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04-02-2004, 02:02 PM
suppoase a driver is 8 ohms
two of such drivers are are conected in parallel
its give an 4 ohm load at the freqs they will play
what if add a resistor of 4 ohms to this connection, the net resistance now will be 8

now electrical gain will be 0db
and acoustical gain will be 3 db rite??

does it make sense
does it make it easier for amp to drive the speakers

second question
if two drivers r connected is series is it possible to add a seperate LPF to one of them like say if there are two mids i want to stop one of them at relatively low freq than other
if they r parallel than i can add diff values of cpacitors and inductors
but if they r in series theres one xover so can i stop one earlier

third question
if two mid range drivers are connected in parallel, say 8 ohms which gives u 4 ohm
now when one driver is called off earlier than other then resistance on rest of midrange freqs will be back to 8 ohms rite ??

fourth question
as mentioned in above when one driver stops working the resistance will be doubled and the amp will produce half power and there will be only one driver working at high frqs so net result will be -6db in that region, -3db electrical, -3db acoustical gain???

these r few of my silly questions

04-02-2004, 02:21 PM
Resistance is futile. :-)

04-02-2004, 04:20 PM
yes but doesnt it has a gr8 effect on the amp output ? ohms law?

04-02-2004, 04:57 PM
when you half the impedence you get double the power (approximately) which inturn gives you a 3db increase. If you double the impedence you half the power (approximately) which will give you a 3db reduction.

to answer question three first if you cross one over higher than the other the amp will still see the load through the whole spectrum at 4 ohms. frequency isn't a factor in impedence.

ok second question in series you can use one crossover in the begining of the series to set the higher frequency then after that you can add another smaller crossover to lower the second in the series.

first question if you have two 8ohm drivers in parallel you have 4 ohms, if you put a 4 ohm load resistor in series it will bring it back to 8ohms. if it is connected in parallel then you will have a 3.33 ohm load.

fourth question frequency has no effect on the load. no matter what the driver is a load if it is playing those frequencies or not. the VC still has resistance. if one driver dies in a series connection then you lose everything, but if one coil goes open in a parallel connection then the load will be that of the one driver that is still functioning.