Speaker Cabs Part I:  Speaker  Cabinet Materials

Speaker cabinets and head cabinets can be made of variety of materials. Many players never really think about what their cab is made of since most are covered in tolex and the  materials are not obvious. The materials used are important for two reasons: they affect the durability of the cab and they affect the tone of the cab.  The cost of the cab often depends on the materials used. With a little knowledge a you can make informed decisions about cabs.   In this article we will look at the materials used.  Generally cabs are made of one of four materials: particle board, Medium Density Fiberboard or MDF, hardwood plywood, or solid woods.

Particle Board:

What is it?
Particle board is made of sawdust and wood chips that held together by glue.  It's an inexpensive material and easy to machine.  It very dense and heavy. Cabs made with it weigh in on the heavy side.

What Cabs Have It?
 Particle board can be used for all or part of a cab's material.  Particle board cabs are usually found in low quality and low cost amps. You might also see it as baffle material or panel material in certain cabs with other materials for the shell. 
 

How Does it Sound?
Particle board is sonically dead. Hi-Fi people like it because it does not alter the sound, so you just hear the speaker. Guitar players find it to be less lively than other materials because speaker cabs for instruments are sound sources and the wood is used to add to the tone.  However, if you making a non-resonate cab it’s a good choice.
 

How does it hold up?
This where particle board fails. It simply does not hold up well to long term abuse.  Particle board cabs need additional bracing to be sturdy and over time they absorb moisture and fall apart. If you live in dry area or do not travel with cab it will last much longer.  Many later Silverface Fenders use particle board for baffles and front panels of heads. I dread having to remove speakers from particle board baffles because they often crumble.  Gigging musicians will benefit from using a cabinet with a tougher material but for someone plays mostly at home it will not matter.
 

Other considerations:
Particle Board has to be covered since it has no wood grain so tolex, carpet or bedliner type materials must be used. Since it is manufactured in large boards cabs cab be constructed to lots of different depths and sizes.

Recommendation:
I would avoid getting a particle cab if you cab if you care about durability. Lots of low cost amps and cabs are made this way but most players find they do not hold up over time. 

MDF

What is it?
MDF is made of wood fiber pressed in large boards. It has less void space than particle board and is made of smaller fibers.   It's tougher than particle board and is  heavy. Cabs made with it are heavy too.  It's more durable than particle board and easy to work with.
 

What Cabs Have It?
 Many cabs are made with MDF.  Its one of the most common materials for lower end bass cabs, guitar, and pa speaker cabs. It used on lots of heads too. It can be used in the whole cab or as panels for cabs.
 

How Does it Sound?
MDF is sonically dead. Hi-Fi people and bass players people like it because  it does not alter the sound of the speaker but guitar players may find it to be less lively than other materials in a cab meant to be resonant. In non resonant cabs it's a fine material.
 

How does it hold up?
While tougher than particle boards. MDF boards can  absorb moisture and then fall apart but it's much less of an issue than with particle board. It critical to keep them dry.  MDF holds together well so long as the cab has adequate bracing. 
 

Other considerations:
MDF has to be covered since it has no wood grain. Tolex, carpet or bedliner type materials must be used. Since it is manufactured in large boards cabs cab be constructed to lots of different depths.

Recommendation:
MDF cabs are okay and affordable but not quite as durable as a well made Plywood or Solid Wood cab. It is much better than particle board in all respects. 

Hardwood Plywood

What is it?
Plywood sheets are made from layers of thin wood pieces with each ply or layer laid down at a 90 degree angle gain wise.  These are glued together. Plywood can be made of lots of materials but for this discussion we will limit ourselfs to hardwood since pine and softwood plywoods is not appropaite for cab construction. Birch plywood is the most common in cabs.
 

What Cabs Have It?
The majority of upper end cab makers use plywoods.  Marshall 1960 cabs, Hiwatt Cabs, Mesa Cab etc etc are all made of plywoods. They are the industry standard for good cabs! 

How Does it Sound?
Plywoods resonate more that MDF or Particle Board and tend to sound more lively and punchy to the ear. 

How does it hold up?
Plywoods are tougher than MDF and do not have as much of a problem with mosture absortion.  They will hold up well on the road assuming the cab is properly constructed. Plywood tends to be very stable and not warp over time so long as it is not been exposed to too much mosture.
 

Other considerations:
Plywoods have grain so they can be varnished or covered.  Typically they are covered since it is cheaper to cover them and it hides the ply. Since it is manufactured in large boards cabs cab be constructed to lots of different depths. Since it inherently truer than solid wood so it's easier to build with and there is less waste.

Recommendation:
Plywood is good material for cab and I would not hesitate to recommend it's use. Carl's Custom Amps uses plywood for their British Series Amps and certain cabs.

Solid Woods

What is it?
Solid wood cabs are made of real wood! This is not to say they are all made of single piece. Often solid wood is more stable and less prone to warp when a few pieces are edge joined to form a panel.  Pine is the most common material but other species can be used. 
 

What Cabs Have It?
Some high end amps have it. Vintage Fender and other American made amps often used solid pine.  I've made some out of oak.  You will even see some exotic wood cabs.

How Does it Sound?
Solid wood tend to be more lively and resonate than any of the other materials. It adds to the tone of the speaker with pleasing overtones.  The species of wood and it's density affect how it resonates so the tone varies from cab to cab and one piece of wood to another. Much like a guitar. 

How does it hold up?
Solid wood cabs when built well are as tough as the come when built correctly. 
 

Other considerations:
Solid woods can be covered or varnished for natural look. One limitation is that solid wood usually is milled to certain board sizes so cabs are usually not as deep and more commonly used as open back cabs for that reason.  You can edge glue boards to increase width but it is a labor intensive practice. 

Recommendation:
Solid wood cabs are really worth trying out.  They sound great and hold up really well. Carl's Custom Amps uses it for all it's American Style Amps and for others as well. 

Want a Custom Speaker Cab Made?  Contact me!! carlscustomamps@gmail.com. Lots of different configurations, tolexs or finishes, grill cloths are available. Plywood or solid woods.  Loaded with Weber Speakers (www.tedweber.com). See some examples on my gallery page.