Wiring a 4 x 12 cabinet

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Basically it's the lowest wattage speaker that is the constraint. So if you had 3x 200w EVs and one 25W greenback in a 4x12...that whole cabinet would be rated as if all 4 speakers were greenbacks because the power is generally divided equally among the speakers. Now, how Friedman gets 110W is a good question. Maybe they consider the GB a 27.5W speaker or something. Not everyone rates the V30 at 60W...some rate it at 70W so maybe it's similar to that.

Dave Rocks":1mpb6z9c said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

CrazyNutz":3dyaeum0 said:

Dave Rocks":3dyaeum0 said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

Click to expand...

Thanks - so like the attached?

Dave Rocks":1fe3e6vt said:

CrazyNutz":1fe3e6vt said:

Dave Rocks":1fe3e6vt said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

Click to expand...

Thanks - so like the attached?

Click to expand...

That will work. If you want to do it exactly the same as dave's cabs then rotate the image by 90 deg either way. But if you just leave the wiring the same in the cabs as it stands you will be fine too, Im assuming you're 1960 cabs have the stereo backplate right? if so its much less a pain to just leave the wiring as it is.

CrazyNutz":2d6dc2uh said:

Dave Rocks":2d6dc2uh said:

CrazyNutz":2d6dc2uh said:

Dave Rocks":2d6dc2uh said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

Click to expand...

Thanks - so like the attached?

Click to expand...

That will work. If you want to do it exactly the same as dave's cabs then rotate the image by 90 deg either way. But if you just leave the wiring the same in the cabs as it stands you will be fine too, Im assuming you're 1960 cabs have the stereo backplate right? if so its much less a pain to just leave the wiring as it is.

Click to expand...

Yes, I will do rotated - I just grabbed that image from the net for the series / parallel relationship. Yes, my cab has the stereo jack plate. So to be clear - the OEM cab is already wired this way and all I need to do is swap the speakers?

Thanks for the help.

Dave Rocks":lnjisiwf said:

CrazyNutz":lnjisiwf said:

Dave Rocks":lnjisiwf said:

CrazyNutz":lnjisiwf said:

Dave Rocks":lnjisiwf said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

Click to expand...

Thanks - so like the attached?

Click to expand...

That will work. If you want to do it exactly the same as dave's cabs then rotate the image by 90 deg either way. But if you just leave the wiring the same in the cabs as it stands you will be fine too, Im assuming you're 1960 cabs have the stereo backplate right? if so its much less a pain to just leave the wiring as it is.

Click to expand...

Yes, I will do rotated - I just grabbed that image from the net for the series / parallel relationship. Yes, my cab has the stereo jack plate. So to be clear - the OEM cab is already wired this way and all I need to do is swap the speakers?

Thanks for the help.

Click to expand...

No the OEM Cab is not wired that way. The OEM cab has right side in parallel, and the left side in prallel, and then series at the jack if in mono mode.

Just put the speakers in and wire the cab the same.. you will be happy.

CrazyNutz":2f28t3yw said:

Dave Rocks":2f28t3yw said:

CrazyNutz":2f28t3yw said:

Dave Rocks":2f28t3yw said:

CrazyNutz":2f28t3yw said:

Dave Rocks":2f28t3yw said:

So, I've got a 1960A Marshall cabinet that I'm going to take the original speakers out and replace them as follows:

Top: (2) Celestion G12 M Greenbacks, 25W, 16 ohms each

Bottom: (2) Vintage 30, 60W, 16 ohms each

This is the same combo Friedman does in his cabs (not sure if the same ohms though).

His cabs are 110 W, 16 ohm.

So, what is the best way to wire these? Seems the upper should be in parallel with each other, the lower in parallel with each other and the top and bottom in series - that would yield 16 ohm cab, 170 W - correct?

How does Friedman get 110W?

Thanks in advance.

Click to expand...

Dave's cabs use 16ohm too. The upper GB's are in series, and the lower v30's are in series and then both pairs are paralleled.

Iv'e done this with two 1960av cabs so far. Just wire it the same way it was originally wired (i.e. each GB will be paralleled with a V30)

And yes your cab will be 100w after adding the GB's. not sure where the 110w comes from, I've seen older Friedman cabs say 170w but this is wrong.

Click to expand...

Thanks - so like the attached?

Click to expand...

That will work. If you want to do it exactly the same as dave's cabs then rotate the image by 90 deg either way. But if you just leave the wiring the same in the cabs as it stands you will be fine too, Im assuming you're 1960 cabs have the stereo backplate right? if so its much less a pain to just leave the wiring as it is.

Click to expand...

Yes, I will do rotated - I just grabbed that image from the net for the series / parallel relationship. Yes, my cab has the stereo jack plate. So to be clear - the OEM cab is already wired this way and all I need to do is swap the speakers?

Thanks for the help.

Click to expand...

No the OEM Cab is not wired that way. The OEM cab has right side in parallel, and the left side in prallel, and then series at the jack if in mono mode

Click to expand...

Thanks. If I was going to run in Stereo, I'd use to cabs anyway.

-I'd rip that tone sucking, mono/stereo switch & PCB assembly out and just utilize the input jack hole/s,

-I'd also wire it like Dave does, so that the 2 GREENBACKS in series, the 2 V-30's in series-(you could use one input for the GB's & one for the V-30's, this would give you extra flexibility with other cabs/speaker combinations)-I actually utilize the 2 pairs in parallel, giving you 2 8 ohm outputs, and!! To even complicate things even more-(hey, I'm on a roll!)-2-16ohm V-30's-(mesa or Marshall's)-& 1-8ohm-55hz-greenback, one empty hole-(detuned cab)-with this set up, the single 8ohm, 55hz, 30w, greenback, over powers the 2 V-30's, but!! In a very complimentary way!! Very, aggressive, very firm bass, some would be concerned about the lone GB & the lower cab rating, the results are very impressive.

Done and sounds killer!

Just a nickels worth of free advice... when running the wires do NOT trust them super tight. Just simply twist them by hand. Twisting them tightly increases capacitance. This was shown to me by a real amp builder/ designer many years ago.

psychodave":2bsdtlo5 said:

Just a nickels worth of free advice... when running the wires do NOT trust them super tight. Just simply twist them by hand. Twisting them tightly increases capacitance. This was shown to me by a real amp builder/ designer many years ago.

Click to expand...

Not twisted as all - the wires all have connectors on the ends.