Turning an empty 4x12 no-name guitar cab into a bass cab

Discussion in 'Amps and Cabs [BG]' started by 2400, Sep 19, 2010.

  1. 2400


    Sep 4, 2009
    Antwerp, Belgium
    So here's the deal: a while ago I had the chance to buy a stripped no-brand guitar cab, tolex in great shape, for €50 ($65). I've always loved the look of those big-but-not-too-big 4x12s, so this looked like an opportunity to turn this thing into a bass cab!
    Needless to say, I've got some questions. :)

    I'm away from home at the moment so I can't get any pictures up here, but what I can do is give you the specs!

    • 4 12" speaker cab, looks like a Marshall cab
    • Made out of really dense particleboard (which, I've heard, is not ideal but not a dealbreaker either)
    • No wiring
    • Basically open backed (makes no sense for a Marshall-style AFAIK), there's a 100mmx740mm (3.9"x29.3") opening at the rear, near the bottom.
    • Pre-cut for Orange/Markbass/Marshall style recessed handles
    • Dimensions: 750mmx740mmx285mm = approx. 158L (29.5"x29.3"x11.2" = 5.4cft), there's also some internal bracing, so perhaps a litre (approx. 60 cubic inches) should be substracted from the total volume

    I plan on using this cab with my Little Mark II at the moment, but may decide to hook it up to a currently nonexistent all-tube amp. I'd prefer to keep it on a budget however, so I'd like to spend no more than €300 (that's about $390; also sound > looks, I'll leave the grillcloth for now :p).

    I can pretty much guess straight away that I'm going to have to spend some time sealing this cab. Anything else, I'm open to suggestions! Speakers, switching, ports... any ideas?
  2. will33


    May 22, 2006
    Costs too much and you don't end up with anything near what you could get in a real bass cab for that money. Too small to make any kind of a 4x bass cab plus 4 speakers regardless of quality already make it more than it's worth regardless of how much if any other fixing needs to be done.

    I'd dump it and look for some used bass cab that's cheap and still works. It'll work better in the end.
  3. RickenBoogie


    Jul 22, 2007
    Dallas, TX
    +1, an excersize in spinning wheels. Guitar cabs are too small to be made into bass cabs.
  4. johnk_10

    johnk_10 vintage bass nut Supporting Member Commercial User

    Feb 16, 2008
    Thousand Oaks, CA
    John K Custom Basses
    i disagree. if you used only two 12's (vertically), sealed the back, added bracing, and ported it, and possibly added a 6.5 with an XO, i think it would make a great bass cab. i'm thinking of building up one of them like that myself with two 3012LF's and a 630SS (6.5" speaker). the top 12 and 6.5 would be up on the angled part so you could hear it on stage.

    IMO, the only downside on the cab that you have is that it's particle board, but i think that one made out of lite ply (like auraco) would be lightweight and sound (and look) great.
  5. Stick_Player

    Stick_Player Banned

    Nov 13, 2009
    Somewhere on the Alaska Panhandle (Juneau)
    Endorser: Plants vs. Zombies Pea Shooters
    I agree with JohnK,

    Using the old VOX Super Beatle cab dimensions, I constructed similar-sized one with a single 15" and two 10" speakers. I also installed the same horn used by GK.

    I used the WinISD program to match speaker and porting to the cabinet volume,.

    Also the 15" is in a separate chamber from the two 10" speakers.

    I'm very satisfied. And it looks awesome!
  6. will33


    May 22, 2006

    A sealed 212 it could make, no 4x though. Particle board = weak and heavy. If you like the looks, nothing wrong with that. With that goal in mind, if it were me, I'd likely strip it, build a "proper" bass cab and use the left over stuff to put a faux marshall front on it.
  7. rpsands


    Jul 6, 2007
    Phoenix, AZ
    As long as the cab is sealed and you add additional bracing, and you don't care about low end, sticking four Basslite S2012s in there would be fine.

    Even as low as 140 liters or so, probably accurate after the drivers, you're looking at a rolloff under 100hz, but -3db of 80hz which is more than acceptable for a bass cab (if you're not worried about super bottom).

    The cab with that alignment can take 300 watts no problem, 150 watts with +3db of corrective bass eq. The cab's sensitivity is like >100db above 100hz, which is monstrous for a rock cab. Distinct lack of boominess too I presume due to the high qts and low vas of the S2012.

    The downside is it's 8 ohms, but the upside is it'll get extremely loud even with a small tube amp.
  8. rpsands


    Jul 6, 2007
    Phoenix, AZ
    Honestly by my modeling, S2012s are fine in that box with a 45hz or so tuning as well. Little more boomy, but not too bad (+2db or so centered at 125hz). I wouldn't bother porting it though. It doesn't do much but add some boom, and extend your -3db point own to 70hz. Really not worth it unless you want a really fat bottom sound.

    Every time I look at models of the S2012, I am impressed. It's a really amazing little driver on paper.
  9. Sartori

    Sartori Supporting Member

    You could perhaps make a large 1x15 out of it. Or a 15 + 6 or something.

    What are the dimensions? Anything like the Marshall 1960B cabs? If you sealed it up, and used whatever kinds of speakers Steve Harris uses in his 1960B cabs, that might sound all right.
  10. will33


    May 22, 2006

    I'm of the same mind regarding the basslites. I'm still unsure why more folks don't recommend them and use them. I think it may be in part because there's a such thing as a kapplite now and it's easy to tell somebody they're wasting their time by not getting top shelf. Easy to say when it's someone other than yourself spending the money and doing the build. Also because the 10's and 12's have a 150 watt power rating. As little as that matters it still carries a lot of weight in the "more wattage is better" and "go to 2ohms to get more power, man" crowd which is most players.

    As far as the OP goes, basslites would be the best of the very few workable options he has for his marshall 412. The cost would be more inline with what a decent used or cheaper new cab would cost you. If you like the lowmid, bouncy or ballsy depending on how you play it, "vintage" sound without a lot of deeper lows it could be be workable. The particle board thing sent it over the edge for me.
  11. rpsands


    Jul 6, 2007
    Phoenix, AZ
    On the upside it will look really cool. :)

    A thing to remember is that speaker cabinets are insanely expensive in Europe. Even the cheapest decent stuff is going to be twice the cost of the Basslites most likely. I don't know what the used market is like over there but if it's anything like the new market, reloading this cab would be a good call.

    Europe is the kinda place where I'd build my own cab almost any day...four S2012's from thomann.de will set you back 340 Euro. Or you could drop 400+ on a cheap ass hartke cabinet. An Eden 4x10 is like 1200 euro.
  12. will33


    May 22, 2006
    Didn't know it was that bad there now. Haven't been there since '94. My carvin rig and my bass were both shipped from the US. I do remember strings being expensive though. That was just before.....and just after they took the borders down between us and Holland, Ostereich, Der Schweis, etc.:D