Cab gurus...

[Ayrton]

Re: Cab gurus...

Most plywood sold at the big box stores is 4'x8' sheets and advertised as 1/2" or 3/4".

True (Russian or Finish) Baltic Birch comes in 5'x5' sheets only, and is usually marketed by the ply.


3 mm ≈ 1/8″ (3 plies)
6 mm ≈ 1/4″ (5 plies)
9 mm ≈ 3/8″ (7 plies)
12 mm ≈ 1/2″ (9 plies)
18 mm ≈ 3/4″ (13 plies)


You can also get various grades of finish.

What makes BB so special is all the layers are 100% birch with no voids. Apple or cabinet grade plywood is two veneers sandwiched around various pieces of mystery wood.

I get my BB from the local wood supplier.

 

[Gone_Shootin]

Re: Cab gurus...

And the 2x12's

Also, the back aint MDF, it's some other kinda particle board product

Not all the 2x12s. 1936s and a few others aren't MDF or whatever, but the budget stuff is.

 

[Adieu]

Re: Cab gurus...

Not all the 2x12s. 1936s and a few others aren't MDF or whatever, but the budget stuff is.

1936 is LEGENDARY for being ALL-MDF. People raging about paying for a supposedly-topshelf 212 from THE marshall and then finding out it's MDF with 2 chinese speakers has been a regular source of lulz over the years

Some rumors claim they started using plywood again ~2013, but the vast majority you'll encounter in the wild are pure MDF

 

[beaubrummels]

Re: Cab gurus...

In 1994 I bought a JCM900 1960AV, very much like the CL ad with stereo options, but with Vintage30 Celestions in it. Still have it and it’s my number one cab. I gigged it all over the state for about 5-6 years, hauling it in an open bed pickup truck, recorded it in the studio for 10 years, beautifully broken in. Only ever got one small tear in the tolex on the side and the slant corners got a little abrasion from my truck bed. The little plastic corners have cracked but haven’t come off at all. I don’t care what it’s made of. It’s heavy as **** and sounds like a million dollar record. It makes amps sound better than they are.

 

[dystrust]

Re: Cab gurus...

Not all the 2x12s. 1936s and a few others aren't MDF or whatever, but the budget stuff is.

Marshall 1936 cabs aren't MDF now, but they were all-MDF for several years in the early 2000s (maybe even late 90s). I'm not 100% sure when that ended, but Marshall finally listened and newer 1936s are plywood with the LDF back panel just like 1960 cabs made after 1971.

 

[Aceman]

Re: Cab gurus...

Let me ask this - why is MDF a "bad" thing? Other than the perception that it is cheap.

I'm asking because much like acoustics - everyone lost their mind at Ovation. But the reality is the top is like 98% of the tone....So wood top with plastic back.

 

[Adieu]

Re: Cab gurus...

Let me ask this - why is MDF a "bad" thing? Other than the perception that it is cheap.

I'm asking because much like acoustics - everyone lost their mind at Ovation. But the reality is the top is like 98% of the tone....So wood top with plastic back.

1) MDF weighs about 40% more
2) wood and ply builds are intended to resonate, MDF is used in applications for intentionally KILLING resonance... that's what makes it, like flat-EQ speakers, a good thing for intentionally-neutral reference speaker cabs, but not so for guitar cabs. For guitar cabs, the speaker and cabinet are in effect the acoustic extension of the instrument. "Good" speakers and "good" cabinets don't just reproduce the signal, they add color to it.

That's also why MDF is good for bass cab builds, where it's used to combat unwanted vibrations from deep lows in higher wattage scenarios

 

[Darg1911]

Re: Cab gurus...

Most plywood sold at the big box stores is 4'x8' sheets and advertised as 1/2" or 3/4".

True (Russian or Finish) Baltic Birch comes in 5'x5' sheets only, and is usually marketed by the ply.


3 mm ≈ 1/8″ (3 plies)
6 mm ≈ 1/4″ (5 plies)
9 mm ≈ 3/8″ (7 plies)
12 mm ≈ 1/2″ (9 plies)
18 mm ≈ 3/4″ (13 plies)


You can also get various grades of finish.

What makes BB so special is all the layers are 100% birch with no voids. Apple or cabinet grade plywood is two veneers sandwiched around various pieces of mystery wood.

I get my BB from the local wood supplier.

Some of the Russian producers are supplying the Baltic birch in 4'x8' sheets now as well. I don't know about Finland.

 

[PFDarkside]

Re: Cab gurus...

Let me ask this - why is MDF a "bad" thing? Other than the perception that it is cheap.

I'm asking because much like acoustics - everyone lost their mind at Ovation. But the reality is the top is like 98% of the tone....So wood top with plastic back.

Not trolling, but you really think an ovation sounds 98% as good as an all solid Martin, Gibson or Taylor?

This thread is a great resource.

 

[Ayrton]

Re: Cab gurus...

Let me ask this - why is MDF a "bad" thing? Other than the perception that it is cheap.

I'm asking because much like acoustics - everyone lost their mind at Ovation. But the reality is the top is like 98% of the tone....So wood top with plastic back.

Technically dense and consistent MDF is what you want for a speaker cabinet. However, it is not very durable and ill-suited for the abuse a guitar speaker cab would endure on the road.

Engineered wood only started mass production in the early 1980's, and before that Pine and various plywoods were used in cabinets. The construction of the Marshall 4x12 was and remains a result of necessity over preferred acoustics. However, the inefficient design is what gives Marshall (and similarly constructed) cabinets their signature sound. Cabinets built differently (Bogner, Orange, Soldano, etc.) have a different sound.

Everything effects sound, the construction method, the wood used, speakers, and grill cloth.

 

[Securb]

Re: Cab gurus...

I am not going to get into the acoustic properties argument. The bottom line is MDF cabs sound fine. I have a variety of cabs in the house made of every material you could imagine. My No. 1 is a Marshall MX212 with two Eminence Wheelhouse 12s. They are very neutral speakers so maybe they play to the MDF better, I don't know and don't need to know, but I can guarantee if any of you played this cab a smile would be plastered on your face.

 

[Ayrton]

Re: Cab gurus...

Bob, keep an eye out for a Peavey 5150 cab from the '90's. They were literal clones of EVH's favorite Marshall cab right down to the Sheffield speakers. You can find them for around $200.

 

[Aceman]

Re: Cab gurus...

I guess MDF vs wood is all about how much you like the speakers....

Interesting. I can see resonance being a generally worse thing than a good thing in many situations.

 

[Ayrton]

Re: Cab gurus...

Ideally audio speaker cabinets are designed around the efficiency specs of the speaker as to not color the sound. Instrument amps never got that consideration. We all know how the Marshall 4x12 was born, everything since has been some variation of that.

 

[Aceman]

Re: Cab gurus...

We all know how the Marshall 4x12 was born, everything since has been some variation of that.

Ummm - I don't....

 

[Ayrton]

Re: Cab gurus...

Ummm - I don't....

The short version is Pete Townshed asked Jim Marshall to build him a 100 watt version of the JTM45 and a 8x12 cabinet to go with it. You can imagine what they weighed, so after a couple of shows Pete had Marshall cut the cabs in half. The Marshall stack was born.

No real consideration was given to air space or speaker specs. The angled top was purely aesthetics and was carried over once the 8x12 was cut in half.

Found a picture of the original

 

[Adieu]

Re: Cab gurus...

Ideally audio speaker cabinets are designed around the efficiency specs of the speaker as to not color the sound. Instrument amps never got that consideration. We all know how the Marshall 4x12 was born, everything since has been some variation of that.

Well, "distortion" is THE ultimate 4-letter word of PA and audio amps, too... however, faithful reproduction ain't a goal in electric guitar amplification. It's usually downright undesirable.

 

[dystrust]

Re: Cab gurus...

I guess MDF vs wood is all about how much you like the speakers....

Interesting. I can see resonance being a generally worse thing than a good thing in many situations.

For cabs that you're moving a lot, durability and weight are important factors and MDF loses on both counts. (it's heavy and tends to fall apart with abuse)

 

[NegativeEase]

Re: Cab gurus...

OP link is dead -but I see it's a JCM 900 Cab.

Those are cool.

When I would play more often with stacks, I was fan of mixing two 25W Greenbacks for the warm details and crunch with 2 65s or 75s for the bigger punchier sound and feedback.

I used a Marshall Tall Vintage "1960TV" Cabinets.

 

[Aceman]

Re: Cab gurus...

Cab is gone - oh well....

Awesome informative thread though!