@presscot
If you ignore distortion and excursion limited output, and power handling then yes. The final slope is the combined acoustical + electrical output and Fs doesn't really come into the math. Unfortunately we should not ignore them. Fs is usually a good indicator of where the knee in the distortion curve could fall, so the rule of thumb of crossing at 2x Fs (or 3x) usually works. If we ignore distortion and output above 1 watt (2.83V) then yes, the correct slope is the combined acoustical + electrical output and Fs doesn't really come into the math.
IOW, crossing a tweeter higher increases the maximum linear output and lowers distortion.
@presscot I kind of want to re-word my reply.
You do not use Fs to estimate the final driver response. At all. XSim for instance has no place to Fs into it because it doesn't affect any of the output charts. The frequency response of the driver plus the transfer function of the crossover will add up the same way no matter where Fs is. This perspective however fails to take into account power handling and distortion or maximum linear excursion (Xmax).
Fs is not a direct measure of either power or distortion but kind of an indirect indicator. Sadly most drivers are not supplied with distortion charts, or max SPL vs. Frequency so for that reason many of us resort to using Fs as a guide, though the max SPL can be estimated from the driver parameters.
I'm blowing away some serious cobwebs here, but I believe we are on the border of discussing what was called "small signal" vs. "big signal" analysis. Small signal being what is true and important at a few volts.
You do not use Fs to estimate the final driver response. At all. XSim for instance has no place to Fs into it because it doesn't affect any of the output charts. The frequency response of the driver plus the transfer function of the crossover will add up the same way no matter where Fs is. This perspective however fails to take into account power handling and distortion or maximum linear excursion (Xmax).
Fs is not a direct measure of either power or distortion but kind of an indirect indicator. Sadly most drivers are not supplied with distortion charts, or max SPL vs. Frequency so for that reason many of us resort to using Fs as a guide, though the max SPL can be estimated from the driver parameters.
I'm blowing away some serious cobwebs here, but I believe we are on the border of discussing what was called "small signal" vs. "big signal" analysis. Small signal being what is true and important at a few volts.
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