Disclaimer. As I value the low cost aspects of DIY and like to keep things simple my previous speaker builds have been utilizing a full range larger driver (and just letting it play) with a first order capacitor in front of the tweeter…..or utilizing an amplifier with a high pass filter with a separate subwoofer amp with low pass with or without DSP.
This is the first time I’m spending more than $19 on a tweeter, and I’d really like to hear it cleanly in its range (testing shows that it plays well with hardly any distortion all the way down to 500Hz). It’s an 8 inch planar/mid.
The 8 inch woofer frequency response looks nice up to 1k. My instinct was to in parallel low pass the 8 inch woofer at 800Hz and in parallel high pass the planar mid/tweeter at 800Hz….but then I thought this might make a hole at 800Hz and my second thought would be to low pass the 8 inch woofer the same; but high pass the planar mid/tweeter at 500hz.
I’ll subsequently post the specs and FR graphs below.
Any advice or commentary is greatly appreciated. Thank you.
This is the first time I’m spending more than $19 on a tweeter, and I’d really like to hear it cleanly in its range (testing shows that it plays well with hardly any distortion all the way down to 500Hz). It’s an 8 inch planar/mid.
The 8 inch woofer frequency response looks nice up to 1k. My instinct was to in parallel low pass the 8 inch woofer at 800Hz and in parallel high pass the planar mid/tweeter at 800Hz….but then I thought this might make a hole at 800Hz and my second thought would be to low pass the 8 inch woofer the same; but high pass the planar mid/tweeter at 500hz.
I’ll subsequently post the specs and FR graphs below.
Any advice or commentary is greatly appreciated. Thank you.
Then, plan B due to creating a hole concern
(Low pass the 8 inch woofer as above…but use this in front of the planar mid/tweeter.)
I’ll add that I’m 51 years old and don’t hear above 15 KHz
(Low pass the 8 inch woofer as above…but use this in front of the planar mid/tweeter.)
I’ll add that I’m 51 years old and don’t hear above 15 KHz
Yes, I’m aware there is a small SPL matching issue….but I really want to hear the planar mid/tweeter (and my high frequency auditory capability isn’t great)…and there’s a subwoofer in the room.
Would be to copy from someone else's design! At least search for what others have used to make it.
Don't bother, as the tweeter can be reduced in level by the means of resistors. Yes, you'll find resistors, coils and capacitors in crossovers.
The HP filter in post #3 I think it's just a capacitor, an electrolytic one. See how math is applied : 600 Hz Fc for 4Ω load and half Fc for Z=8Ω.
Thank you for identifying my pre coffee brain fart.
This would be Plan B in front of the planar mid/tweeter…..with the as above posted 800Hz low pass in parallel in front of the woofer.
This would be Plan B in front of the planar mid/tweeter…..with the as above posted 800Hz low pass in parallel in front of the woofer.
If it’s not a concern; great.
I worried about the slopes of amplitude loss from both drivers at the same 800Hz frequency could potentially create a dip at 800Hz when both drivers are crossed over at the same 800Hz frequency….if the spl amplitude loss slopes for both drivers were steep.
I worried about the slopes of amplitude loss from both drivers at the same 800Hz frequency could potentially create a dip at 800Hz when both drivers are crossed over at the same 800Hz frequency….if the spl amplitude loss slopes for both drivers were steep.
The crossover design ensures that the drivers sum flat at the crossover frequency.
Using your high pass and low pass crossover units results in this overall crossover circuit:
There is no need for the "speaker protector" for the tweeter as the crossover circuit above is already providing that function.
Using your high pass and low pass crossover units results in this overall crossover circuit:
There is no need for the "speaker protector" for the tweeter as the crossover circuit above is already providing that function.
Yes, the Fc is where( graphically, otherwise is 'when') you halve the volume, which corresponds to -6dB. So when you say that the frequency cut is at 800 Hz, it means that at 800 Hz you have half the volume, and the adiacent way meets at that point with the same -6dB, and then acoustically they are joining together to reach at your ear. But no summation is involved, as the soundwaves superimpose on each other.
edit: sum of vectors ...
The graph below illustrates what pico is describing.
The Linkwitz-Riley 2nd order (LR2) filter illustrates how the two -6 dB points 'sum' to flat.
The Butterworth filter gives a hump which can be minimised by moving the lowpass frequency down a bit and the highpass frequency up a bit.
The Linkwitz-Riley 2nd order (LR2) filter illustrates how the two -6 dB points 'sum' to flat.
The Butterworth filter gives a hump which can be minimised by moving the lowpass frequency down a bit and the highpass frequency up a bit.
One of the reviews for the 800 Hz Low Pass Filter essentially echos what you all informed me. I see that combining the 800Hz Low Pass filter in front of the woofer in parallel and then the aforementioned 800 Hz High pass filter in parallel just in front of the planar tweeter/mid would actually result in a slight bump at 800Hz instead of a dip in the summed frequency response.
Thanks again for the expertise and insight.
Thanks again for the expertise and insight.
Well spotted!
Yes, this is not an LR2 crossover, but the expected slight hump need give you no cause for concern as other factors are at play.
An optimum crossover would be specifically designed to match the T/S parameters of the drivers - a job for the experts.
Nevertheless, you may be pleasantly surprised by the results obtained from your store bought crossover.
Do let us know the outcome.
Yes, this is not an LR2 crossover, but the expected slight hump need give you no cause for concern as other factors are at play.
An optimum crossover would be specifically designed to match the T/S parameters of the drivers - a job for the experts.
Nevertheless, you may be pleasantly surprised by the results obtained from your store bought crossover.
Do let us know the outcome.
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This is a Klipsch KG2 crossover I am using with an Infinity QA driver and a Heil tweeter.
It sounds pretty good as is, but the Heil's need a 3-6db cut as it's more efficient than the woofer.
Stock resistor is a 3 Ohm, 1% as seen in the center here.
I have various value wire wound resistors to tinker with.
Where should I put it in this circuit to cut this tweeter level a few DB's?
Can I put another in parallel to the original like you would bypassing a capacitor to add value?
Any knowledge is appreciated
Hi yomav! Clicking on your photo simply takes me to an Audiokarma log in page.
Please cut and paste, or attach, the photo directly to this thread so we can easily study its layout.
Attenuating the tweeter may be done with a series/parallel combination of fixed resistors called an L pad.
Below is an example of an L pad placed between the treble crossover components and the tweeter.
R1 is in series with the tweeter and R2 is in parallel with it.
In order to calculate the required resistor values to suit the degree of attenuation required we need to know the nominal impedance of your tweeter.
Please cut and paste, or attach, the photo directly to this thread so we can easily study its layout.
Attenuating the tweeter may be done with a series/parallel combination of fixed resistors called an L pad.
Below is an example of an L pad placed between the treble crossover components and the tweeter.
R1 is in series with the tweeter and R2 is in parallel with it.
In order to calculate the required resistor values to suit the degree of attenuation required we need to know the nominal impedance of your tweeter.