[Hallicrafters] RE: Why is the R-42 speaker so expensive?

[Bob Young]

Cabinet design has a huge impact on the sound of a speaker. A bass reflex 
cab is tuned somewhere at or above the resonant frequency of the driver 
inside, they are much more efficient and have much better bass response than 
an open back cab with the same driver. These cabs take the back wave of the 
driver and put it in phase with the front wave and release it through a port 
usually below the speaker in front reinforcing the bass. Open back cabs 
cancel most of the lower bass because the back and front waves are out of 
phase with each other, ever listen to a driver that is not in a case, no 
bass at all due to out of phase cancellation. The only draw back to a bass 
reflex speaker is they drop off rapidly below the resonant frequency of the 
port. Sealed speakers sound even better as their drop off is much more 
gradual, but they are less efficient as they pretty much keep the back wave 
right in the cab itself. Many different cab designs. I don't know if this is 
anything to do with the price however.

Bob
KB1OKL

Message: 4
Date: Sat, 29 Sep 2007 18:42:17 -0700
From: Julian Bunn <Julian.Bunn at caltech.edu>
Subject: Re: [Hallicrafters] Why is the R-42 speaker so expensive?
To: jeremy-ca <km1h at jeremy.mv.com>
Cc: hallicrafters at mailman.qth.net
Message-ID: <46FEFEF9.4020302 at caltech.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

I think the sound is good simply by virtue of the size of the driver.
The cabinet probably has
minimal or no effect on the acoustics, IMHO.

No idea why they are so expensive ... I picked mine up very reasonably
from a chap who
was selling an SX71 and it came with it.

Julian