Homemade Speaker Cabinet

T

Trippalot

New member
Hey. What's up. Tripp here.

I'm making a 4 x 12 cabinet. The carpentry's good, but when I tried it the first time, the speakers kept "locking up" on me; they would get stiff. So I sold the head I was using, took all the speakers out, and I'm giving it another whirl with a head that I haven't bought yet, but it's coming.

I'm using two Fender speakers that came out of a Fender Reverb amp and two Celestion 75 watt speakers. All four speakers are 12". The problem is, I'm not exactly sure how to wire them all together. Might sound stupid, but the first time I did it I wired each speaker to a separate terminal. Do I need to bridge them in some way?

I'll position the Fender speakers on the top and the Celestions on the bottom. Is there a specific gauge of wire that I need to use? Do I wire all four of them to one 1/4 inch jack in the back? Does the cab need to be sealed, or do I need a few holes or even a half open back?

I'm pretty blind as far as the wiring goes, and I can't seem to find anything on the subject around the internet; only stuff about building tube amps and complex wiring diagrams.

Help!!!!!! Any assistance will be GREATLY appreciated.

Thanks.

Tripp
 
I will assume the speakers are 8 ohms. If you wire two in paralell they will become a 4 ohm load. wire the other two in paralell then wire the two 4 ohm loads you have made in series with one another and you will come out with 8 ohms. If you wire all 4 in series you will have a 32 ohm load which is not good for your amp. If you take the two 4 ohm loads you have wired up then wire them in paralell you will come out with a two ohm load.
If you wire any resistors in series (speaker ohms) the resistance(ohms) is the addition of all the resistors added together. If you wire any two resistors in paralell they are half the total resistance.
 
So wire the top two speakers like so:

positive to positive
negative to negative

and wire the bottom pair the same way.

That means now I essentially have two positives and two negatives remaining, right? (Basically the top two speakers are now being treated as one speaker and ditto for the bottom pair).

I have one quarter inch jack which will mount in the back(should it be open or closed circuit, by the way?). What do I do with the remaining two positives and two negatives?

Thanks.
 
I never wire them, I just know how it works. I am sure if you do a search on the web you will probably find a diagram for wiring them up. someone else will problably chime in here soon and give you the info or the link you need so just hang in there. You could go to your local music store where they do repair work and ask the dude to draw you a little diagram. If he isnt a dick he will probably gladly do so, if he is a dick, dont ever go back.
I could probably figure it out but dont want to steer you wrong. If they get wired up to the wrong resistance rating for your amp it could do damage. By the way, next time you post try and post what ohm each speaker is and what
rating the load is for your amp??? Some amps have a swith for different loads so you can use a 16 8 4 or 2 ohm load.
I just posted an SOS in the dragon cave for ya, someone should be here soon to help ya out.
 
Tripp,

You say you are getting another head............find out what it's impedance ratings/capabilities are for speaker loads, then contact(yeah, I mean email) the manufacturer, giving them the speaker details and ask if they can supply you with a suitable wiring diagram.

:cool:
 
Make sure the speakers are meant to carry the same load (the fenders and celestions). Ohm and wattage.

I could be wrong but it sounds like a good way to mess up your amp or blow the weaker speakers if they are mismatched.
 
OK, I've got two Fender speakers with 8 ohms apiece and I'm not sure of the wattage power; they came out of a Fender 100 watt Reverb amp. The other two are 75 watt Celestions with 8 ohms. Hope that clarifies a little.

Thanks.
 
OK here goes. If you have the Fender's wired pos to pos and neg to neg and the celestions the same way; then you take the pos from the fenders and hook that to the neg from the celestions. then the pos from the celestions goes to one connector of the jack and the neg from the fenders goes to the other side of the jack It's called series-parrallel and will give you a total of 8-ohms.
Did you follow that? The Fenders are wired in parrallel giving 4-ohms. The celestions are also wired in parrallel giving them 4-ohms. Then you are taking the combined wires of the speaker pairs and treating them like single speakers and wiring THESE in series which is 1 speakers' (or pair of speakers) pos to the jack; the other speakers' (or pair of speakers) neg to the jack and the remaining pos to the remaining neg.
be aware that if one type of speaker is substantially louder than the other, they will be doing most of the work. Hope this helps. :)
 
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Lt. Bob:

Excellent! So do I wire all four speakers to one quarter inch jack (opened or closed circuit)?

Also, do you recommend sealing up the enclosure or creating a few holes like you would a subwoofer enclosure?

Thanks a lot for the help.

Also thanks to dragonworks for putting the word out and texroadkill and ausrock for your fast responses.
 
One jack is fine. Just so long as you're clear on how to wire them all together. I'm not sure what you mean by open or closed circuit. Explain further if that's an issue.
As for the holes, it depends on what you want but most of the 4-12 cabs I see have no holes. Small holes won't make much difference and large ones will mean less bass like in a open back cab.
 
Trippalot,
I am interested to see what sound you get as I am keen to make up a cab with 2 Celestions, I have a Cab that I made up with the two speakers from my Fender Twin, these are made for Fender by Eminence and I made an open backed cabinet that is about the same size as the Twin without the amp which is now a separate head, it sounds magical, all the bass I need, inspite of the low public opinion of Eminence, so if you get a good sound from your new set up please post it for all to see.
What model Celestions are they?
Good luck.
Clive
 
Jahmbo: Thanks for the web address for the drawing. It gave me a chance to visualize what I'm doing.

Clive Hugh: I will definitely post a response on this board after I set everything up to let everybody know what kind of sound I get out of this cab.

Thanks.
 
amp head

OK; got the cab completed!! Now I'm looking for a head. Has anyone every used a PA head to power a cabinet? Is there any reason I need to use a head specifically known as a guitar head? I figured since I have a pretty vast array of pedals and sound modeling stuff, I may not need an amp known for clean and overdrive channels. Just a thought. What do you think?
 
Well, if you have some amp modelers, then a PA head might work ok. Especially if it has a power amp input that would bypass the preamp (the tone controls and stuff) Even if it doesn't you could still use it. I'd set it for a clean flat sound and then rely on my modelers to get the tone and distortion the way I wanted it. This isn't an ideal solution but should work well enough.
 
If u are gonna get a PA head to power it why not just buy a rack mount power amp? That is as long as u have got some kind of pre-amp/modler!
A rack mount will give u the power u need to power your cab and wont mess around with the sounds out of ur pre-amp!
But I PA head would be fine if u plug ur Pre-amp into to the FX return and u get the same thing as a power amp!
(This might be a solution, but a head always looks cooler! ;))
C ya
craze
 
I'm guessing that Tripalot already has a PA head and he doesn't want to spend $bucks if he can avoid it; but if that's not the case then c_r_a_z_y is right, a power amp would be better. HOWEVER, if your PA has a power amp input, that would be the same thing and although I hadn't thought of it, your effects return would be very similar in practice. Good luck, let us know how it works. :)
 
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