Thanks for the detailed clarification, Alan. By the way, I watched all your videos on YouTube last night and they are really useful and practical, thanks a lot!
Now I have a question for Epic Grand Master - 500. Since the center in the package is VP150 but I am kind of intrigued by VP 180. How are these two centers compared to each other in terms of sound quality in a living room about 12*24?
I also noticed that the impedance for VP180 is only 4 Ohms while that for VP150 is 6 Ohms. I've heard that low impedance speaker will lose details and clarity due to high currents. Is that correct? What are the advantages for low impedance speaker?
High current demands can cause speakers to lose detail or clarity. This would be caused by the amplifier or receiver running out power which results in clipping (nasty distortion) coming out of the speakers. As one of the advantages of low impedance speakers is that they can draw more power from the amplifier, the disadvantage is that it can be more demanding on the power supply either causing the electronics to go into clipping more quickly, overheat and possibly shut down. Electronics that have high quality power supplies and lots of headroom will not run into this problem.
Now impedance is only one factor that determines how difficult or easy a speaker is to power. You also have the sensitivity, phase angle as well as the users listening habits (how loud) and room size/listening distance. The speakers specifications are all determined by the designer -# and type drivers, crossover design etc. Sensitivity is self explanatory, the phase angle which is sometimes shown with impedance draws current above what the impedance is at a given frequency. The more negative the phase angle at a given frequency the more current that will be needed to meet the power demands. All in all it is a pretty complex subject that combines many factors.
