How important are the Speaker Cabinets?

There are various ways to skin this cat.

Just as in turntable plinths, one school advocates the addition of mass, in the form of thicker cabinet walls and additional internal bracing, to make the cabinet as rigid as possible. All cabinets resonate, always at more than one frequency, and the goal of this design is to quiet those resonances as much as possible. The addition of mass, usually lowers the frequency of the resonanance and lowers the "Q".

Another design school advocates making the cabinet lighter. The obvious effect is that the resonances, though louder, will be higher in frequency. If they can be moved up in frequency, they are both less bothersome to the ear, and they tend to be of higher "Q". "Q", or quality factor has to do both with how wide the resonance is and how quickly it clears, or stops ringing. Even if the high frequency resonance is louder, if the ear is less sensitive to resonance in this range and the resonance stops sooner, it will have a different sound than the other example, above.

Material is an important consideration in the resonant structure of the cabinet, which is why some manufacturers use exotic materials, such as the aluminum cabinets of the Magicos referred to in the above post. And some use different materials in different parts of the cabinet to spread resonances and to add some degree of economy to the equation.

Although most speakers are made of MDF (medium density fiberboard) which is generally cheap and may be comparable to the cost of some drivers, the labor in constructing and veneering the cabinet is the more significant expense in the finished cost of most speaker cabinets. My guess - and it is just that - is that most cabinets well exceed, by serveral times, the cost of the drivers in them. And this is most certainly true of those with exotic materials and unusual construction techniques.

But in the end, knowing if the eggs are brown or white does not tell you a lot about the finished omlette. Listen without predjudice to various speakers and pick the one that most closely matches the paradigm of live music that exists within your mind.

Hi,

You should have started the thread by asking if speakers need a cabinet at all?
A speaker cabinet is a cheap (if not free) way to produce "bass".
A dipole - open baffle speaker will solve the problem more efficiently. Just save your $30,000 in the Magico Minis and spend more time doing speaker's design research.

Martin.

>I am curious to learn about speaker cabinet design and how important does the cabinet contribute to the overall sound.

It's significant.

>Does the weight of the cabinet make a difference.

Weight and stiffness determine resonance amplitude, with stiffness going up with the cube of thickness. Obviously a thick enough brace will out-do uniformly thicker material but involve higher labor costs.

You really want to limit un-braced lengths enough to push resonances out of the driver pass-bands.

Siegfried Linkwitz has suggested that (mid-range) enclosures shouldn't have over 4 square inches of unbraced cabinet.

>For instance a floor standing speaker that weighs 200 pound versus one that weighs 60 pounds or 300. Is there any correlation to weight and sound? How about material?

All else equal there may be. There's an AES paper which gives an example of cylindrical enclosures (the material is stressed only in tension) being as stiff as 4" concrete which you can (I did that with Siegfried's Pluto design) exploit to build a rigid 15 pound speaker. Open baffle speakers don't have internal pressurization to cause problems so a 60-70 pound floor standing example can be free of cabinet coloration (I did that with Siegfried's Orion design).

>How much are you paying for the cabinet versus the drivers on an expensive pair of speakers?

Depends on construction technique, labor costs, finish. Many large vendors speakers are cut on CNC routers and assembled with miter fold construction. MDF is nearly free, common hardwood veneers are cheap and don't take much to apply to the whole sheet in a veneer press, semi-skilled Chinese workers make a lot of speakers for $150 a month in wages, and the drivers should be more; but most of the price is overhead in terms of advertising costs, dealer profits, dealer overhead, etc.

American labor is pricey. Craftsmen are more expensive than factory workers. Use the Orion+ built by Don Naples at Wood Artistry as an example. You start at around $6800 less $1900 for drivers in small quantities, $500 for cross-over parts, $300 for cross-over labor, $170 in licensing costs, and are left with cabinet costs of $3700 of which maybe $3500 is labor and a screaming deal (California is not cheap).

Larger companies get better deals on drivers (quantity) and labor (factory workers not craftsman) but some really cut corners on drivers. $15-$25K a pair covering advertising, overhead, markups through the distribution chain, maybe amortized engineering costs, etc. is not out of line.

Benifits of a thicker cabinet wall. Better bass definition. Less coloration. Better image since drivers not vibrating on baffle as much as thin cab. To me doubled cabinet walls with bracing are the way to go. MDF is a poor choice baltic birch ply is 1 of the best materials.