Speaker Ohms

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Hi,

I'm not sure if im in the correct form but I have a few questions about wiring speakers to change the ohms. I know that 4 (8 ohms) speakers can be wired in series to give you a 8 ohms load and in parallel to give you 2 ohms.

first question
Based on the concept of wiring 4 (8ohms) speakers in series to give an 8 ohms load, can I wire 4 (8 ohms) 2 way cabinet to get an 8 ohms load?

Also, I read online that you can wire 3 (8 ohms) speakers, 2 in series and 1 in parallel to give you a 5.3 ohms load but its not recommend to do so, instead, an (8 ohms) resistor should be used to act as a dummy speaker to make up the 4th speaker.

Second question
If i were to used a resistor to act as a dummy speaker does the resistor rms watts needs to add up to one of the speaker RMS?

Regards,
 
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first question
Based on the concept of wiring 4 (8ohms) speakers in series to give an 8 ohms load, can I wire 4 (8 ohms) 2 way cabinet to get an 8 ohms load?
Yes, it doesn't matter if it's a full range, 2 way, 3 way etc.
Also, I read online that you can wire 3 (8 ohms) speakers, 2 in series and 1 in parallel to give you a 5.3 ohms load but its not recommend to do so, instead, an (8 ohms) resistor should be used to act as a dummy speaker to make up the 4th speaker.
What are you trying to accomplish? More info please.
Second question
If i were to used a resistor to act as a dummy speaker does the resistor rms watts needs to add up to one of the speaker RMS?
Regards,
Yes but why?
 
Yes, it doesn't matter if it's a full range, 2 way, 3 way etc.

What are you trying to accomplish? More info please.

Yes but why?

Thank you for the quick response Cal.

ok, so I have 6 (8") woofer and and 2 (1") exit horn and i was planning to build 2 full range cabinet, 3 woofer and 1 horn as a fun & cheap project. But, instead in building a custom crossover I wanted to add the resistor to make up for the 4th speaker so that I can use a standard 8 ohms 2 way crossover.
 
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Joined 2004
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Using a resistor is a waste of power and it will have to be large. Consider this: Use one woofer and one tweeter in a set of cabinets. Those we'll call those the satellites.

Make another cabinet with 4 woofers for a bass unit. Use a plate amp to run the woofer box.
or
Make two cabinets with two woofers each. This would require two plate amps, one per box.
 
A "fun & cheap project"doesn't need such attention to details.
Use a 4.7uF capacitor in series with your tweeter and you're good to go!
But if you wanna go specific on that stuff, do the following:
1- Measure the drivers. You'll find several methods for that. Here's one:
Measuring Loudspeaker Driver Parameters
2- Design the Speaker box. Here's WinISD one of the best and free speaker designing programs.
LinearTeam
3- Design the Crossovers. There are several free crossover calculators on the net. winISD has some good calculator too.
 
A "fun & cheap project"doesn't need such attention to details.
Use a 4.7uF capacitor in series with your tweeter and you're good to go!
But if you wanna go specific on that stuff, do the following:
1- Measure the drivers. You'll find several methods for that. Here's one:
Measuring Loudspeaker Driver Parameters
2- Design the Speaker box. Here's WinISD one of the best and free speaker designing programs.
LinearTeam
3- Design the Crossovers. There are several free crossover calculators on the net. winISD has some good calculator too.

Thanks for the info
 
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