Here's the easy way to calculate resistances in parallel--use this http://www.1728.com/resistrs.htm site. Lots easier than having to use one's brain.
Speaker systems do NOT sound good when connected in series. I believe it has to do with all the signal driving the 2nd system having already run thru the 1st system's crossover. (However, it's plenty OK to connect drivers in series.) Connect the systems in parallel.
Lower impedances do not tend to cause amplifiers to oscillate, but one does need to be careful about the amp running out of current. That will happen only if you're trying to drive a quite-lo-impedance load quite loudly.
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Speaker systems do NOT sound good when connected in series. I believe it has to do with all the signal driving the 2nd system having already run thru the 1st system's crossover. (However, it's plenty OK to connect drivers in series.) Connect the systems in parallel.
Lower impedances do not tend to cause amplifiers to oscillate, but one does need to be careful about the amp running out of current. That will happen only if you're trying to drive a quite-lo-impedance load quite loudly.
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