From: DPierce@TheWorld.com (Richard D Pierce)
Subject: Re: Cancel speaker resistance?
Sender: firstname.lastname@example.org (Mr Usenet Himself)
Date: Mon, 16 Sep 2002 12:25:10 GMT
Organization: Professional Audio Development
X-Newsreader: trn 4.0-test72 (19 April 1999)
In article ,
Boris Mohar wrote:
>>Why would one want to do that? Well, getting the Q low enough in
>>a driver can be expensive, because it means, generally, a bigger
>>magnet, and the magnet is the most expensive component in a
>>driver, for the most part. Now, if you were designing an
>>integrated speaker/amplifier, and were constrained by budget or
>>size, then such a scheme might make sense.
> How would one separate the dc resistance of the coil from the from the
>resistive total component of the speaker impedance. The total resistive
>component being the dc resistance of the speaker in parallel with the
>resistances due to the actual acoustic power radiated by the speaker?
In the case of direct radiator systems, the resistance
corresponding to the resistive part of the radiation impedance
(in other words, that part of the speakers circuit that actually
results in sound) is SO small compared to all the rest of the
impedances that it essentially plays a very insignificant role
in the reflected electrical impedance of the speaker.
Consider, for example, that it is not at all unheard of for a
direct radiator system to have an efficiency of less than 1%.
You could reasonably deduce from that the the resistance
responsible for producing sound is less than 1% of the total
dissipative losses of the system.
Without a doubt, the electrical resistance is, by far, the
largest single dissipative element in a direct-radiator system,
follwed nest by the frictional losses in the suspension. WAY
down the list is the radiation resistance.
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