• New Sponsor: ShipNerd, Ship Your Gear with Us... for less! Click Here.

Thinnest plywood for a 2x12 cabinet

jcs

Member
Messages
8,093
My goal is a very lightweight but strong 2x12 cabinet to use around the house.

I have a lot of extra plywood....I want a floating thin plywood like a 50's Fender cabinet.

Cosmetics are not an issue.

I have several pairs of 50's alnico 12's that I will use that are lightweight.

The cabinet will be a 50's style Fender semi open.

What is the thinnest plywood I can use providing I do some bracing to the corners?
 

Blaqhat

Member
Messages
1,505
I would think as thin as would hold the speakers in place, and provide a baffle from front and back. I'm sure 1/4" plywood would work, but my guess the bass would be overwhelming and undefined. I use only 3/4" for my cabs.
 
  • Like
Reactions: jcs

Whiskeyrebel

Silver Supporting Member
Messages
30,733
I made a 2x12 with 1/2" ply with 2x2 reinforcement on the corners. The baffle is inset about 1-1/2" from the front. It's plenty strong. I wouldn't make a 4x12 that way though because the spans of panel would be more flexible.
 
  • Like
Reactions: jcs

jcs

Member
Messages
8,093
I made a 2x12 with 1/2" ply with 2x2 reinforcement on the corners. The baffle is inset about 1-1/2" from the front. It's plenty strong. I wouldn't make a 4x12 that way though because the spans of panel would be more flexible.
I don't want to use 1/2" for the sides....3/8 or 1/4 is what I am thinking because I already have several 2x12's with 1/2" or thicker top back and sides and yes, they are very similar to what you built overall which works great....too heavy though.

I need much lighter if possible.
 

jcs

Member
Messages
8,093
I would think as thin as would hold the speakers in place, and provide a baffle from front and back. I'm sure 1/4" plywood would work, but my guess the bass would be overwhelming and undefined. I use only 3/4" for my cabs.
I already have several plywood 2x12 speaker baffles I could use that I think are 3/8".

I want to use 1/4" on the top, bottom and sides if possible....maybe 3/8" or a mix of the 2 as I have plenty of extra plywood.
 

jcs

Member
Messages
8,093
Obviously the less deep the cabinet is, the lighter the weight as well.

Any ideas how shallow I can make it, keeping in mind the height will be a bit more than 12" and width a bit more than 24"?
 

jcs

Member
Messages
8,093
Neo speakers?
No but very lightweight alnico 12's from the 50's...no heavy ceramics and the speakers are similar to Jensen P12R...they sound excellent btw.

The pair together weigh 7 lbs.
 
Last edited:

dB

Silver Supporting Member
Messages
4,221
Look at Hard Truckers cab dimensions for their 2x12. It's a surprisingly compact cab. I would think 1/4" could be fine as long as you build it properly.

Aren't 50's Fender cabs made from pine with plywood baffles?
 

jcs

Member
Messages
8,093
Look at Hard Truckers cab dimensions for their 2x12. It's a surprisingly compact cab. I would think 1/4" could be fine as long as you build it properly.

Aren't 50's Fender cabs made from pine with plywood baffles?
Yes they are....however I already have some thin plywood.
 

jcs

Member
Messages
8,093
If I can find some wide enough old pine I could definitely use it but the cabinet needs to be shallow as well to reduce weight.

Not sure how shallow I can go....the speakers are 5 1/2" deep....the cabinet can't be more than 5 1/2" deep and possibly even less.
 

hank57

Platinum Supporting Member
Messages
9,233
I just traded away a pine cab that was 28"w, 19 1/2"h, 10"d and had a baltic birch baffle.
So 10" pine shouldn't be too hard to find you just need it kiln dried I believe. And I'm sure some is more resonant than others.
 
  • Like
Reactions: jcs

jcs

Member
Messages
8,093
I just traded away a pine cab that was 28"w, 19 1/2"h, 10"d and had a baltic birch baffle.
So 10" pine shouldn't be too hard to find you just need it kiln dried I believe. And I'm sure some is more resonant than others.
Don't want 10" deep....more like 6".

I want this cabinet as compact and lightweight as possible but still have some bottom end.

I need to go measure my 62 bandmaster cabinet which originally was a 1x12 tonering but someone made it a 2x12...its closed back though.
 

Geeze

Member
Messages
2,420
You will need to brace the walls similar to an acoustic guitar top with 1/4" material. Otherwise you will probably have resonance issues. Probably you ask? Yep - because you will need to build it to find out. Thin wall speaker cabs have been attempted before and found wanting. There is a lengthy thread at The Amp Garage in the Cabs and Speakers forum a couple of years back. I gathered enough data from that thread to determine I wouldn't be happy with the result and moved on to other projects.

Poplar is easily obtained in wide widths without most of the pine issues [warp, cup. knots, cracking] and the near the same weight as an alternative wood.

I'd also leave any liner application to the last possible attempt to save the project from defeat. It will absorb the sound vibration which for guitar speakers an undesirable thing.

Shallow cabs and bass response do not go hand in hand as the sound wave needs distance to develop. Some of the low frequency lengths are measured in feet.

If you can do it successfully that will be awesome. I look forward to your journey.

Russ
 
  • Like
Reactions: jcs

mickelodeon

Member
Messages
621
I didn't read the responses but here's my relatively informed opinion:

1) use pine instead of ply. Huge weight savings

2) neodymium speakers will be an asset since speakers often weigh more than the entire cab

3) I would never go below 1/2", but look up what forte did with the 3/4". Those channel routs (or even if you did it Swiss cheese style like Gibson weight relief) you could retain the benefits of 3/4" without the full weight
 
  • Like
Reactions: jcs

jcs

Member
Messages
8,093
You will need to brace the walls similar to an acoustic guitar top with 1/4" material. Otherwise you will probably have resonance issues. Probably you ask? Yep - because you will need to build it to find out. Thin wall speaker cabs have been attempted before and found wanting. There is a lengthy thread at The Amp Garage in the Cabs and Speakers forum a couple of years back. I gathered enough data from that thread to determine I wouldn't be happy with the result and moved on to other projects.

Poplar is easily obtained in wide widths without most of the pine issues [warp, cup. knots, cracking] and the near the same weight as an alternative wood.

I'd also leave any liner application to the last possible attempt to save the project from defeat. It will absorb the sound vibration which for guitar speakers an undesirable thing.

Shallow cabs and bass response do not go hand in hand as the sound wave needs distance to develop. Some of the low frequency lengths are measured in feet.

If you can do it successfully that will be awesome. I look forward to your journey.

Russ
Thanks, I likely will not use 1/4" more like 3/8" but keep in mind this is a 50's Fender semi-open with thin floating plywood baffle....but yes, I 'think' I have access to some old pine that is 8" wide, maybe a bit less.

Not a fan of lining any semi open cabinet on the inside....the Rhino liner would be for the outside only but it is VERY tough stuff....though I may not use any coating at all, as this cab is for the house only.

It must be light so I can move it around some but will likely sit on one of my benches off of the floor.

My issue with some of my semi open 2x12 cabs that are 9" deep or more is they can often be OVERLY bassy unless off of the floor.

I am thinking 8" maximum depth.....what do you folks think?
 

jcs

Member
Messages
8,093
I didn't read the responses but here's my relatively informed opinion:

1) use pine instead of ply. Huge weight savings

2) neodymium speakers will be an asset since speakers often weigh more than the entire cab

3) I would never go below 1/2", but look up what forte did with the 3/4". Those channel routs (or even if you did it Swiss cheese style like Gibson weight relief) you could retain the benefits of 3/4" without the full weight
The speakers weigh 3 1/2 lbs. each....this is a cheapie build and these speakers sound great....I may do one baffle with a 10 & 12 as well since I have lots of 10" speakers.

The reason for the plywood is I already have extra 3/8".

The channel routes sound very interesting indeed!
 






Trending Topics

Top Bottom