It's not like you can't do the same thing either way if you start from scratch, but it does come down to how. Therefore when you want to slip it into an existing crossover you could expect some tendencies.
For example, the L-pad can be used to give control over the impedance which the circuit sees. How high or low that is affects the damping of the circuit for a given set of component values, or a change in values for the same damping. The Lpad also tends to do more to flatten the impedance at the speaker.
For example, the L-pad can be used to give control over the impedance which the circuit sees. How high or low that is affects the damping of the circuit for a given set of component values, or a change in values for the same damping. The Lpad also tends to do more to flatten the impedance at the speaker.
I assume that, in incorporating the single resistor before the tweeter crossover, your crossover was designed accordingly and is working effectively.
As Allen says, the varying impedance of a tweeter is substantially compensated for by an L pad, resulting in less effect on the crossover function.
You could try it, but there's no certainty that removing the resistor situated before the crossover and installing an L pad instead will produce an audible improvement in your case.
As Allen says, the varying impedance of a tweeter is substantially compensated for by an L pad, resulting in less effect on the crossover function.
You could try it, but there's no certainty that removing the resistor situated before the crossover and installing an L pad instead will produce an audible improvement in your case.
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Many thanks. I think I will try it to listen the difference. Other question the 3.6 ohm single resistor attenuate the tweeter approx. 3.2db? For this reason I should try the L-pad with series 2.4ohm/parallel 18ohm according to the L-pad calculator? Is it necessary to keep the values precisely or can experiment with fx. 2.2ohm or 2.7ohm maybe 3ohm?
For parallel I have only 22ohm at home, also good?
For parallel I have only 22ohm at home, also good?
The resistor values don't have to be as precise as those shown in the calculator.
Normally, you would choose the nearest standard values.
In your case, if you must use a 22 ohm shunt, I recommend you go for the 3.0 ohm series resistor, giving a similar percentage increase in both of the calculated values.
Normally, you would choose the nearest standard values.
In your case, if you must use a 22 ohm shunt, I recommend you go for the 3.0 ohm series resistor, giving a similar percentage increase in both of the calculated values.
I'd be interested to see the phase response difference between the single series resistor and l-pad. I'm willing to bet the l-pad is better in all respects since it gets closer to original response through maintaining the original impedance curve as closely as possible. Also, on a mid driver with a lower xover, placing a series resistance followed by a LP filter tends to change the filter Q along with the midrange driver dampening around its fundamental enclosure resonance and not in a good way. In a passive xover I would only attenuate a mid with the addition of a prallel LCR to dampen the mid driver resonance along with running a zobel. The parts cost of a passive midrange filter network with LCR and zobel can spiral out of control quickly.
Going by karoly's response, I think that listening tests are the order of the day.
Thank you for the lot comments. Tomorrow, on Monday I will do a listening test to be sure with the L-Pad. I feel the L-Pad will be better. I will try with 2,2ohm/22ohm and 2,4ohm/22ohm version. Those are very good value combinations.
The 3 elements high-pass filter I created on my own and completely tuned by ear. I tuned until I could feel that it is perfectly blend with the midrange and of course listen to the speaker globally and hear how coherent is.
The 3 elements high-pass filter I created on my own and completely tuned by ear. I tuned until I could feel that it is perfectly blend with the midrange and of course listen to the speaker globally and hear how coherent is.
Just a question. At this moment the 3.6ohm resistor is before the high-pass. According to the online L-pad calculator shows 3.23db attenuate if the resistor is right next to the tweeter. But this 3.23db also the same if the single resistor is before the high-pass? Or the attenuate is different in different position? This an important question in order to choose the right values for the L-pad. So the attenuation have to be the same with either single resistor before the high-pass or with L-pad after the high-pass. Maybe have to be this is an experiment 
That's a good question, to which I don't have a definitive answer! Perhaps Allen does?
All I know is that a single resistor after the crossover affects the crossover frequency and so affects the choice of crossover components.
It takes us back to what was alluded to earlier - all the components are interactive and that's why simulation is so useful.
Let your ears decide. Happy experimenting!
All I know is that a single resistor after the crossover affects the crossover frequency and so affects the choice of crossover components.
It takes us back to what was alluded to earlier - all the components are interactive and that's why simulation is so useful.
Let your ears decide. Happy experimenting!
I only made the right side to compare with the left. I used 2.2ohm/22ohm like -2.8db. The tweeter still laud but I can hear the difference immediately. Then I put 2.4ohm/22ohm, still need more attenuate. It seems the -3.23db could be the same everywhere so need 2.4ohm/18ohm version maybe 2.7ohm/18ohm.
Single resistor before the high-pass: Shows a lot lower treble and has a rolled off top end. It is a bit dampened sound but full-bodied and globally warm in the same time. It rather has smooth charasteristics. Blend very good with the midrange.
L-Pad with 2 resistors (1 serial/1 parallel) right next to the tweeter: Very opened and extended frequency response with full top end. Much clearer, transparent sound and the tweeter shows its full charasteristics. The lower treble disappeared and globally became thin, a bit cold and clinical sound has. The blending with the midrange is worse, like there is a small gap somewhere. The crossover values seems not good anymore.
I think I will install also the left side, will make a longer listening test and make another conclusion. Better to listen in stereo image.
I will also change the cap+coil values to match better with the midrange.
Single resistor before the high-pass: Shows a lot lower treble and has a rolled off top end. It is a bit dampened sound but full-bodied and globally warm in the same time. It rather has smooth charasteristics. Blend very good with the midrange.
L-Pad with 2 resistors (1 serial/1 parallel) right next to the tweeter: Very opened and extended frequency response with full top end. Much clearer, transparent sound and the tweeter shows its full charasteristics. The lower treble disappeared and globally became thin, a bit cold and clinical sound has. The blending with the midrange is worse, like there is a small gap somewhere. The crossover values seems not good anymore.
I think I will install also the left side, will make a longer listening test and make another conclusion. Better to listen in stereo image.
I will also change the cap+coil values to match better with the midrange.