I have re-capped some Altea-Lansing Bolero 890C speakers. The tweeter has a 6uf cap then a resistor in line which works in conjunction with a selectable L-pad to attenuate the tweeter. This all makes sense, but there is another 3uf cap in parallel with the series resistor. This cap comes after the 6uf cap. I've never seen capacitors in series like this. Again, the order goes 6uf cap------3uf cap and resistor in series to the speaker. Can anyone tell me what this second capacitor is doing and why it might be there?
It sounds as though it bypasses the resistor for higher frequencies. This boosts highs overall. What value is the series resistor?
The resistor is 15ohm, which is a lot. I can't find any info on a "compensated attenuator" that shows this kind of thing. It would make sense if there was a parallel inductor because the crossover would have a steeper slope, but there is no inductor.
I do see that this second capacitor should (by my limited knowledge on this stuff) bypass the resistor and add higher frequencies. I just don't seem to be able to find any info on this and I don't even know if it works that way, but it makes sense if it does.
I do see that this second capacitor should (by my limited knowledge on this stuff) bypass the resistor and add higher frequencies. I just don't seem to be able to find any info on this and I don't even know if it works that way, but it makes sense if it does.
Depending on the resistor value, that parallel cap will boost some highs to the tweeter.
The resistor damps some lower highs, most likely to compensate for tweeter or overall irregularities in the system.
The resistor damps some lower highs, most likely to compensate for tweeter or overall irregularities in the system.
Since the resistor is 15ohm and by my calculations the L-Pad (depending on which parallel resistor is selected) attenuates the tweeter by around 10-16db, if the second capacitor is a smaller value in series then it allows higher frequencies to be greatly boosted. Cool. Can anyone confirm that it works like this?
The 3uF will override the resistor at 3k5Hz and above. This will be gradual, and in the context of the other components it may not be as simple as it seems.
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