Dear All,
I have the following pairs of drivers:
1. 12" Full range -100W RMS, 8Ohms, 97dB sensitive.
2. 10" Bass driver - 200W RMS, 4Ohms, 89dB sensitive.
12" FR is in a sealed box, 10" bass driver is in a ported box.
I have a 4ohms stable stereo amp.
Is it possible to use a simple capacitor as a crossover?
My requirement is not a properly designed crossover with all the peaks and dips tamed and get a flat response.
I just need to split the signal around 120 to 150hZ
Is it possible this way? What capacitor may work?
Most importantly...Is there a risk of blowing my drivers or amp?
I can give full specs of drivers if needed.
Thanks in advance for any suggestions ...
I have the following pairs of drivers:
1. 12" Full range -100W RMS, 8Ohms, 97dB sensitive.
2. 10" Bass driver - 200W RMS, 4Ohms, 89dB sensitive.
12" FR is in a sealed box, 10" bass driver is in a ported box.
I have a 4ohms stable stereo amp.
Is it possible to use a simple capacitor as a crossover?
My requirement is not a properly designed crossover with all the peaks and dips tamed and get a flat response.
I just need to split the signal around 120 to 150hZ
Is it possible this way? What capacitor may work?
Most importantly...Is there a risk of blowing my drivers or amp?
I can give full specs of drivers if needed.
Thanks in advance for any suggestions ...
Why you need a crossover for the full range? Why you need a separate bass driver? The full range has no bass in a sealed box? Than try the full range in a ported box - maybe you don't need a bass driver at all.
Your full range is way more sensitive than the bass driver. You need a bass driver with the same sensitivity as the full range. And you need a proper crossover - at least an inductor for bass driver and a capacitor for the full range.
Your full range is way more sensitive than the bass driver. You need a bass driver with the same sensitivity as the full range. And you need a proper crossover - at least an inductor for bass driver and a capacitor for the full range.
be aware that passive odd order highpass filters will interact with the speaker's impedance, and often push the speaker lower and excursion higher than the target if the load were a resistor
look at Fane's 12-TC250 in a 35 liter closed box using 80uF cap
a properly chosen LCR network across your 12" driver could flatten impedance so a cap may work - there may be other ways
including swamping resistors and aperiodic enclosures
look at Fane's 12-TC250 in a 35 liter closed box using 80uF cap
a properly chosen LCR network across your 12" driver could flatten impedance so a cap may work - there may be other ways
including swamping resistors and aperiodic enclosures
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Hey Sonce... thanks for the inputs. My FR rolls off at 100hz even in a ported box. And for its Vas and Qts, it needs really a huge box !!
be aware that passive odd order highpass filters will interact with the speaker's impedance, and often push the speaker lower and excursion higher than the target if the load were a resistor
look at Fane's 12-TC250 in a 35 liter closed box using 80uF cap
a properly chosen LCR network across your 12" driver could flatten impedance so a cap may work - there may be other ways
including swamping resistors and aperiodic enclosures
Hi Freddi, thank you for the inputs... I will try to explore and study further.
someone here at the multi-way forum should be able to come up with a good solution - I have very little skill with crossovers.
FWIW - here's a simulation of your 12" in a 35 liter sealed box with 80uF capacitor vs the same but with an impedance notch filter. I came up with a 7mH inductor with 1 ohm DCR in series with 400uF electrolytic non-polar to flatten the impedance peak and that peak's effect upon response and excursion.
The fullrange forum should be useful too as they often deal with "FAST" or what I think P10 calls "WAW" (Woofer Assisted Wideband - IIRC) - maybe there's a way to reduce the system resonance peak with some sort of aperiodic vent.
Hopefully someone with better skills than myself will chime in.
FWIW - here's a simulation of your 12" in a 35 liter sealed box with 80uF capacitor vs the same but with an impedance notch filter. I came up with a 7mH inductor with 1 ohm DCR in series with 400uF electrolytic non-polar to flatten the impedance peak and that peak's effect upon response and excursion.
The fullrange forum should be useful too as they often deal with "FAST" or what I think P10 calls "WAW" (Woofer Assisted Wideband - IIRC) - maybe there's a way to reduce the system resonance peak with some sort of aperiodic vent.
Hopefully someone with better skills than myself will chime in.
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The simplest solution: get 12" or 15" bass driver with 97 dB sensitivity and 8-ohms nominal impedance, build some good bandpass enclosure for it and connect it parallel to the fullrange driver (in a 28 L sealed box). You don't need a capacitor at all, if you are not looking for a maximum possible power handling.
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ooh ... that's interesting to know .... So you are suggesting, if the sensitivity and impedance is same for two drivers, they can be connected in parallel !! (hope my understanding is correct)
I am curious to know, the entire full range signal will be fed into both the drivers.
So basically the mids and highs will also go to the bass driver, and the lows will also go to the full range. How do they operate? Does it cause any problems?
I am curious to know, the entire full range signal will be fed into both the drivers.
So basically the mids and highs will also go to the bass driver, and the lows will also go to the full range. How do they operate? Does it cause any problems?
28 liter was a good choice and typical for a 12" to be used that way.
fwiw I've not looked at your woofer in depth but a series vented bandpass box I had with an 88dB 10 worked pretty well with 35 liters per chamber and gave -3dB @ 28Hz/110Hz. Maybe your woofer would be similar but shifted up a bit. (so far - not got acceptable results - WinISD might be helpful)
12" FR - 28 liter at nominal 1 and 100 watts input
fwiw I've not looked at your woofer in depth but a series vented bandpass box I had with an 88dB 10 worked pretty well with 35 liters per chamber and gave -3dB @ 28Hz/110Hz. Maybe your woofer would be similar but shifted up a bit. (so far - not got acceptable results - WinISD might be helpful)
12" FR - 28 liter at nominal 1 and 100 watts input
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No problems, two 8-ohm speakers in parallel make total impedance of 4 ohms, which will be handled by any decent amplifier.
Ideal band-pass bass enclosure emits only low frequencies (in spite of feeding it with full-range frequency spectrum). Closed box naturally limits low frequency excursion of the 12" full-range driver.
This will work, but you need a bass driver with at least 95 dB sensitivity.
fwiw I think the FR12 would be better off with a 2nd order highpass vs cap + impedance notch filter
in the US, this Dayton 4mH coil (0.44 ohm dcr) would work Dayton Audio 4.0mH 18 AWG I Core Inductor Crossover Coil
in the US, this Dayton 4mH coil (0.44 ohm dcr) would work Dayton Audio 4.0mH 18 AWG I Core Inductor Crossover Coil
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Hi Aud,
as others have pointed out, the answer is no, it will not work with a single capacitor. Your choice of 12-inch-fullrange with 10-inch woofer is also doubtsome, it will not work correctly, the FR will be a lot louder. You will need at least a 15-inch bass driver, all else is probably not worth the effort.
And there´s more to a good crossover... calculations and simulation are fine, but a good passive FAST crossover is a lot of work, I´ve been doing this for several combinations in the last few years.
Your FR data don´t look too well either, sorry. I would, from TSP alone, suggest to try a large closed or aperiodic enclosure, or maybe a TML? Whatever you do, this driver all alone might be your most effective approach for small money and efforts, but without correction filter (which requires actual measurements) it will be bass shy as well, if you don´t put it straight into the corners of your room.
Sorry again, no intention to desencourage you, but I fear that´s how it is.
All the best
Mattes
as others have pointed out, the answer is no, it will not work with a single capacitor. Your choice of 12-inch-fullrange with 10-inch woofer is also doubtsome, it will not work correctly, the FR will be a lot louder. You will need at least a 15-inch bass driver, all else is probably not worth the effort.
And there´s more to a good crossover... calculations and simulation are fine, but a good passive FAST crossover is a lot of work, I´ve been doing this for several combinations in the last few years.
Your FR data don´t look too well either, sorry. I would, from TSP alone, suggest to try a large closed or aperiodic enclosure, or maybe a TML? Whatever you do, this driver all alone might be your most effective approach for small money and efforts, but without correction filter (which requires actual measurements) it will be bass shy as well, if you don´t put it straight into the corners of your room.
Sorry again, no intention to desencourage you, but I fear that´s how it is.
All the best
Mattes
Dear Mattes, I completely understand your intention is not to discourage.
Your are just revealing the facts, and that truly what we all need.
After all, this is physics
This FR is a pro driver, and as you pointed out, it goes pretty loud indeed.
And to get a good low end, it needs a "huge" enclosure.
So I thought to keep the sealed enclosure small enough to go down to 100hZ, and use a separate bass driver for low end. Any how I just thought of giving a try if it can be done with minimal efforts.
But it looks like there is a lot more to do than a simple capacitor. I understand. Thanks a lot !!
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