Hello all,
I'm in the midst of tweaking my 3-way crossover and I could use some help. My drivers are an Eminence Alpha 15 woofer, a Mark Audio Alpair 12P midrange and a GRS PT2522 planar tweeter. They are in an open baffle. Here is what I have
I realize having the resistor in series on the woofer is not ideal.
I only had frd and zma files for the GRS but here's the frequency response graph on x-sim
and here's the measured in-room response:
as you can see, there's a dip in the mid-range.
Things I'm thinking of doing:
changing the 68uF cap to the woofer to 33uF to smooth the spike at 250K. Change the 1.1uF cap on the LP filter section on the midrange to 5uF. Increase the values of the resistors on my tweeter L pad.
I tried an L pad on the woofer and it sounded terrible. I didn't have a bunch of values of resistors available for use however. I tried resistors in the 2-3ohm range. What would you recommend to attenuate the bass?
As is, the speakers sound pretty good but I'd love to get them more balanced
thanks!
I'm in the midst of tweaking my 3-way crossover and I could use some help. My drivers are an Eminence Alpha 15 woofer, a Mark Audio Alpair 12P midrange and a GRS PT2522 planar tweeter. They are in an open baffle. Here is what I have
I realize having the resistor in series on the woofer is not ideal.
I only had frd and zma files for the GRS but here's the frequency response graph on x-sim
and here's the measured in-room response:
as you can see, there's a dip in the mid-range.
Things I'm thinking of doing:
changing the 68uF cap to the woofer to 33uF to smooth the spike at 250K. Change the 1.1uF cap on the LP filter section on the midrange to 5uF. Increase the values of the resistors on my tweeter L pad.
I tried an L pad on the woofer and it sounded terrible. I didn't have a bunch of values of resistors available for use however. I tried resistors in the 2-3ohm range. What would you recommend to attenuate the bass?
As is, the speakers sound pretty good but I'd love to get them more balanced
thanks!
The configuration makes a considerable difference, not least when using an open baffle.
You might tune while measuring one driver at a time between each crossover change, or you could import those into Xsim.
If you get it flat and it still doesn't sound balanced, you might consider doing polar measurements.
You might tune while measuring one driver at a time between each crossover change, or you could import those into Xsim.
If you get it flat and it still doesn't sound balanced, you might consider doing polar measurements.
Thanks Allen,
I know that I really am not being scientific about this and should be measuring each driver in the baffle independently. That being said, here are some tweaks I've come up with. I'm new to x-sim and I think I needed to adjust the sensitivity of the tweeter to match the specs, even after uploading the .frd file. Here is the new x-over and the new frequency graph:
I know that this will be different in my baffle but I'm kinda eyeballing it considering the measured frequency response from before
I know that I really am not being scientific about this and should be measuring each driver in the baffle independently. That being said, here are some tweaks I've come up with. I'm new to x-sim and I think I needed to adjust the sensitivity of the tweeter to match the specs, even after uploading the .frd file. Here is the new x-over and the new frequency graph:
I know that this will be different in my baffle but I'm kinda eyeballing it considering the measured frequency response from before
Your Xsim display is a little unusual. Have you separated the system curve from the others?
Also, individual phase might help in general - https://www.diyaudio.com/community/threads/xsim-configuring-the-plot-window.406106/
Also, individual phase might help in general - https://www.diyaudio.com/community/threads/xsim-configuring-the-plot-window.406106/
I would try a 6 and 6db series filter with just the Alpair (no tweeter) and pass them over as low like 80 hz.
With the series filter the big bass is filtered with a big capacitor so its not expensive to filter it that low.
Here more info on this
With the series filter the big bass is filtered with a big capacitor so its not expensive to filter it that low.
Here more info on this
A rarely discussed crossover is the Series Crossover (in contrast to the universally popular Parallel Crossover). It offers considerable advantages especially with a subwoofer and a bass midrange. I used a series passive crossover in the Bitches Brew Live Edge Dipoles (which are featured in the new October 2023 issue of AudioXpress). Here is the schematic:
ABOVE: In a series crossover, you wire the woofer and midrange in series. You short the woofer with a capacitor. You short the midrange with an inductor.
The circuit above is what I used in the Bitches...
ABOVE: In a series crossover, you wire the woofer and midrange in series. You short the woofer with a capacitor. You short the midrange with an inductor.
The circuit above is what I used in the Bitches...
There is more than one way to attenuate the output of a tweeter > SO, it is not actually wrong, but just unusual.
Without having the subtle 'advantage' of parallel resistor damping, there could be a particular sonic reason for the posted arrangement.