Vintage 2x12 Halfback

[Zlofengir]

My Boogie Brethren, I have come to pick your minds, and seek out your wisdom...

I have the opportunity to get my grubby paws on an '80's Halfback, but haven't been able to find any up for sale to get a ballpark price. Can you guys give me any idea what the going rate is on these now?

I know that I'm going to run into an impedance mismatch with my Mk II combo, until I can find a 4 ohm 15"; which would be easier than trying to replace the 12's... Pretty sure that running the 8 ohm speaker at 4, along with the 4 ohm Halfback wouldn't be a very smart idea.

But, I think when it's all said and done, it's going to be the most insane "stack" in town!

Thanks for your help!

 

[gts]

It'll depend on what speakers in the 2x12 halfback cab.
Generally speaking I'd say the cost would $350 and up. Again it all depends on what speakers are in the cab.

 

[kdorsey]

I agree with gts. In clean condition with the stock config of C90/EV, I see them go for $500 range...when they come up. The big problem is finding them, then shipping them! If you have one locally, grab it.

 

[Zlofengir]

I agree with gts. In clean condition with the stock config of C90/EV, I see them go for $500 range...when they come up. The big problem is finding them, then shipping them! If you have one locally, grab it.

Yeah, it's local; actually from a friend of a friend... He's asking $400.00, but I haven't seen it, and not sure of the speaker config, or age. I know they don't pop up often, that's why I wanna grab it; they're great sounding cabs!

 

[morgan138]

I think the impedance would be just right actually - with an 8ohm speaker in the combo and two 8 ohm speakers in the cab, each speaker would be drawing 1/3 of the amp's power output. Total impedance would be 2.66 ohms, which isn't ideal but I bet wouldn't be the end of the world if you ran the amp at 4.

If you put in a 4 ohm combo speaker, not only will that one speaker be drawing as much as the entire extension cab (so, 2x as much as each of the speakers in the cab), but your total impedance will drop to 2 ohms which'll be more likely to cause issues than the aforementioned 2.66.

 

[Zlofengir]

I think the impedance would be just right actually - with an 8ohm speaker in the combo and two 8 ohm speakers in the cab, each speaker would be drawing 1/3 of the amp's power output. Total impedance would be 2.66 ohms, which isn't ideal but I bet wouldn't be the end of the world if you ran the amp at 4.

If you put in a 4 ohm combo speaker, not only will that one speaker be drawing as much as the entire extension cab (so, 2x as much as each of the speakers in the cab), but your total impedance will drop to 2 ohms which'll be more likely to cause issues than the aforementioned 2.66.

If it's designed for two 8 ohm loads, that's what I'll use... There are some risks that aren't worth taking; blowing up my '78 Mk II by mismatching the impedance ain't one of them.

 

[dodger916]

I think the impedance would be just right actually - with an 8ohm speaker in the combo and two 8 ohm speakers in the cab, each speaker would be drawing 1/3 of the amp's power output. Total impedance would be 2.66 ohms, which isn't ideal but I bet wouldn't be the end of the world if you ran the amp at 4.

It depends on how the cab is wired, series or parallel. Assuming parallel (which is common), the 2.66 total load run from the 4 ohm taps should be a safe mismatch. I would check impedances first because every speaker I've tested shows lower impedance than the rating, meaning your total load could be less than 2 ohms, which is on the border of "safe mismatch".

Another option is to wire the 2x12 in series, resulting in 16 ohms, which when run in parallel with the other 8 ohm cab would result in 5.33 ohms total load. Run separate cables (one for the combo speaker and the other for the 2x12) off the 4 ohm taps and you're definitely good. Either way, Mesa uses very durable transformers, so aside from drastic mismatches (more than double or less than half), you should be fine.

 

[Zlofengir]

Ok, boys... I got it!! From the logo, I'm guessing '90's... Celestion MC-90 on top, Eminence VS-12 on the bottom.

Gonna put an EV-12L in the bottom, and the VS-12 on top... Should make for 250 watts of groovacious tones.

 

[Zlofengir]

Correction... Now that I've looked at the old 80's catalog, I see that this cabinet is from that era. It has the Cream on Black painted aluminum Mesa/Boogie logo.

Now that I've had my way with it and put in the EV12-L on the bottom, And the Eminence VS-12 on top, my Mk II sounds incredible through it! (Naturally!!) Both my Strat and Les Paul are absolutely smoking through it!

Can you say happy Tone Junkie???

 

[Zlofengir]

Getting a Recto 212 stereo jack plate from Mesa... This way, I can run my 15" with either or speaker in the Halfback... Or, just the Halfback.

 

[kdorsey]

Congrats on the success! FYI, the '90s era jack plate can also be used in a stereo config. You'll have to cut a bigger opening for the plate, but it works.

 

[Zlofengir]

Congrats on the success! FYI, the '90s era jack plate can also be used in a stereo config. You'll have to cut a bigger opening for the plate, but it works.

They're whipping together one of the current plates for me; it should be here later this week. I thought about an aftermarket jack plate for $6 less, but, having a Mesa branded one increases the resale value; not that I have any intention of parting company with this baby anytime soon. :mrgreen:

 

[kdorsey]

...You'll have to cut a bigger opening for the plate, but it works.

...having a Mesa branded one increases the resale value

If you have to take power tools to the cab you can't be worried about resale value. :wink: Make sure there's still a piece of rock wool insulation in the bottom section. That takes the boxy tone out of the cab.

 

[Zlofengir]

...You'll have to cut a bigger opening for the plate, but it works.

...having a Mesa branded one increases the resale value

If you have to take power tools to the cab you can't be worried about resale value. :wink: Make sure there's still a piece of rock wool insulation in the bottom section. That takes the boxy tone out of the cab.

There's plenty of insulation in the bottom, I even added an extra piece of acoustic foam to cover the rear panel.
I have no problems making certain modifications to vintage equiptment, if it is for good tone's sake. Like I said, I have NO plans on parting company with this cab any time soon; I have my dream rig now, and my tone is near perfect.

 

[Zlofengir]

If you have to take power tools to the cab you can't be worried about resale value. :wink: Make sure there's still a piece of rock wool insulation in the bottom section. That takes the boxy tone out of the cab.[/quote]

There's plenty of insulation in the bottom, I even added an extra piece of acoustic foam to cover the rear panel.
I have no problems making certain modifications to vintage equiptment, if it is for good tone's sake. Like I said, I have NO plans on parting company with this cab any time soon; I have my dream rig now, and my tone is near perfect.[/quote]

End results... http://zlofengir.tumblr.com/post/120456717316

 

[gts]

Nice job!

I've got black screws for the plate.
If you want four let me know.

 

[Zlofengir]

Thanks, G... I used what was on hand; not like anyone is going to see it any time soon. I can always get black screws at the hardware store. Or use a Sharpie. HA! :twisted: :twisted: