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Hi Lowell.
My "Saturday night emergency solution" comes from the fact that one of the main reasons for using a steep highpass crossover, beyond flat response and all that jazz (which I very much doubt in a *bass* cabinet) is to keep harmful frequencies away from the tweeter.
To be more precise, no real-world crossover is a "brickwall" , passing "everything" above certain frequency and "nothing" below it.
In practice, frequencies "higher than" pass lightly attenuated and "lower than" pass with progressively higher attenuation.
Since usually tweeters are more efficient than woofers and can overpower them, often some extra attenuation is added, such as your L-Pad.
In an emergency (Murphy's Law states things fail precisely on Saturday night, house full , 10 minutes before the show) I guessed the "much smaller cap " solution.
You are right, 1uF into 8 ohms works out as around 20KHz ... at -3dB, the conventional "crossover point".
It also means -6dB at 10kHz, -12dB at 5kHz and -18dB @ 2500 Hz., because it's a somewhat poor, simple, 6dB/oct crossover (definitely no brickwall here)
And what would a proper 5kHz, 18 dB/oct crossover do? (which is much better but still no brickwall)
Beyond the obvious -3dB @ 5KHz, would you believe -18dB @ 2500Hz?
Hey !!! maybe we can save the bacon tonight and do the proper repair on Monday !!!
From JPB's linked site, I also find 0.15mH (150uH) a sensible value, consistent with an around 6KHz , 18dB/oct highpass, so order one and finish the repair properly.
Good luck.
My "Saturday night emergency solution" comes from the fact that one of the main reasons for using a steep highpass crossover, beyond flat response and all that jazz (which I very much doubt in a *bass* cabinet) is to keep harmful frequencies away from the tweeter.
To be more precise, no real-world crossover is a "brickwall" , passing "everything" above certain frequency and "nothing" below it.
In practice, frequencies "higher than" pass lightly attenuated and "lower than" pass with progressively higher attenuation.
Since usually tweeters are more efficient than woofers and can overpower them, often some extra attenuation is added, such as your L-Pad.
In an emergency (Murphy's Law states things fail precisely on Saturday night, house full , 10 minutes before the show) I guessed the "much smaller cap " solution.
You are right, 1uF into 8 ohms works out as around 20KHz ... at -3dB, the conventional "crossover point".
It also means -6dB at 10kHz, -12dB at 5kHz and -18dB @ 2500 Hz., because it's a somewhat poor, simple, 6dB/oct crossover (definitely no brickwall here)
And what would a proper 5kHz, 18 dB/oct crossover do? (which is much better but still no brickwall)
Beyond the obvious -3dB @ 5KHz, would you believe -18dB @ 2500Hz?
Hey !!! maybe we can save the bacon tonight and do the proper repair on Monday !!!
From JPB's linked site, I also find 0.15mH (150uH) a sensible value, consistent with an around 6KHz , 18dB/oct highpass, so order one and finish the repair properly.
Good luck.
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