Milleron wrote:
> On Sun, 21 Aug 2005 11:36:21 -0700, jim beam <nospam@example.net>
> wrote:
>
>
>>Milleron wrote:
>>
>>>On Sun, 21 Aug 2005 12:55:20 GMT, "B Squareman" <Squareman@none.com>
>>>wrote:
>>>
>>>
>>>
>>>>"SaraKat" <hxckitty@aol.com> wrote
>>>>
>>>>
>>>>
>>>>>Ok I am very sorry for the lack of info I'm just not sure what is important
>>>>>or not. I have a pioneer stereo and speakers. I know that the speakers
>>>>>are find b/c I bought them a month ago b/c the old ones blew and they work
>>>>>in my friends car...we tries just incase. Also I’m not sure how this is
>>>>>relevant to my stereo but yes my car is a Honda, its a 1995 Civic Ex V-Tec
>>>>>and (sarcastically) I know this must be important Curly but my car is a two
>>>>>door!! I don’t have an amp.
>>>>
>>>>Many times people install speakers with the wrong impedance. This bogs
>>>>down the IC amplifier. Usually before you know the IC fries and the only
>>>>replacement is to replace the audio deck or, if you're lucky, just the IC.
>>>
>>>Mismatched speaker impedance can ruin an amplifier? It decreases the
>>>efficiency of the system, but "frying an integrated circuit?" Are you
>>>sure?
>>
>>do the math. how much more current will sink through a 4ohm load
>>compared with an 8ohm load? and what is the formula for power?
>
>
> If I = V/R, then the answer might be twice as much.

yup. and P = I^2.R

> Why am I to
> deduce that this will "fry" the power amp? I'm not trying to be
> argumentative because I have no special knowledge of car audio, but
> I've simply never heard of an impedance mismatch actually damaging
> audio equipment, and the statement didn't seem intuitive to me.

it's not common for normal domestic use because you usually don't get
near the power limits very often, but once you get into a car, where
power is often substantially higher [cranking the stero up to cover road
noise, etc.] and temperature is often much higher, it starts to be a
problem.

>
>>bottom line, yes, wrong impedance can fry the ic.
>
>
> I've run mismatched speakers on home audio systems for years with no
> problems at all. It can mean that you have to turn up the volume a
> little and perhaps the power amp may work a little harder, but it has
> never caused any damage. All the product manuals suggest matching
> impedance if possible, for the sake of improving efficiency, but none
> I've owned over the last thirty years has ever warned that serious
> damage to the receiver may occur from the mismatch.
> Are car audios that much different from home receivers?

as per the above, it's not usually a big deal in domestic systems, but
as you approach the output limit, things get all toasty. chip life
drops dramatically with increasing temp.

>
>
>
> Ron