[xxxxxx]

so nobody has heard the speakers in the link?


http://www.theaudioinsider.com/produ...d28f98c30133d6




"Trevor Wilson" wrote in message
.. .
Soundhaspriority wrote:
"George M. Middius" cmndr _ george @ comcast . net wrote in message
...

Soundhaspriority said:

It does sound exactly like the White Van stuff. The shipping weight is
72
lbs for the pair. That means that each speaker weighs around 30 lbs.
This is
featherweight. It's impossible to make an inert cabinet that light.
Oh really?
http://www.bytesizedreviews.com/index.php?rev_id=39

They're fleecing you

Just my intuition, since I'm not a speaker designer, but I get the
impression that the sound pressures inside a speaker cabinet, at mid-bass
and below, require very dense material. MDF is actually said to be better
than plywood, because it's denser. The stuff you mention above is a sound
absorber, but I don't think it can achieve the inertification of a
speaker cabinet by itself.

**"Inertification"? Nice. Points:

* "Pressure" is rarely an issue.
* Vibration reduction is the key.

Many years ago, Celestion with it's SL600 speaker system showed that heavy
cabinets were not necessary for good reporduction. They used stuff called
"Aerolam". Very light, very rigid and very non-resonant. The advantage of
a low mass cabinet material is that if it does start to resonate, then it
is easy to stop it from doing so. Heavy material require more damping.


With only a very few exceptions, descriptions of speaker anatomy I've
seen describe the cabinet in terms of eithe MDF, or more sophisticated
composites, but the layers are very dense.

**Indeed. Composites are my favourites. So-called 'constrained layer'
construction works very well. Something like a laminated car windscreen,
where you have two rigid layers, separated by a 'squishy' layer. The
squishy layer dissipates (theoretically) any vibration. I proved the
theory to myself back in the early 1970s. I built some T-line enclosures
(from Bailey designs) out of 3/4" chipboard. I used them for about a year
and was happy. I then decided it was time to make them look nice, so I
glued laminate to them. The sound improvement was astonishing and
completely unexpected.


I use something like the "fleece" in my computer cabinets. It's a
composite of two different density foams. It seems to take the edge off.

**I like sheep's wool, but it is expensive. Far more absorbent than
man-made fibres.

Trevor Wilson

--
Posted via a free Usenet account from http://www.teranews.com