In Reply to: Altec 806A are 16 ohm compression drivers posted by spkrman57 on January 08, 2003 at 11:45:53:
One must either measure or model the circuit pretty accurately to know what to expect here. To calculate response requires making a virtual circuit of the Altec horn (including the compression driver). In the old days, the best way was to plot a bunch of points by hand, but nowdays it's much easier to do with computers using a program like Spice.You may be surprised at the response curves given when a filter is in the presence of reactive loads. A purely resistive load will provide damping for the filter to provide the smooth rolloff you expect. But a complex load having both resistive and reactive components will modify the filter pretty substantially. And the loudspeaker itself is a complex load, which the compensation circuit modifies. The bottom line is that the loudspeaker is an integral part of the filter circuit, and all components are inter-related. So you'll need to analyze the circuit in more detail to know its response.
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