Impendance - Resistance & the story of "Z"

I am intrigued by Sean's observation that complex crossovers, designed to flatten impedance curves, tend to suck the life out of the music. The man is always loathe to name names, but would anyone care to identify some speakers with very simple crossovers or no crossovers at all? In addition to single-driver designs, of course.

I know that some of Israel Bloom's past efforts used very simple "crossovers" ( if you want to call them that ). They are the first that came to mind. This is not to say that i agree with all of the design strategies used in those products, because i surely don't. I'm sure that others can fill in some of the blanks here. Sean
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Sen - good job, however mentioning characteristic impedance is also useful. For low-frequency analog signals, impedance is important, because is represents AC resistance. For high-frequency signals, a phenomenon know as characteristic impedance comes into play. It is defined as SQRT(L/C). Characterisitic impedance is a single number that represents the resistance and matching property of a transmission-line to a system, including a terminator, connectors, line drivers and cables. If such a system is matched impedance, no high-frequency reflections will occur anywhere in the system.

Audioengr: You've hit the nail on the head. When all your impedances match, you don't have reflections. You also get rid of ringing due to the lack of stored / decaying energy in those reflections. The differences in transparency and liquidity can be staggering. That is why i've stated many times before that people that think that transmission line theory in RF applications don't apply to audio circuits / installations have never taken any measurements or even listened to an impedance matched system. With such useful tools as a high resolution scope, spectrum analyzer and a TDR ( Time Domain Reflectometer ), one can basically see EVERYTHING that is going on in the circuit. Sean
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