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Author Topic: Weirdest Request Ever - 3 speakers in a 4x12  (Read 8428 times)

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McLeanAB

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Okay...

It's gets even weirder...  Like most of us, I get caught in a financial slump and still love to play around and make due with all the fun gear I have... so...

What I have now is two 4x12 cabs... one is loaded with 4 25watt, 16ohm Celestion Greenbacks.  The other has two 8ohm 120watt Emience Man O Wars... I yanked out the two Celestion CREAMbacks and put them in my Theta Combo and Vector cab to replace the Eminence for fun and it sounds amazing...

So right now, both cabs are wired mono at 16ohms each.  Eventually, I'd love two more Eminence to fill out the other 4x12... but until I get the cash to do so, I'm wondering how feasible/safe it would be to put three speakers in each cab?  Two Greenbacks and one Man O War?  How the hell would I wire that???  Series?  Just one speaker after the other?  I know the ohm rating total would be something crazy (an odd number of some sort), but as long as it's somewhere between 4 and 8 ohms, the Stealth power amp should be fine... if this is even possible with the HUGE difference in watt ratings between speakers, I'll confirm with Buck at ISP about what the Stealth can handle...

Any thoughts, other than I'd be crazy to try?

The Man O Wars actually compliment the Greenbacks quite nicely, so I figured I'd mix 'em up and see what we get... help a brother out!!!
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-Adam
ISP Theta Preamp, ISP Theta PRO, ISP Theta Combo and Vector 2x12 with Celestion Alnico Creams, and Charvel Wildcards with EMGs!

MarshallJMP

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #1 on: Time Format »

Well it can be done, if you put the 2 greenback in parallel, this will give 8 ohms, then you can either put the eminence in series which will give you 16 ohms, or all 3 in parallel which will give you 4 ohms. So no crazy impedance's  :D

As for loudness, the eminence will be as loud as the 2 greenbacks together.
« Last Edit: Time Format by MarshallJMP »
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Systematic Chaos

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #2 on: Time Format »

Laboga has a 3x12 Cab (http://www.laboga.pl/en/312a-b#description). You basically wire 2 16ohms speakers in parallel (=8ohms) and then go to the 3rd speaker which is 8ohms in series = 16ohms total in mono.

« Last Edit: Time Format by Systematic Chaos »
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Kim

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #3 on: Time Format »

While the 4x12-into-3x12 cabs might be a good idea, I'd be sure to cover the unused 4th hole to maintain the original acoustic integrity of the box. 
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McLeanAB

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #4 on: Time Format »

You guys rock!

Got home from teaching, opened the cabs up, and followed the diagram... 8ohm MOW on top outside of both cabs, 16ohm Greenback on the top inside of both cabs, other Greenies on the bottom outside...  sounds AMAZING...

I did a little reading on what some call 'detuned' cabs... meaning, one 12" speaker in a 2x12 housing, or 3 in a 4x12... lots of folks like the open hole for some 'air.'  Have to say, I agree... sounds less 'compressed.'

LOVE IT... nice to know it's running at 16ohms so no danger of blowing anything up...  so... my next questions... the MOW are 120 watts, and the Greenies are 25 watts... what is the total per cab?

THANK YOU!  Everything sounds so even and clean now!!!
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-Adam
ISP Theta Preamp, ISP Theta PRO, ISP Theta Combo and Vector 2x12 with Celestion Alnico Creams, and Charvel Wildcards with EMGs!

Dante

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #5 on: Time Format »

Thanks for posting this! I have heard of other guys running 3 speakers in their 4x12s but always wondered about how to wire them up. I may try this with my EV and two Celestions. I can put one of the other Celestions in my 1x12 cab after taking out the EV.

Very cool.

McLeanAB

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #6 on: Time Format »

I know!  It's very cool...

Money is tight, so it's great not to have to buy two more speakers to fill it out... the 4x12's were a big experiment anyway, so it's great to move forward with that mindset...

And yeah, the 'openness' of the 4x12 with the one vacancy is almost 'loose' feeling/sounding compared to the compressed sound with all four speakers there... I much prefer it... I always felt like I was compensating with volume to combat what my ears were perceiving as compression - which I'm sure some folks love...

Dante, let me know how it goes! 

I was also a little shocked at how fun the MOW and Greenies work together... very interesting... the Greenies are much more smooth or, for lack of a better work, sophisticated, and the MOW's much more raw...
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-Adam
ISP Theta Preamp, ISP Theta PRO, ISP Theta Combo and Vector 2x12 with Celestion Alnico Creams, and Charvel Wildcards with EMGs!

Dante

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #7 on: Time Format »

This is gonna be a fun project, and I need to paint my grill, so I'll be taking it apart anyway....

I'm going to try this 3-speaker arrangement with 1 EV Force (150w/8ohm full range speaker) and two Celestion G12F 60 Rockdriver Jrs (I think) that are in the cab. I can't find a lot of info on the Celestions online. I think they were proprietary to H&K.

I have a question; what would be the best arrangement for this? Should I put the two 60w speakers in the bottom and put the EV up top with the open hole? I suggest this because the EV sounds pretty bright by itself.

One thing that interests me, is to mic the hole versus a speaker, and to compare the speakers themselves. I may pick one speaker to mic, or mix two, or mic the hole.  :dunno:  Just gonna go on ears & see what sounds best

Systematic Chaos

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Re: Weirdest Request Ever - 3 speakers in a 4x12
« Reply #8 on: Time Format »

Get 2 pieces of decent multilaminate/plywood from your local wood supply store/Home Depot and make a new/2 new baffles, single 12"" hole bottom center, 2 12" holes top. EV in the bottom, Celestions (the Celestion/H&K OEM Rockdriver 60s are variants of the V30) top.
Maybe some cutouts on the outer bottom half to make it ported so it can breathe some...

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Dante

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