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LE15-Thumper
04-17-2005, 01:16 AM
In crossovers like the N1200 and LX5 that use the tapped HF coil.
As you switch in different positions or taps of these coils, you are changing gain, but are you not also changing slope and/ or crossover frequency ? As you decrease to -6db, there is now much more inductance in series with the HF element. Am I right or wrong here ? You crossover geniuses give me your "input"
No pun intended. And please, no distortion with that input :blink:

Dougie
04-17-2005, 02:36 AM
Thumper;

Using an inductor with several taps allow you to change the inductance, hense the crossover frequency simply by changing the tap positions. The slope rate remains the same, 6dB/oct. Remember, one inductor in series with a woofer is a first order, or 6dB/oct crossover period.

Hope I kept it simple and not 2 much distortion:D

Doug

Zilch
04-17-2005, 03:01 AM
Nope, the subject is the inductor comprising the 2nd pole of the high pass section. The frequency remains the same, since, with respect to the driver, it's merely behaving as a tapped autotransformer; the total inductance, and hence the rolloff frequency, is constant.

http://audioheritage.org/vbulletin/showthread.php?t=5376&highlight=Autotransformer

http://audioheritage.org/vbulletin/showthread.php?t=846&highlight=Autotransformer

The detailed analysis considers the contribution of driver inductance in parallel, as well....

Dougie
04-17-2005, 03:28 AM
Whoops, I should have looked at the N1200 crossover first. I was still thinking simple crossovers from earlier today in another thread started by thumper and jumped to conclusions......hate when I do that:banghead: Must be tired after working 13 hours Friday nite, 4 hrs sleep then driving almost 700 Kms last nite:drive:

Doug

4313B
04-17-2005, 09:26 PM
In crossovers like the N1200 and LX5 that use the tapped HF coil.
As you switch in different positions or taps of these coils, you are changing gain, but are you not also changing slope and/ or crossover frequency ? As you decrease to -6db, there is now much more inductance in series with the HF element.LX5

4313B
04-17-2005, 09:35 PM
N1200