly equal. If nothing else, the JBL's are probably smaller and lighter, and when you're talking about things that are in no way small or light, every bit helps.

    If you are planning on building up a nice PA, then maybe start with a pair of 36B's knowing that you're going to get some more of them, and a truck to move all of them, but if you just want a pair of subs for right now, I'd go with the JBL's.
     
  3. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    My ex-G/F owns and operates a PA system and has used a pair Cerwin Vega Earthquakes for years - one on each side in conjunction with a Mongoose style speaker for the mid-hoghs (ie 2x15's + a horn). They do indeed sound very nice for a single 18 but I think the top boxes overp;owered am a little. They take up a lot of space in the van, almost as much as a double 18 would with front loaded speakers. They do couple EXTREMELY well - meaning that with one on each side they do the job, but with 2 on each side, they defy the laws of physics and produce an incredible low end slam, especially for the kick drum. We did a tour opening for a well know band here in Australia and did 1000+ people rooms with 4 earthquakes - it sounded absolutely fantastic out front.
     
  4. BruceWane

    BruceWane

    Oct 31, 2002
    Houston, TX
    These are really too big for use as a bass guitar stage rig, but since we have some folks here who do some PA stuff as well....

    Tell ya what.........if you guys are interested in a state-of-the-art bass horn that you can build yourself for oh, roughly $450 or so, check out this site.......

    Lab Sub project at ProSoundWeb.com

    That link will take you to the last page.....the forum runs about 34 pages at this point. If you want to do this, you'll want to read the entire thing from the beginning. It starts with discussions of the basic design, and ends up with quite a few VERY happy soundmen. Lots and lots of tips on construction as these guys went through the process of building.

    The LabSub is a project undertaken by the distinguished Mr. Thomas Danley, the gentleman who designed the ServoDrive BT-7, considered by most to be the finest and most powerful subwoofer available at any price. It is a project he did for free, just because he's a really cool guy who enjoys sound and felt that it would be a good thing to give the little guys in the live sound biz a chance to compete with the big boys.

    Mr. Danley designed the horn cabinets and worked directly with Eminence to create the custom 12" drivers that the horns use. Each horn uses 2 12" drivers, which can be purchased at PartsExpress.com. About $150 a piece. 2 or 3 sheets of good plywood, plus glue and other stuff and you'll probably come in at $500 or less.

    These subs have been compared in a shootout with all the best and most popular subs in use by pro sound companies. They come up just short of the BT-7, but then BT-7's cost thousands......as far as ANY front-loaded subwoofer, the LabSub absolutely kicks their arse...........
     
  5. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    Absolutely. But from the original post, I got the impression the intended use was as PA subs.
     
  6. Phat Ham

    Phat Ham

    Feb 13, 2000
    DC
    Bruce and Pete, thanks for all the good info. These subs will be for PA use, and right now the plan is to get one per side, for a total of 2. Since the rooms we play are not all that big I can't see any realistic need for more than one per side. The advantage of the Earthquakes would be that they are 8 ohms, so they could be run in parallel to make a 4 ohm load and a single power amp could be bridged into them. The JBL's are 4 ohms each, so we'd either have to 1) get one power amp and run one of the JBL's off of each side or 2) get two smaller power amps and bridge each into a single JBL. In the end i guess it boils down to which one my friend thinks sounds better.
     
  7. BruceWane

    BruceWane

    Oct 31, 2002
    Houston, TX
    Thought I'd mention.........most of the guys that have built these things have said that they can use 2 Lab Subs in the place of eight 2x18" front loaded subs, volume-wise, AND they have much more low frequency response..........


    .......Also, if you want to learn A LOT about live sound in general, check out the rest of the ProSoundWeb site. Lots of good stuff there, lots of people who run sound for some very large outfits posting there on the live sound board, too.
     
  8. I was at a club last night (somewhat unusual, I don;t get out often ;-)
    anyway... they had a couple of tall Cerwin Vega horn enclosures as the PA. The 2 bands/artists I went to see fell into the experimental industrial /techno end of things -

    Anyway, I was suprised at how little real low bass was coming from the setup, it all seemed to be above 50-60hz at a guess and getting a bit mushy and 'grimy' sounding.

    I'm curious, what is a small band/performer to do when they want guaranteed earthquake rumble in a club with an average pa system, esp with music which requires this for impact? (other than build a labsub :) Obviously, I'm not talking about music for weddings here, but electronic music where ppl repsond well to big bass.

    Slighty off topic for this website I know, but dub reagge bassists must have same conundrum....
    this isn;t about being hideously loud, but getting that deep deep sound in a smallish performance area without having to haul around massive arrays... most of the subs I've checked out on websites on only specced down to about 40hz, despite being big enough to sleep in.
     
  9. BruceWane

    BruceWane

    Oct 31, 2002
    Houston, TX
    You have to strike a balance between volume and tone. There's no escaping the fact that you will need some subwoofers and that they ain't gonna be small, light things, but if you can live with a little less volume overall you can use that additional headroom to dial up extra lows with the eq.

    You know how it is.....you can get the most outrageously thick, rich tones out of your bass rig at home, at 100db, but try to get that same tone while producing 118db in order to hear yourself next to a caveman drummer and it becomes clear that somethings gotta give......you roll back on the low end enough to get the neccessary volume. And the less volume you need, the more you can crank the lows. Same goes for PA. Probably the biggest problem with PA in smaller rooms is that it has to compete with the band's stage volume. If you can keep this to a minimum, it really makes a huge difference. We all hate to hear it, believe me, I like it loud, too, but it's the truth. The only place that a Marshall stack on 11 and a drummer beating the life out of the skins will possibly sound OK is an arena.
     
  10. Good discussion, I like hearing PA stories and advice.:cool:

    I would recommend the JBL's for two reasons:

    1) Better resale. No, JBL isn't the last word in PA enclosures, but it's a name that more people lean to when buying used gear.

    2) It's less expensive to make 1200 watts per side into 4 ohms, more expensive to make 1200 watts per side into 8ohms. 1200 isn't the magic number for both of the cabs, but it's just for illustration purposes. It's very important to provide adequate power to PA enclosures and factor this into the overall cost, if you want to enjoy the potential of either sub.

    JMO
     
  11. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    That's easy. Hire a bigger PA. But the size of the PA is often governed by the budget, and both are often too small to generate the brute force you're talking about.

    I noticed at the "Homebake" concert this year that the Dance/Techno stage had a PA that was similar in size to the one on the main stage, despite being in a much smaller arena and playing to way fewer people. But they needed that Doof Doof to be slammin, so the wheeled in the extra subs.
     
  12. imani2k5

    imani2k5

    Nov 10, 2008
    Just reading over some remarks re: subs ..Right now i'm in the market for subs for DJ use (reggea,hip hop, dance music) - crowds range from 400-800 pp (looking for high impact as well as round low end)
    ...My choices are Cerwin Vega JE-36b folded horns (4), JTR Growler folded horns (4), Tuba 24 or 30 sub etc. Anyone got an idea which would be a good choice ?
    PS. Anybody heard of Decware WO sub (claiming 161 db SPL) ?
     
  13. 62bass

    62bass

    Apr 3, 2005
    I wish more young guys playing today would understand this. I hear a lot of the groups who would probably sound pretty good if they just cut the volume some and brought smaller amps to their gigs and let the soundman do his job.