convert 4x10 to 2x10????

Birdland11 · #1 06-22-2011, 07:54 PM

Hi, not sure if i can do this or not but.... I have an acoustic b410 cab(with tweeter) with one blown speaker,its an 8ohm cab, and each speaker is 8ohm...Is there anyway possible i can just run two speakers? will the ohms be different? Obviously im new to this and am not sure what to do. I wanna use it as an external cab with my markbass 2x10 combo, which is 300w by itself and 500 with an 8ohm external cab....What can i do??? PLease help me.... THANK YOU

Figure It Out · #2 06-22-2011, 10:07 PM

Where did you buy it from? If you bought it from Guitar Center they actualy have a really good return policy. If not you can always get the speaker reconed. If you don't have money for that then sure, disconect the blown speaker and another to make a functioning half 410. If you actualy want to make a 210 and hack the thing it half... I guess you could do that

Birdland11 · #3 06-22-2011, 10:12 PM

Thank you so much....the ohms stay the same???I just dont wanna mess up my markbass. Thanks again

tjh · #4 06-22-2011, 10:24 PM

you will end up with either a 4 ohm cab if you leave the wiring as is (parallel), or 16 ohms if you wire in series ... there is no way two 8 ohm speakers can end up with a final IMPEDANCE of 8 ohms ... FWIW, I would either get the speaker repaired/replaced, or replace the entire cab with something suitable for your purpose ... if you want an 8 ohm 210, get one designed as such ... JMHO

Birdland11 · #5 06-22-2011, 10:24 PM

WAit! Doesnt two 8ohm speakers equal 4ohms???

Birdland11 · #6 06-22-2011, 10:27 PM

There is no way this can work is there?

Figure It Out · #7 06-22-2011, 10:32 PM

Well, whats the model of your combo, I don't know if it only goes to 4ohms. If you wired two of the speakers in series you would have a 16 ohm cab, if you wired two of the speakers in parralel you would have a 4ohm cab.

I honestly think your best bet would be to spend the $50 and get the speaker reconed or take it to a tech. If your unsure about it I think that would be your safest bet.

Don't quote me on the ohms stuff, Im not realy knowlageable about that.

Edit: Looks like you got to it before me.

Birdland11 · #8 06-22-2011, 10:39 PM

Its funny cause what happened was this...when it was all wired up i tested it with the markbass,and it seemed like only the top left and bottem left speakers work. The top left was farty so i pushed in and heard static, but it passed the 9volt test. So im guessing that one is blown right? I dont know why the other two werent working.... oh well, thanks anyway

Figure It Out · #9 06-22-2011, 10:46 PM

Well, it could have a few causes. I've heard of having loose connections. Maybe check those. You heard static? Maybe see if the cone is hitting something.

Selta · #10 06-23-2011, 12:17 AM

"Static" was probably the voicecoil rubbing. If that's the case, it's pretty much toast.
You could, technically, disconnect two speakers and have effectively a 4 ohm, 2x10 cab, after re-wiring the working ones in parallel. Since I don't know what combo/head we're working with here, I can't say for certain, but I can't imagine it not working OK with a 4 ohm load.

tjh · #11 06-23-2011, 01:27 AM

... but, the OP is looking to use this as an extension cab, to his MB combo, which is probably only 4 ohm capable ... he needs a cab with a minimum impedance of 8 ohms ... besides, I have no first hand knowledge of an Acoustic 410 cab, but the box internal size, porting, etc, is more than likely designed for the 4 10s, not for 2 10's ...

tjh · #12 06-23-2011, 01:31 AM

Quote:

Originally Posted by Birdland11

WAit! Doesnt two 8ohm speakers equal 4ohms???

Wired in parallel, yes they do ... but how does this help you to use with your MB combo? ... I think that would only be a 4 ohm capable head, not 2 ohm, correct? ... if so, your impedance load with the two speaker 410 (4 ohms) and your combo speakers (8 ohms) would be 2.65 ohms, or below your minimum impedance ... ??

Selta · #13 06-23-2011, 01:34 AM

Quote:

Originally Posted by tjh

... but, the OP is looking to use this as an extension cab, to his MB combo, which is probably only 4 ohm capable ... he needs a cab with a minimum impedance of 8 ohms ... besides, I have no first hand knowledge of an Acoustic 410 cab, but the box internal size, porting, etc, is more than likely designed for the 4 10s, not for 2 10's ...

Somehow I totally skipped over him wanting to use it with the combo. In that case it likely won't work, unless it's safe to 2 ohm. But with the likely impedance mismatch, it wouldn't be ideal too (the ext cab would get 2x the power of the internal drivers).
Yup, it wouldn't be ideal anyway to just unplug the dead drivers. It'll work, technically, but may sound like crap.

billfitzmaurice · #14 06-23-2011, 07:11 AM

Quote:

Originally Posted by Birdland11

Hi, not sure if i can do this or not but.... I have an acoustic b410 cab(with tweeter) with one blown speaker,its an 8ohm cab, and each speaker is 8ohm...Is there anyway possible i can just run two speakers?

Only if you cut it in half and make it into two cabs. Otherwise the cabinet tuning will be AFU. Replace the blown driver.

BassmanPaul · #15 06-23-2011, 10:26 AM

IIRC no MarkBass amp can handle less than a 4Ω load except possibly the full tube amp. I bet the combo already has a 4Ω load from its internal speakers. The OP needs to get a re-cone, if the proper kit exists, or a replacement driver from GC (Acoustic).