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I would put a separate set of resistors on each driver to spread the load. You also want to place the resistors in after the cap/coil. Though you can try a single set out in front at first and check if they heat up at all, if they don't get warm you are probably ok leaving them there.

If I get some time over the weekend I'll see if I can cook up another network that is more efficient then just a regular lpad (waste less power into resistors).
 

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Not by much, I was modeling it the other day. Actually the hf driver is smoother with them after the network.
 

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I dont know if this means anything but I have seen others using VERY steep crossovers when using the BMS coax. Like 56order and so on. That member used a Lake processor for the XO. Maybe useless info here but fogured I would mention it.
 

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Hey Luke! I don't know if you remember me but I stopped by your house probably two years ago to listen to your setup... looks like I need an updated audition! You have given me the sickness and I have built a few different setups since including an 18" sub, which is Tame in your world but blows me away still ha.

I was reading through this thread and noticed there might be a GTG sometime this summer? Let me know if that goes through, i would love to come!
 

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Here is one to try, pads midrange without having the resistors suck all the power from the lower frequencies. Note 4ohm/8ohm l-pad on HF is same on both.






You will have to go in and make some adjustments to the EQ but overall a more linear shape to the response besides a few dips and peaks to take care of with EQ.
 

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the RLC on the midrange is attenuating it by increasing the impedance? if so, what is the advantage/disadvantage of that approach as compared with the L-pad or simple series resistors? I assume with an increased impedance, one gets the attenuation, but without having to dissipate heat from flowing current? if so, why wouldn't that same approach be used on the hf? is it because the amount of current is less and no change in the frequency response itself is desired? and last question, could a similar RLC circuit (but with different parameters) be used to attenuate the bump around 3khz if this were a purely passive design?
 

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Yes, the series RLC network is attenuating level by increasing impedance. It is more efficient then just a series resistor because the capacitor and inductor increase impedance without having to dissipate the current that does flow through them. For this filter imagine the inductor giving a lowpass around 800hz and the capacitor a highpass around 2.5k, the resistor only has to fill in the gap between the two. Another advantage is the minimal reduction in energy below 500hz which is where most of the energy will be wasted if using a series resistor.

It is possible to do something similar with the HF unit but very little energy is in the range above 6k so to me it is not worth the added expense or complexity.

Yes another RLC network (maybe parallel this time) could be used as a notch to knock out the bump at 3k.


Or: https://lh6.googleusercontent.com/-911Y0OzGD3k/VV6vWr8PhMI/AAAAAAAABtU/xir32iQznwU/w1598-h999-no/Full%2Bpassive.png
 

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Discussion Starter #472
Here is one to try, pads midrange without having the resistors suck all the power from the lower frequencies. Note 4ohm/8ohm l-pad on HF is same on both.






You will have to go in and make some adjustments to the EQ but overall a more linear shape to the response besides a few dips and peaks to take care of with EQ.
Is a 2.2mH inductor ok for this? Parts-express doesn't have an even 2mH that I can find.
 

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Here is one to try, pads midrange without having the resistors suck all the power from the lower frequencies. Note 4ohm/8ohm l-pad on HF is same on both.






You will have to go in and make some adjustments to the EQ but overall a more linear shape to the response besides a few dips and peaks to take care of with EQ.
This is for the 8 ohm 4594 correct? I may make a similar XO for my 16 ohm 4594's that I haven't quite tuned in just yet.
 

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Discussion Starter #474
Hey Luke! I don't know if you remember me but I stopped by your house probably two years ago to listen to your setup... looks like I need an updated audition! You have given me the sickness and I have built a few different setups since including an 18" sub, which is Tame in your world but blows me away still ha.

I was reading through this thread and noticed there might be a GTG sometime this summer? Let me know if that goes through, i would love to come!
I remember you. When you were last here, construction hadn't even begun on that room! It's pretty much finished now.

The GTG is definitely a go for 8/1, but you can stop by any time for a demo!
 

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I always keep a PE catalog handy just for the list of crossover part values they stock and their part #'s, much quicker then looking them up online.
 

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Discussion Starter #478
Old crossover:



New crossover:




I KNOW, it's ugly as sin, but it works. Making these things neat and tidy isn't a strength of mine to say the least...lol


4ft indoor response before and after (no EQ):



Current response at the LP after EQ and moving the gains up 6db:




Notes:

1. The hiss is pretty much gone. You can hear it if you're within a few feet of the speaker, but the LP is about 15ft back, so finally non-issue.
2. Response at the LP is smoother with less EQ across the board.
3. Previously, the highs at high volume on certain material could sound a bit "grainy" if you were listening for it. Possibly too much digital attenuation before? Whatever it was, it's gone.
4. Thanks Ryan and Matt!!! Very happy with the results.
 

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Glad that worked out for you.

The results aren't to surprising. You had the important bandwidths buried down in the noise floor of your amps. Now they can play properly.
 
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