Un-matching sensitivities

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You know the old joke line, "You can't get there from here"?

Esp with the sub driver being the louder one, the sensible way in 2019 is DSP, electronic crossover, and bi-amping and you will be very happy with the result.

With a passive crossover, using an auto-transformer will work if anybody knows where you can buy an affordable one.

Esp with a BR, other manipulations of the power are "a bridge too far" since they will impair the damping control the amp exercises on the sub driver and you will not be happy with the result.

B.
 
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You know the old joke line, "You can't get there from here"?

Esp with the sub driver being the louder one, the sensible way in 2019 is DSP, electronic crossover, and bi-amping and you will be very happy with the result.

With a passive crossover, using an auto-transformer will work if anybody knows where you can buy an affordable one.

Esp with a BR, other manipulations of the power are "a bridge too far" since they will impair the damping control the amp exercises on the sub driver and you will not be happy with the result.

B.
To my question, you guess I am no electronician at all.
What Esp means ?
But from your answer I understand the compensation could be done with an autotransformer somewhere on the amp output, if not the woofer would be louder and the amp won't work correctly as the damping factor would be modified.
Keeping passive crossover, the sensivities must match.
Do I understand correctly ?
 
"Esp" is just shorthand for "especially".

You are mostly there yes. Normally you want the tweeter to be louder (or match subwoofer) because it's relatively easy to lower the sensitivity of the tweeter with some resistors. Technically you can use resistors to lower the sensitivity of the subwoofer too, but they require massive resistors and a significant voltage division and are just not a good idea.

If you do it with an autotransformer, it is essentially just another component in the crossover. It's a single winding transformer that will drop the voltage. The amp and woofer would still work just fine without an autotransformer, but the volume mismatch would make listening unpleasant as the bass will drown everything else out.
 
Are those sensitivities before or after accounting for the bafflestep?
If before, and you have the flexibility to set your crossover at the bafflestep frequency, you may have a better match than you think.


I am talking before David, these numbers taken from the spec sheets.
The idea behind my initial question is that I lose sensitivity generally speaking, which is detrimental to low listening that I appreciate and may be the amp do not give its best as well under these conditions.
 
The simplest way is putting a resistor in series with the woofer (The resistance can be incorporated in any series inductor), but this changes the Q of the driver & you'd need to recalculate your enclosure.

Alternatively, you could use a 3dB LP filter (an inductor in parallel with a resistor) to achieve a response that slopes down to the crossover point of your tweeter. You need to lose 5dB, so calculate it for just under two octaves below your crossover point. This would give a measure of baffle step, & could be tweaked by adjusting the resistor.
 
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