Anybody ever cut a Plywood back for their Marshall Cabinet?

[MetalManiac]

I am cutting a plywood back for my 80's JCM Marshall cabinet.
Its sort of a 60's cabinet project, in that I'll be running two new reproduction heritage G12M-20 replicas, along with a couple of old G12-25's to balance the sound with some vintage flavor.
I'm just using deck grade plywood, although hope to get some expensive voidless Baltic Birch eventually.
I was concerned about the plywood, till i took a close look at the particleboard back- theres nothing special about that!
I'm also using some under carpet foam insulation on the plywood back, and put some metal handles on sides of the JCM cabinet .
Closest I'll probably ever get to an old 60's G12m-20 cabinet! haha
Plus, the grillcloth is brown, and sort of looks like the old Marshall grillcloth, and I put an old Plexi cabinet logo on it.
I'm thinking this will be the cabinet for my Plexified Traynor Bassmaster .

 

[JOLLY]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

I bet you were always the first one out in a spelling bee.

 

[the guy who invented fire]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

I bet you were always the first one out in a spelling bee.

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

I rebuilt the bottom half with Baltic Birch from Rockler I believe, after I destroyed it trying ot put in new casters the wrong way;

New Metal handles I got from Mojo I think . carefull some will not fit at all!;

Plywood back I cut, and under carpet insulation glued down with carpet glue;

Plywood back on the cab. No way can this be worse than the particlebaord crap on a JCM. I'm leaving the original particleboard back on my all original 3 other 70's/80's JMP/JCM cabinets ( checkerboard G12h-30 , Black cloth G`12-65, and Green Tolex G12-25 blackback) though.;

Back fits extremly tight. I do need to make a center brace for the cabinet, but not sure how yet. Also looking to put some damping stuff like the automotive damping stuff on the metal handles so they won't ring.

 

[whatshisname]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

It makes a pretty big difference, IMO. Another thing you should do, is seal around the handles with caulking. If you'd like, you can also do all around the rest of the seams, too. The plywood back is the one that really matters, though.

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

just found out this whole stupid thing I did was an exercise in futility.
I found out There is actually nothing wrong with particle board baffles and backs. Particle board is stiffer than plywood, so it actually does a better job of not resonating from speaker vibrations. When properly engineered, it is a solid choice.

I do think that once I get some quality Baltic Birch, this will sound better than a particleboard back though , because those resonances will be a good thing.

 

[Lucid_Lunatic]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

You need to throw that piece of shet back in the dumpster you found it in.

 

[the guy who invented fire]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

This is the funniest thing I've read in months...

come on man...keep going!

 

[xxxplorer]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

pcorn::18:

 

[JOLLY]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

just found out this whole stupid thing I did was an exercise in futility.

You should be accustomed to that since just about everything else in your life is like that as well.

 

[Jessie's ghost]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

just found out this whole stupid thing I did was an exercise in futility.
I found out There is actually nothing wrong with particle board baffles and backs. Particle board is stiffer than plywood, so it actually does a better job of not resonating from speaker vibrations. When properly engineered, it is a solid choice.

I do think that once I get some quality Baltic Birch, this will sound better than a particleboard back though , because those resonances will be a good thing.

Okay, but it has to be 14-ply void-free Baltic birch plywood. Made in America. Or else it will sound terrible.

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

You should be accustomed to that since just about everything else in your life is like that as well.

Whatever Jethro.

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

Okay, but it has to be 14-ply void-free Baltic birch plywood. Made in America. Or else it will sound terrible.

Actually, I was only able to get 11 ply voidless Baltic Birch. Just bought it right now.
Actually a pretty good deal though for anyone wanting to try it- less than 50 dollars.
Let the Clowns laugh, i'll be the one with the amazing sounding 60's Marshall Plexi sounding cabinet. Don't know where it was grown , but it comes form the great state of Missouri, and thats good enough for me.;


http://rover.ebay.com/rover/0/e1105...em=170138095232&ssPageName=ADME:X:RTQ:US:1123

 

[Mr 9finger]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

You bought plywood off Ebay? Don't you have a home depot or lowes near you? They sell the same stuff cheaper and most of them will it to whatever size you want. I took the measurements off the mdf back panel on one of my cabs and Menards cut it for me for $18. For cabinet filler, go to Wal Mart and get some of the poly fill stuff they use for pillows. It's like $2 a bag and works great in speaker cabinets.

 

[Jessie's ghost]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

Let's try to remember that we're talking about giant paper midrange drivers in flimsy plywood boxes. Don't undermine that.

 

[aleclee]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

Let the Clowns laugh, i'll be the one with the amazing sounding 60's Marshall Plexi sounding cabinet.

How much of it is actually going to be from the 60s? A lot of the 1960s material has been removed. You've already replaced half the baffle and the back.

 

[the guy who invented fire]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

Man this crap is priceless...keep on keepin on my man!

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

Man this crap is priceless...keep on keepin on my man!

like I said, let the clowns laugh...
(I suppose HE has a 1960's G12m-20 Plexi era cabinet)

I'm doing the best I can to get an approximation of the prohibitively expensive and rare 60's Marshall cabinet sound and all the clowns can do is walk around on their clownshoes laughing and doing silly stunts.

He who laughs last, laughs best. I'll be the one with the badass sounding basketweave style cabinet.
OOOhh yeah..We bad!

 

[Varg]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

I dont get it. Youre not even in a band, youre a bedroom player, playing Agiles and fake Taiwanese Jacksons, why would you need a 4X12 speaker cabinet and why would you be anal about the back on it since no one else will even hear it?

 

[MetalManiac]

Re: Anybody ever cut a Plywood back for their Marshall Cabinet?

I dont get it. Youre not even in a band, youre a bedroom player, playing Agiles and fake Taiwanese Jacksons, why would you need a 4X12 speaker cabinet and why would you be anal about the back on it since no one else will even hear it?

Tell you waht Vag, why dont you get a couple decades more playing experience under your belt, and about 20,000 worth of some of the finest vintage and modern gear money can buy, and then come back and try and tell me something about how to play and what to play it with..MMkay?