18" speaker without a crossover

Discussion in 'Amps and Cabs [BG]' started by Tiny Tim, Aug 8, 2005.

  1. Tiny Tim

    Tiny Tim

    Jul 8, 2002
    Salem, Oregon
    I need to replace a 18" speaker in my carvin cabnet and am wondering if I get a speaker with only 25hz- 500hz responce will it damage the speaker to run full range with my 410 as I had in the past? I am looking for a speaker with high x-max but most have reduced frequency responce. or is there a low pass filter I could get to protect the speaker that I could put in the cabnet? thanks for your help. Tim
  2. Kelly Lee

    Kelly Lee Yeah, I'm a guy! Supporting Member

    Feb 17, 2004
    Marana, AZ, USA
    Normally its lower frequencies that are more destructive to a driver rather than higher. IME, you should be fine.

    The one thing to note is once you get out of the drivers freq. range it will start to roll off pretty quick. So if your driver goes up to 500hz as stated by the manufacturer, thats it's 3db down point and as frequencies get higher they will become less audible.

    One question though, why do you want to increase your Xmax at the expense of frequency response? :confused:
  3. Tiny Tim

    Tiny Tim

    Jul 8, 2002
    Salem, Oregon
    I am looking for a speaker that will survive down tuning and loudness. I don't know that much about speaker design but what I have gathered x-max is the key for low bass and speaker life? I would like any help or recommendations for raw speakers in the $150-300 range, and any education anyone could add. Tim
  4. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    No no no. Xmax is but ONE facet of low end response and speaker life. CABINET TUNING is just as important, and if you stick any other speaker in there, you have to compute and adjust the port tuning to compensate. If you don't, you can not only get overexcursion, but premature "farting" of low notes.

    If you can find an 18 with identical TS parameters as your existing 18, but with better xmax, that will help. But it is very, very unlikely you will be able to.
  5. Kelly Lee

    Kelly Lee Yeah, I'm a guy! Supporting Member

    Feb 17, 2004
    Marana, AZ, USA
    There is alot more to it than just Xmax that makes a speaker/enclosure combo handle really low frequencies at high volume.

    First, lets get some more info.

    What tuning(s) are you using?
    What amp and current cab(s) are you using?
    What type of music do you play?
    What is your current Carvin cab doing that you need to change the driver?
  6. Tiny Tim

    Tiny Tim

    Jul 8, 2002
    Salem, Oregon
    Thanks guys for your help so far!
    I am using a SWR SM900 head bridged mono 900 watts at 4 ohm running into an Avatar 410 8ohm and the Carvin 18 8ohm cabnet. the speaker in the Carvin is distorting very baddly 1/8 volume and intermittant not working at all, it is an older version and I bought it used. Tuning is mostly low B or up to C but I like a very full low sound; which the avatar can't do alone; playing very loud Heavy Metal.
  7. Kelly Lee

    Kelly Lee Yeah, I'm a guy! Supporting Member

    Feb 17, 2004
    Marana, AZ, USA
    Hmm, have you checked to make sure the connections inside the cab are good? Could be a loose wire or one about ready to break.

    If its not a wire, the driver is bad. I would either buy a replacement driver from Carvin or you will have to try and find one that will match your cab pretty close.

    Go to Linear Team and download WinISD or use their online version. Get the Thiele-Small parameters from Carvin here:Carvin Driver Specs
    Now, go to Eminence or anyone else that offers an 18 and find a driver that fits the bill as close as possible to what the Carvin specs out for an enclosure. Remember, port lengths can be changed to get the right port volume.


    Nov 24, 2001
    New York,NY
    ...man...I'm beyond words here...DUDE...you're talkin' about an 18...what the HELL do you care about a crossover for???

    ESPECIALLY in a "heavymetal band"...You have a an "eq" right???...

    You tune to"B-C"...whoopeedoo, you'll NEVER have to worry about going TOO high or low with basically ANY 18 in that range, believe me...

    Also, what are you looking to spend in your whole rig??? Everything counts & sound usally = $$$...


    PS: Honestly, if it's a "Death Metal/Speed" type deal, I wouldn't bother with anything bigger than a 12 or 15...IME...

    PM me if you want advice, I can probably help...
  9. Kelly Lee

    Kelly Lee Yeah, I'm a guy! Supporting Member

    Feb 17, 2004
    Marana, AZ, USA
    I agree with you DEVILMAN.

    I ran two 18's way back but have learned I really didn't need them for the Thrash/Speed metal band I was playing in. I now use nothing but 15's and haven't looked back.

    Now if I was playing a 5 string in dropped A or lower I might consider an 18 a necessity again.
  10. csholtmeier


    Feb 8, 2004
    omaha, ne
    I would listen to the devilman on this one...

    Don't make the mistake of thinking just because you tune to C or B that you need to have an 18. They are too slow and everything turns to mud. I also tune to drop B, and I just run a 6x10.
  11. Tiny Tim

    Tiny Tim

    Jul 8, 2002
    Salem, Oregon
    I will think this all over, you all have been a great help. Thanks again!! Tim
  12. GO TO CARVIN.COM and get a OEM replacement. their most espensix speaker is 169.99 ans will go from 30-2.5k in eather 4 or 8 ohms and will handle 800 watts with a 4 inc voice coil. it should do.
  13. Only the cheap ones.

  14. I assume your cabinet is the Carvin RL118.

    If so, my guess at internal volume is no more than 6 cubic feet. The Eminence Magnum 18HO is a good match for this cabinet volume. You might have to fiddle with the tuning a bit, as the 18HO wants 30 Hz tuning in this volume.

    Running it without a crossover will not hurt it at all.

    The 18HO is good to 1,200 Hz before it rolls off. This is a premium grade driver, and neither a mud machine nor a sloppy prom date.

    Talk to Wayne Parham who frequents Bill Fitzmaurice's site. Wayne is a standup guy, and is an authorized Eminence dealer who can cut you a very competitive price, usually better than standard mail order.
  15. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Reach Wayne at www.Pispeakers.com
  16. Tiny Tim

    Tiny Tim

    Jul 8, 2002
    Salem, Oregon
    Thanks Again for the help! I have learned alot and thats what this sight is all about! :D Tim