I have a speaker cabinet with a built in crossover (3 way....i think).
The tweeter and midrange are intact, however the 10" speaker handling the lows needs to be replaced. Ideally this would be a 4 ohm driver. I understand the relationship between amp and speakers as far as resistance goes. I'm not familiar with crossovers that much (just know what they do and a SLIGHT idea of how they do it). If I ran a higher impedance driver (8 ohm) for the 10" speaker would I be taxing the crossover in any way?
The tweeter and midrange are intact, however the 10" speaker handling the lows needs to be replaced. Ideally this would be a 4 ohm driver. I understand the relationship between amp and speakers as far as resistance goes. I'm not familiar with crossovers that much (just know what they do and a SLIGHT idea of how they do it). If I ran a higher impedance driver (8 ohm) for the 10" speaker would I be taxing the crossover in any way?
The XO frequency is dependant in part on the impedance. If you change the impedance you will change what happens at the XO point. ie: overlap or gap in the response.
overlap or gap
Overlap I could live with.....a gap in the frequency range would be a little annoying. To be specific (and beating a dead equine) it's the pair of M3's that I have and trying to get up and running. 🙄 I'm thinking of grabbing a pair of 10" mirage woofers (8 ohm) and throwing them in just to get the things running again. Before I do though I just want to make sure I don't screw things up with the xover. Being that they're not a $100 pair of speakers would there be something else other than gap and overlap that I might be doing to the xover?
Overlap I could live with.....a gap in the frequency range would be a little annoying. To be specific (and beating a dead equine) it's the pair of M3's that I have and trying to get up and running. 🙄 I'm thinking of grabbing a pair of 10" mirage woofers (8 ohm) and throwing them in just to get the things running again. Before I do though I just want to make sure I don't screw things up with the xover. Being that they're not a $100 pair of speakers would there be something else other than gap and overlap that I might be doing to the xover?
The woofer crossover components (if there are any) consist of a coil and a capacitor. If the capacitor did not blow, or coil burn along with the woofers, it is unlikely they will regardless of the new woofer's impedance.
A gap in response generally is not as annoying as a honking midrange overlap.
As well as tonal change from using a different driver than the original design called for, an 8 ohm speaker may have 3 dB less output than a 4 ohm, so the speaker may sound "thin".
If you want the speakers to sound like they did before, buy replacements with the same specifications as the original drivers.
If you don't care about the sound, go ahead and fill the speaker holes with anything 😀.
Excuse me, but the first and most obvious question is -
Ideally this would be a 4 ohm driver.
WHY?
The implication is that the existing speaker has a 4 ohms driver, but you don't actually say that. We can only know what you tell us, for us or you to proceed based on assumptions guarantees a wrong result.
So, why is the 10" driver ideally a 4 ohm? And how do you know?
The components of a crossover are driver specific. The crossover is not 1000hz no matter what driver is attached. The Driver impedance plus the desired crossover, determine the specific components in the crossover.
So, I think many more details are necessary for anyone to make any judgements or recommendations. First a complete detailed description of the project or the existing speakers - driver size, driver quantities, existing crossover frequencies if know, the cabinet size, and what ever else you can think of. Photos are always helpful.
Using a basic generic on-line crossover calculator, if we assume a 1000hz crossover (just for illustration) and a 4 ohm woofer changed to an 8 ohms woofer, here is how much the crossover shifts by changing the driver to 8 ohms. I'll assume 6db 1st order crossovers -
Crossover Design Chart and Inductance vs. Frequency Calculator(Low-pass)
This requires a 0.637 mH coil, now we change 4 ohms to 8 ohms and keep changing the frequency until we come up with the exact same coil. To get that same coil value with a 8 ohms speakers, the crossover is 2000hz. That is how far the crossover will shift if you change from 4 ohm to 8 ohm.
For the same crossover frequency the coil would have to be 1.274 mH. That is, an 8 ohms speaker crossing over at the same 1000hz.
If you currently have a 4 ohm bass driver and if you know the current crossover frequency or if you know the value of the components in the woofer crossover, then we can figure out what values you would need to change to to get the same crossover.
Again -
1.) a complete detailed description of the existing speaker or project with every detail no matter how minute. Hopefully with a photo.
2.) Values of the existing crossovers, either component values or the values of the actual crossover frequencies or both.
3.) Is this a home-made speaker or is the a commercial speaker that you are trying to repair?
Knowledge is power ...the more you have ...the more you have.
Just one man's opinion.
Steve/bluewizard
Ideally this would be a 4 ohm driver.
WHY?
The implication is that the existing speaker has a 4 ohms driver, but you don't actually say that. We can only know what you tell us, for us or you to proceed based on assumptions guarantees a wrong result.
So, why is the 10" driver ideally a 4 ohm? And how do you know?
The components of a crossover are driver specific. The crossover is not 1000hz no matter what driver is attached. The Driver impedance plus the desired crossover, determine the specific components in the crossover.
So, I think many more details are necessary for anyone to make any judgements or recommendations. First a complete detailed description of the project or the existing speakers - driver size, driver quantities, existing crossover frequencies if know, the cabinet size, and what ever else you can think of. Photos are always helpful.
Using a basic generic on-line crossover calculator, if we assume a 1000hz crossover (just for illustration) and a 4 ohm woofer changed to an 8 ohms woofer, here is how much the crossover shifts by changing the driver to 8 ohms. I'll assume 6db 1st order crossovers -
Crossover Design Chart and Inductance vs. Frequency Calculator(Low-pass)
This requires a 0.637 mH coil, now we change 4 ohms to 8 ohms and keep changing the frequency until we come up with the exact same coil. To get that same coil value with a 8 ohms speakers, the crossover is 2000hz. That is how far the crossover will shift if you change from 4 ohm to 8 ohm.
For the same crossover frequency the coil would have to be 1.274 mH. That is, an 8 ohms speaker crossing over at the same 1000hz.
If you currently have a 4 ohm bass driver and if you know the current crossover frequency or if you know the value of the components in the woofer crossover, then we can figure out what values you would need to change to to get the same crossover.
Again -
1.) a complete detailed description of the existing speaker or project with every detail no matter how minute. Hopefully with a photo.
2.) Values of the existing crossovers, either component values or the values of the actual crossover frequencies or both.
3.) Is this a home-made speaker or is the a commercial speaker that you are trying to repair?
Knowledge is power ...the more you have ...the more you have.
Just one man's opinion.
Steve/bluewizard
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