What makes a good extension cab?

100LL

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empty extension cabinets (speakerless), is there a noticeable difference?

Looking at extension cabs to fill with my own speaker choices, and there’s a ton of options at a wide range of price-points. Seems to me they’re just a box and a badge. So long as they don’t rattle is there any difference? I get the open vs. closed back thing, and am looking for a cab that has a removable panel so I can run it either way.

Please educate me on the topic.
 

northernguitarguy

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I'm curious, too. I'd offer that if your back matters to you, pine cabs are easier to slug around than MDF.
 

cybermgk

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FAR from an expert, but yes various things matter on cabinets. It really is more than a box with a speaker.

What it is made of, makes a difference. Pine, used in older Fender Combos, primarily for it's lighter weight, also flexes more than other choices. THis makes it less than ideal for anything but Open back, as that flexing accentuates certain frequencies more. THis is why most closed back CABs (and some combos) are made from plywood. But whether said plywood is voidless (i.e. no trapped air in the plys) makes a difference. Air trapped, rattles when used in a cabinet.

THis is one reason Baltic Birch Plywood is a preferred wood for Cabinets. Each ply is uniform thickness, no air, very rigid. It is also heavy.

Mass of the cabinet is also needed to get all those Bass frequencies. THis is why a lot of Bass CABs are made from particle or chip board. Downside, is, because of how it is made, it deteriorates over time.

YOu also want good corner joins. Bad joins allow flexing (see above).

THe font of the CAB, where the speaker mounts, the Baffle, needs to be THE most rigid part of the CAB, and it's joins to the CAB even more crucial than the sides. THE most chance for flexing is here. Even in a solid wood CAB, the baffle will mostly be Blatic Birch Ply or even MDF, because of this.

Air volume of the Cab, affects air flow, and thus speaker movement, which of course, affects the frequencies reproduced. Placement of the speaker in that volume makes a difference.

A Bass reflex port or not on a closed back CAB effects efficiency and tone. Generaly speaking a completely closed back CAB needs to be a lot bigger than a closed back ported (i,e, with a Bass reflex port) to be as loud and have as much bass response. A all closed CAB, all of that bass response comes from the speaker only. With the Reflex port, some comes from there as well.

All of this is why sometime some speakers just don't work as well, or sound as well to someone's ears in different CABs.

THis is the extent of my layman's knowledge, and I believe it all accurate. But, as I said, it's layman, and I am NOT an expert.
 

drew365

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No expert here either, but when I was shopping for a 1x12 cab, I looked for finger jointed pine in an oversize proportion. Larger cabs have always sounded better to me, less boxy. The 1x12 that I bought is about 21" x 20" x 11.5" if I remember correctly. It's at our rehearsal space, so I can't measure it now. It's open back and sounds great to me with a Celestion G12H 75 Creamback in it.
 

100LL

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My opinion...roll your own.

I made these two open-backs with what I found at Home Depot. 12" wide pine on the sides. 1/2" AC plywood on the front and back. Sheetrock screws and glue at the corners. It ain't rocket science. It's a box. The most expensive part was the expanded metal to protect the speakers. I have less than $100 in each cab, and that includes the very-well-broken-in Eminence Legends I picked up from a local metal head. Best part is I can throw these in the back of the truck and not give a damn what happens to them.

Looks perfect for a prison gig :)
 

hbucker

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I too, am no expert. But I own a 212 extension cab and have a little bit of general experience. My cab is the Seismic Luke, plywood cab that sells on the interweb for $200. It sounds just fine with my 5150 III amp and loaded with Warehouse speakers. Is it the "best?" ...I really, really doubt it. But it works just fine.

Make sure you're familiar with differences between the characteristics of an open back vs. closed back cab.

(Skip this step if you're not on a tight budget) Next, it's important to decide what your use of the cab will be. If it's never going to leave your studio, MDF is probably just fine and will save you $$. No, it won't last as long and isn't as durable, but it is durable enough to just set there and will be good for a couple of decades before you'd notice any real degradation in the wood. Yes, it's noticeably heavier, but if you're not moving it, who cares?

If you're going to play it out, there is the range of how much you're moving it: weekend warrior to touring pro. This would turn you in the direction of birch plywood, which is much lighter and more durable. Construction styles outlined by others would indicate how much durability you'll need for it to survive the loading and unloading it will be subjected to.

Sonic differences are there between different designs and sizes. At the risk of having people throw rocks at me, unless you have the ability to line up all of the cabs you're looking at and listen to the differences, you'll probably just need to find the cab that fits your needs, specs and budget. Be happy with it and use it until you don't want to anymore.

After that, the "fun" (depending on your perspective) is finding the speakers that sound best in your cab. Speakers and using the EQ on your amp can accentuate or compensate significantly for any inerrant traits of your cab. This hunt for the right speakers would be there for any empty cab you buy, regardless of the price. Just because it's an expensive, awesome cab doesn't mean it will sound good loaded with any speaker you put in it.

FWIW: Harley Benton is selling a 212 plywood cab loaded with V30s for $150 which is almost unanimously heralded as worth every penny and not a bad cab at all. There are MANY Youtube videos comparing the Harley Benton cab to the $800 Mesa cab, also loaded with V30s. There is a subtle audible difference in the cabs, but it's more of a "difference" and less of an issue of "good" or "bad."

These videos would be good for you to check out just to see how some of the points we're making on this thread can be extremely subtle. Especially if we're talking about a $600 difference in price tag. To my previous point: weekend warrior: Harley Benton. Touring Pro: Mesa. Everyone's happy. Nobody sounds bad.

At some point, you just need to make your choice and it will probably work just fine for you, as long as it doesn't rattle and you're willing to play around with what drivers you put into it.

Good luck!
 

grumphh

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So, how did Marshall arrive at his "industry standard" cabs?

Sheer bloody luck.

He made a box just big enough to hold 2 12's side by side and then for good measure (and because it looked menacing) added two more below those. And he made it sturdy enough to withstand roadies.

And lo and behold, it made electric guitars sound great (and loud). :yesway:

...cabs are just boxes to hold your speakers, and only corksniffers talk about "different construction resulting in different tone".

You put your ear (with hearing protection) up against a cab that is subjected to something like 50 - 100w rms from a nice turned up amp, and tell me you can hear whether it is baltic ply or pine :D
...oh, and be sure to hear the air pockets rattling in sub par plywood - those will totally be audible over the ~120 dbspl racket you make.

...most people would just be happy to get away from the cab without tinnitus...
 

Deftone

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My opinion...roll your own.

I made these two open-backs with what I found at Home Depot. 12" wide pine on the sides. 1/2" AC plywood on the front and back. Sheetrock screws and glue at the corners. It ain't rocket science. It's a box. The most expensive part was the expanded metal to protect the speakers. I have less than $100 in each cab, and that includes the very-well-broken-in Eminence Legends I picked up from a local metal head. Best part is I can throw these in the back of the truck and not give a damn what happens to them.

Nice! I got one similar....

IMG_2640a.JPG
 

redking

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I would say your choice of cabinet is extremely important, but unless you know from experience how your particular amp played at the volume you are playing it, through the speaker you are choosing all reacts together then there is no way to make an educated choice. In that case, stick to what our wise elders have discovered in days of yore. Marshall? - try a more rigid closed back, Fender & Vox, try a lighter weight open back.
 

100LL

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I already own this one Fender 112 extension cab in tweed but with my own speaker in stead of the stock one that it normally comes with. It’s not an expensive ext. cab. It is closed back.
I’m looking to get another cab eventually, but either 212 or 210, loaded with a V30 and something else. Maybe two Vintage 30’s, maybe a V30 and creamback or who knows.

Hence the question and discussion here. I was looking at the Mojotone cabinet makers, which look pretty good, but kind of expensive. I like to support domestic or at least continental/western manufacturing. You can’t always tell the materials used (some tell you, others don’t). It does seem to be that a good brand name gets a premium as you would expect. But there are, for instance, Marshall cabs at all the price points.

One thing that does interest me, and does lend itself to some sort of home build or at least mod, is to have twin speakers selectable between L, R and Parallel. Of course that’s just a harness mod. I’ve seen it stock on at least one cab. Also, a removable panel to go closed back to open back is also a somewhat rare stock feature.

 

LP1865

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Anyone have any experience with solid hardwoods for cabs, such as mahogany, rosewood, oak, walnut etc. ?
 

efstop

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I have three cabs but have never A/B/C'd them:

Vox Night Train 112, open back MDF with a Greenback. Slightly smaller than a Class 5
Hughes & Kettner TM 112, closed plywood with a V30. Deeper than the NT112
Marshall 1974CX 112, open back plywood with aged Greenback 20W. It's big, the same size as the 1974X combo.

They all make my guitars loud.
 

tzd

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I was looking at the Mojotone cabinet makers, which look pretty good, but kind of expensive. I like to support domestic or at least continental/western manufacturing. You can’t always tell the materials used (some tell you, others don’t). It does seem to be that a good brand name gets a premium as you would expect. But there are, for instance, Marshall cabs at all the price points.
V Boutique USA will customize one to your requirements at a decent price. https://www.vboutiqueusa.com/
 

redking

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I bought a great head cabinet from a guy on ebay for a very reasonable price - he sent it to me unfinished and I did the tolexing myself. Worked out very well and he was fantastic to work with.

 


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