If I want to stick a simple passive high pass filter onto a tweeter (and nothing else), how do I calculate what micro-farad (uF) and volage I need for any given frequency?
*** more complex crossover calculations/guides are easy to find, but too advanced for my needs.
*** more complex crossover calculations/guides are easy to find, but too advanced for my needs.
Here you have a table with the values corresponding to the simplest of filters, only C.
If it's unpolarized it will go either way, if it's polarized the positive side of electrolytic C goes to the positive side of the tweeter.
http://audiocarpy.blogspot.com/2014/01/capacitores-para-drivers-y-tweeters.html
If it's unpolarized it will go either way, if it's polarized the positive side of electrolytic C goes to the positive side of the tweeter.
http://audiocarpy.blogspot.com/2014/01/capacitores-para-drivers-y-tweeters.html
There's a misunderstanding about the capacitor polarity. All that is required is to connect two equal
polarized capacitors in anti-series, to form an unpolarized capacitor.
It does not matter where in the circuit branch the capacitors are connected. The tweeter could be on either side
of the series capacitors, or in between them. It would all work exactly the same.
The tweeter + marking means that when a positive voltage is applied to that terminal relative to the unmarked terminal,
the cone will move forward.
polarized capacitors in anti-series, to form an unpolarized capacitor.
It does not matter where in the circuit branch the capacitors are connected. The tweeter could be on either side
of the series capacitors, or in between them. It would all work exactly the same.
The tweeter + marking means that when a positive voltage is applied to that terminal relative to the unmarked terminal,
the cone will move forward.
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That's a handy table which avoids any need for calculation in most applicable situations.
I do think, however, that we should stress that only non-polarised (NP) capacitors should be used in loudspeaker crossovers.
New member, wickette, appears not to be looking for an LC filter calculator - he refers to a single capacitor high pass filter.
So, this is the one I would choose from your search list:
https://www.claredot.net/en/sec-Sound/high-pass-cross-over-6dB.php
@ wickette: You asked about voltage. If it's a domestic speaker, choose a minimum rating of 70 V DC - and it's perfectly OK to go higher.
)Thank you! My powerful amp is using a 30V DC PSU 140watt RMS out, 100V cap is enough?
Ample, but remember it still must be a bipolar/non polar/film cap, NOT a regular/polarized electrolytic.
So, obviously I'm a super newb, and Im playing with cheap 2,3,4 way coaxial speakers. My assumption was the woofer was 8ohm, and whatever was in the center housing was 8ohms since all of these speakers just have a single capacitor. But I don't think this was a correct assumption. Would I have anyway of knowing the tweeter impedance without breaking anything?
I wanted cancel out the brightness by changing the capacitors so the cut off is over 8k-10k on the tweetiest speakers. ...And if that did't work stick a resistor next to the capacitor to hush them up... all bad ideas right?
I wanted cancel out the brightness by changing the capacitors so the cut off is over 8k-10k on the tweetiest speakers. ...And if that did't work stick a resistor next to the capacitor to hush them up... all bad ideas right?
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Just try a capacitor of half the capacitance value of the one currently fitted.
As Nigel said earlier, 2.2 uF is a good bet. It filters an 8 ohm tweeter at 9,000 Hz.
As Nigel said earlier, 2.2 uF is a good bet. It filters an 8 ohm tweeter at 9,000 Hz.
You can wire a resistor in series with the capacitor if the tweeter is too loud - a 2.2 ohm; 5 or 10W ceramic resistor would be a reasonable value to try.
If they are car speakers, they are likely to be 4 ohm.
If that is the case, then it would be best just to half the value of the currently fitted capacitor.
Wow, the bold highlighted part is wrong, yet another proof that the internet is full of crap.
It is a first order filter ( 6 dB/octave.)
http://audiocarpy.blogspot.com/2014/01/capacitores-para-drivers-y-tweeters.html
But the table attached to that link is OK, the OP can check it with this online calculator.
https://www.pcpaudio.com/pcpfiles/doc_altavoces/filtros_pasivos/filtrospasivos.php#filtro2
Sorry for the mistake. The intention was to help and I did not pay too much attention to what I copied
" Some important information and tips before installing the capacitor:
1· The capacitors have to be installed on the positive lead of the audio component.
2- There are polarized and depolarized capacitors.
The polarized ones: they have to be connected in series with the cable, that is, the negative part (shorter leg and a mark with a white stripe) has to be connected in the direction of the cable that goes to the amplifier and the positive part has to be connected towards the positive pole of the speaker, driver or super tweeter (the positive pole has the longest leg)
The depolarized: they can be connected in any way because they do not have polarity. "
However, you have repeated it by emphasising in bold the false "Some important information and tips before installing the capacitor".
That was best left unquoted.
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I'll make an appointment with a text comprehension specialist then, thanks for caring about my mental capabilities.