I simulated both driver in their position on the baffle size I have in mind now, looks like this now
Can you point me in the direction what I need to work on, to achieve better directivity?
Can you point me in the direction what I need to work on, to achieve better directivity?
what is your baffle size?
I was getting mainly problems in vertical. some horizontal
things got easier using 3rd order Butterworth.
your mainly look at how much the woofer rolls off at
whatever you feel is necessary -40 / -60
and that will tell you where the tweeter needs to start.
then with accurate measurements or sim.
you will see if the phase response is going negative or positive.
or how close in frequency it rises and falls.
I can set you up with with some 0 to 90 FRD files on your baffle.
far as attaching them to a post easier to do with text based files.
virtuix cad can open text files, just need to set file type to text
when yah load them.
I was getting mainly problems in vertical. some horizontal
things got easier using 3rd order Butterworth.
your mainly look at how much the woofer rolls off at
whatever you feel is necessary -40 / -60
and that will tell you where the tweeter needs to start.
then with accurate measurements or sim.
you will see if the phase response is going negative or positive.
or how close in frequency it rises and falls.
I can set you up with with some 0 to 90 FRD files on your baffle.
far as attaching them to a post easier to do with text based files.
virtuix cad can open text files, just need to set file type to text
when yah load them.
My baffle size is 200x300 (Width x Height) but like I said my simulations already use those dimensions with the drivers in their intended placement (woofer on the bottom, tweeter on the top). But if you want to set me up with some files, feel free to do so, maybe there is something wrong with my calculations.
Would be easiest to download if you pack the text files into a zip/rar.
I'll try out your tips and look what I get
The 10 ohm and 25uF should preferably be across the woofer, not the system.
If all it does is flatten the system impedance, then it really is overkill and not needed.
If all it does is flatten the system impedance, then it really is overkill and not needed.
Just curious what the bump at 5.5kHz is for the woofer. Ya, in the stop band, and already -12dB, but just wish to learn.
Actually this happens to almost all woofer's that are somewhat larger in size, as far as I know. Not only paper cones show this behaviour, it is very obvious with aluminium cones, just take a look at the response graph of a RS180 vs a RS180P
Ya. I've always heard paper cones can help dampen resonances such as these, but apparently, not always the case. The frequency looks very high too, but that works in our favour because it is easily pushed well into the stop band. I am not sure if it is still worth a notch filter to tame. Thanks.
An amplifier shouldn't have a problem with this. There are some outlying examples where it can make a small difference. I would normally wait until I'm settling on a design and have some free time before experimenting with an LCR across the peak. Sometimes you won't hear a difference and can forget it.
It used to be more common though, when amps weren't so like an ideal Voltage source. I still use amps like that but that was quite some time ago.
Interesting
I started out with large 12" and 15" pro audio drivers.
So cone breakup was part of the game.
And impedance curves were designed to be rather friendly
at 16 or 8 ohms for tube amps.
When they said the amp was 100 watts the amp was 100 watts
from 16 to 4 ohms...LOL
summing was flat and the impedance curve never over 30% of the tap
Paper cones can be a good choice when you have to play close to breakup, such as when crossing to a waveguide but you have to be specific.
This doesn't mean you can play through breakup. Flattening a peak does not fix it. The problem is not the size of the peak because that's easy to deal with electrically.. it's the axial performance.
To clarify... I have never used a paper cone so I didn't know if cone breakup can be ignored. (Especially OP's xover didn't seem to have anything addressing it, like a notch filter.) All I know is if this were a metal cone driver I had to suppress it.
Using your simulation I have come up with the following:
Directivity looks way better now, not too sure what I have done wrong in my calculations. Gonna have to go through the tutorial again haha
Also followed @AllenB's advice and removed the impedance compensation
I personally wouldn't even try to flatten the impedance curve, but that's just because I use only modern amps with high damping factor. I've seen/heard a McIntosh transformer amp that is very expensive but with a low damping factor of like only 40, in which case this curve may cause a very slight frequency response deviation. Or those tube amps which may have even lower damping factors.