4x12 cab wired as separate 2x12 or blended

[kvxmg]

Hi guys.

ive got a 1960a cab and have replaced the speakers with 2 celestion g12h30 8ohms and ive got another 2 greenback 55hz 8 ohms.

my question is can i wire the cab in such a way that if i wanted i could use it as a traditional 4x12 with both the greenbacks and hertiage speakers working as a 4x12 but then also with option to plug in and only use the greenback pair or the heritage pair as a 2x12??

i realised i would probablly have to add jack plates or something but any help would be greatly appreicated.

Thanks,

Kosta.

 

[fitz]

Easy peasy.
Costs less than DIY parts.
Jack Plate - Plug and Play, Mono / Stereo | Antique Electronic Supply (tubesandmore.com)

 

[paul-e-mann]

Easy peasy.
Costs less than DIY parts.
Jack Plate - Plug and Play, Mono / Stereo | Antique Electronic Supply (tubesandmore.com)

Thats super cool, thats what I'd do if I ever got my hands on a 4x12!

 

[fitz]

Hi guys.

ive got a 1960a cab and have replaced the speakers with 2 celestion g12h30 8ohms and ive got another 2 greenback 55hz 8 ohms.

my question is can i wire the cab in such a way that if i wanted i could use it as a traditional 4x12 with both the greenbacks and hertiage speakers working as a 4x12 but then also with option to plug in and only use the greenback pair or the heritage pair as a 2x12??

i realised i would probablly have to add jack plates or something but any help would be greatly appreicated.

Thanks,

Kosta.

Can also be done with 2 cliff jacks, a regular jack, and a jack plate that has 3 holes.
Series wire each side to the cliff jacks (16ohm) and parallel wire the cliff jacks to the regular jack (back to 8 ohm).
Unless ya got the stuff laying around, parts would probably be more than $21.

 

[kvxmg]

Easy peasy.
Costs less than DIY parts.
Jack Plate - Plug and Play, Mono / Stereo | Antique Electronic Supply (tubesandmore.com)

looks cool! says on the site that it only works with 4x 16ohm speakers so seeing as i have 8 ohm i wont be able to run the 4x12 config?

 

[fitz]

looks cool! says on the site that it only works with 4x 16ohm speakers so seeing as i have 8 ohm i wont be able to run the 4x12 config?

Sorry, looks like it only does 2 x 8 ohm.
But my 2 cliff jacks and a regular jack is a possibility.
I can expand on how that works if you're interested.

2 x +

 

[C-Grin]

I need one of those for a 2x12 I have

 

[RLW59]

You could use the Plug & Play with four 8 ohm speakers. The impedances will be different than the labels on the jackplate, and one jack won't be usable unless you have a Fender Super Reverb, tweed Bassman, or other 2 ohm amp.

With four 8 ohm speakers you'd have:
All four 8 ohms (the jack labeled "16 ohms")
All four 2 ohms (the jack labeled "4 ohms")
Left pair 4 ohms
Right pair 4 ohms

Use a marker or label maker to change the labels on the jacks.

 

[kvxmg]

would there be a way to wire the left pair & right pair at 16 ohms then all for at 8ohms? so the pairs in series then both pairs in parallel?

 

[fitz]

would there be a way to wire the left pair & right pair at 16 ohms then all for at 8ohms? so the pairs in series then both pairs in parallel?

Yes, that's what the 2 cliff jacks and a regular jack would do.

 

[RLW59]

The list of altered impedances for the Plug & Play I gave is if you just use the standard wiring intended for four 16 ohm speakers.

If you use the wiring for four 4 ohm speakers, you'd get:

All four 8 ohms
All four 32 ohms
Left pair 16 ohms
Right pair 16 ohms

The Plug & Play is literally 2 switching jacks and a regular jack. Same as doing it yourself with parts. Neither approach is better or worse than the other; both give the same results.

If you already have appropriate jacks and a large jackplate, a soldering iron, and a drill (if you need to add a jack hole to your plate), it makes sense to do it yourself.

As fitz288 said, if you have to buy all the parts the P&P cost is pretty similar and there's no soldering or drilling needed.

 

[RLW59]

A different possibilty:

Does your amp have paired output jacks? If so, you could just add one jack to your cab. One jack connected to one pair of speakers, the other jack connected to the other pair.

When you want all 4 speakers, use two speaker cables from the amp to cab.

That has the advantage of not having an unusable jack and eliminates the possibility of accidentally plugging into a 2 or 32 ohm load.

Also eliminates the possibilty of a switching jack getting corroded or sticking open.

Minor disadvantage is you need to always carry two speaker cables if you want to run all 4 speakers together.

Bigger disadvantage is that there are a few amps that have single output jacks and you'd need a special parallel Y splitter speaker cable (or a parallel splitter box and 3 speaker cables).

 

[kvxmg]

Sorry, looks like it only does 2 x 8 ohm.
But my 2 cliff jacks and a regular jack is a possibility.
I can expand on how that works if you're interested.

2 x View attachment 99125 + View attachment 99127

keen! what do you have in mind?

 

[fitz]

keen! what do you have in mind?

These cliff jacks complete a circuit from side to side with no cord plugged in.
Plugging a cord in lifts the connection - the far side lugs go to the cord and the near side lugs are disconnected.

So run your series wired pairs to the far side lugs.
One of these jacks for each of the speaker pairs.
Parallel wire the near side lugs of both cliff jacks to a regular jack.
When you only use the regular jack, you'll have all 4 speakers parallel/series wired to 8 ohm.
If you plug into either or both of the cliff jacks, you'll have series wired pairs at 16 ohm.

 

[ampeq]

The Plug and Play plate fitz288 said is the way to go. I always keep an extra on hand, they work great.

 

[Gutch220]

Isn't this how 1960 cabinets are already wired.......? with the stereo/mono switch? I believe so.

 

[RLW59]

Isn't this how 1960 cabinets are already wired.......? with the stereo/mono switch? I believe so.

I completely blanked on that. Modern 1960 cabs do have switching jackplates.

If it has a single jack it's an older one that's bordering on "vintage collectable". Personally I wouldn't drill or cut for multiple jacks. I'd make a new plywood back panel and not molest the stock back panel. Especially if you still have the original speakers stashed away.

 

[Gutch220]

I don't know what cabinet you've already got, but you can buy the back assembly for the jacks.
$55
https://www.amazon.com/Jack-plate-G...02&sprefix=marshall+cabinet+ja,aps,896&sr=8-2

 

[1Louder]

Agreed, the 1960B I have is already set up like that. 2 V30's on one side and 2 G12T75's on the other. Put it in stereo mode and you can plug into either side for each set, or plug into both using duel outputs from your amp, or switch it to mono and get all 4.

I often wonder why more players don't do that. (unless you don't like blending speakers or you play loud and use low watt speakers).

Just for the sake of overkill I have an old Sunn 4x12 that I made a plate for. 4 speakers, 4 jacks.

 

[kvxmg]

update - i purchased the jack plug and play, i can get the left side working with just the g12h30s and the right side with just the greenbacks but when i plug in to the 16hm jack i get no sound.

i do get all 4 working when its plugged in the 4 ohm mono (but that nets me 2ohms) as im using 4 x 8 ohm speakers.

any ideas?