Designing Speaker System (Advice Needed)😕
If I have a 700 Watt Stereo Power Amplifier (350 Watts Per Channel). I wish to wire a total of 8 speakers (4 Woofers each at 8 Ohms going to an inductor crossover & 4 Midrange Speakers each at 8 Ohms going through a 400 Volt Film Capacitor crossover) all together within one single speaker cabinet. How should I wire/configure this without overloading my power amplifier?
1. Woofer: Out of the four woofers (each 8 ohms) – can I safely wire each “pair” of woofers in series going to the amplifier; which will give me 4 ohms?
and in addition to the above within one single speaker cabinet; can I also wire the following:
1. Midrange: Out of the four midranges (each 8 ohms) – can I safely wire each “pair” of midranges in series going to the amplifier; also, which will give me 4 ohms? NOTE: Please keep in mind that ALL of the midrange speakers are going to 400 Volt Film Capacitor …..does this effect impedance/ohmages?
Now with everything as outlined above give me a total combined ohmage of 4 Ohms or 2 Ohms?
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My second option would be to connect all of the four 8 ohm Woofers in series together and all of the four 8 ohm Midranges together going together into one amplifier terminal which will give me a total speaker ohmage of 16 ohms?
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So what is my best solution for this speaker configuration without overloading my amplifier?
Thanks everyone for your assistance.
If I have a 700 Watt Stereo Power Amplifier (350 Watts Per Channel). I wish to wire a total of 8 speakers (4 Woofers each at 8 Ohms going to an inductor crossover & 4 Midrange Speakers each at 8 Ohms going through a 400 Volt Film Capacitor crossover) all together within one single speaker cabinet. How should I wire/configure this without overloading my power amplifier?
1. Woofer: Out of the four woofers (each 8 ohms) – can I safely wire each “pair” of woofers in series going to the amplifier; which will give me 4 ohms?
and in addition to the above within one single speaker cabinet; can I also wire the following:
1. Midrange: Out of the four midranges (each 8 ohms) – can I safely wire each “pair” of midranges in series going to the amplifier; also, which will give me 4 ohms? NOTE: Please keep in mind that ALL of the midrange speakers are going to 400 Volt Film Capacitor …..does this effect impedance/ohmages?
Now with everything as outlined above give me a total combined ohmage of 4 Ohms or 2 Ohms?
*********************
My second option would be to connect all of the four 8 ohm Woofers in series together and all of the four 8 ohm Midranges together going together into one amplifier terminal which will give me a total speaker ohmage of 16 ohms?
*************************
So what is my best solution for this speaker configuration without overloading my amplifier?
Thanks everyone for your assistance.
Hey ACVegas!
Why don't you try using a simulator like XSim? It would help you get your math right and experiment with a variety of different solutions. The default driver is an "ideal" 8 Ohms.
You can download FRD/ZMA data for Dayton drivers from Parts Express (on the product pages) so you can further refine your thinking a little with real data.
Things will change when you get woofers into cabinet, but the principles you learn will be correct.
You may also want to see my blog page on crossover impedance here.
Best,
Erik
Why don't you try using a simulator like XSim? It would help you get your math right and experiment with a variety of different solutions. The default driver is an "ideal" 8 Ohms.
You can download FRD/ZMA data for Dayton drivers from Parts Express (on the product pages) so you can further refine your thinking a little with real data.
Things will change when you get woofers into cabinet, but the principles you learn will be correct.
You may also want to see my blog page on crossover impedance here.
Best,
Erik
Your description is a little bit confusing, but I will try...
If your amplifier has 350 W per channel at 4 ohm load and if you have TOTAL of four 8-ohm woofer and four 8-ohm midranges, than you have two woofers and two midranges per amplifier channel.
Wire two woofers in parallel for 4-ohm load and add a single inductor for them, wire two midranges in parallel (for 4-ohm load) and add a single capacitor for the midranges. This is a complete loudspeaker with 4-ohm nominal impedance. Than connect this loudspeaker to the first amp channel.
Repeat the same procedure for the second pairs of woofers and midranges and connect it to the second amp channel.
You can merge two required enclosures in a single one, if necessary.
or,
If your amplifier is bridgeable, than it has 700 W at 8-ohm load, and if you have TOTAL of four 8-ohm woofers and four 8-ohm midranges, than wire four woofers in serial-parallel to get 8-ohm total load and add a single inductor, wire four midranges in serial-parallel to get 8-ohm total load and add a single capacitor. This is a complete loudspeaker with 8-ohm nominal impedance. Than connect this loudspeaker to the bridged amplifier.
If your amplifier has 350 W per channel at 4 ohm load and if you have TOTAL of four 8-ohm woofer and four 8-ohm midranges, than you have two woofers and two midranges per amplifier channel.
Wire two woofers in parallel for 4-ohm load and add a single inductor for them, wire two midranges in parallel (for 4-ohm load) and add a single capacitor for the midranges. This is a complete loudspeaker with 4-ohm nominal impedance. Than connect this loudspeaker to the first amp channel.
Repeat the same procedure for the second pairs of woofers and midranges and connect it to the second amp channel.
You can merge two required enclosures in a single one, if necessary.
or,
If your amplifier is bridgeable, than it has 700 W at 8-ohm load, and if you have TOTAL of four 8-ohm woofers and four 8-ohm midranges, than wire four woofers in serial-parallel to get 8-ohm total load and add a single inductor, wire four midranges in serial-parallel to get 8-ohm total load and add a single capacitor. This is a complete loudspeaker with 8-ohm nominal impedance. Than connect this loudspeaker to the bridged amplifier.
Loudspeaker Configurations
🙂I never heard of "Xsim". Sounds like it will help me on loudspeaker experimenting. There are quite of few Speaker Calculators out there I am aware of and have used .... but nothing like "XSim". Just viewing it quickly; it kinda reminds of "PCB Design Software" (used to design Printed Circuit Boards) which I have used before .... well in that case XSim should be easy for me to use configuring loudspeaker ohmage, capacitance, inductance, resistance, etc. Eriksquires thanks a million for the info.
🙂I never heard of "Xsim". Sounds like it will help me on loudspeaker experimenting. There are quite of few Speaker Calculators out there I am aware of and have used .... but nothing like "XSim". Just viewing it quickly; it kinda reminds of "PCB Design Software" (used to design Printed Circuit Boards) which I have used before .... well in that case XSim should be easy for me to use configuring loudspeaker ohmage, capacitance, inductance, resistance, etc. Eriksquires thanks a million for the info.
🙂I guess the way I should have worded it (simpler): I have four 8 ohm midranges and I have four 8 ohm woofers all together to fit into one single soon to be built speaker enclose. A total of 8 Loudspeaker Drivers within one single speaker enclosure. My stereo amplifier can drop down to 4 ohms per channel with no problem if I have push it to that.
1. What is the best way to wire the Four 8 ohm woofer speakers without over loading my amplifier – in series or parallel?
2. What is the best way to wire the Four 8 ohm midrange speakers without over loading my amplifier – in series or parallel?
NOTE: And later sometime this week I will be using “Xsim” that forum member “eriksquires” bought to my attention.
And thanks everyone for all of your assistance.🙂
In general, keeping all impedance above 4 Ohms is good. Going below that starts to depress the frequency response with all but the best amps. Some makers do this deliberately, by putting a 2-3 Ohm dip around 100-200 Hz they make the speakers more amp sensitive, drives audiophiles apoplectic with glee. 🙂
If you are doing 4 x 8 Ohm drivers usually this is done by arranging 2 pairs. There are two common arrangements:
Within 2 speakers in parallel so: 1 / ( (1/8) + (1/8) ) = 4 Ohms for each section.
Putting the sections them in series: 4 + 4 = 8
OR
Each section is in series: 8 + 8 = 16
But each section is in parallel to each other: 1 / ( ( 1/16) + (1/16) ) = 8
Either way it's the same. 🙂
The worst way is to wire all 4 in parallel. Then you get:
1 / ( (1/8) + (1/8) + (1/8) + (1/8) )= 2 Ohms
Best,
Erik
If you are doing 4 x 8 Ohm drivers usually this is done by arranging 2 pairs. There are two common arrangements:
Within 2 speakers in parallel so: 1 / ( (1/8) + (1/8) ) = 4 Ohms for each section.
Putting the sections them in series: 4 + 4 = 8
OR
Each section is in series: 8 + 8 = 16
But each section is in parallel to each other: 1 / ( ( 1/16) + (1/16) ) = 8
Either way it's the same. 🙂
The worst way is to wire all 4 in parallel. Then you get:
1 / ( (1/8) + (1/8) + (1/8) + (1/8) )= 2 Ohms
Best,
Erik
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Series/parallel, then wire the composite woofer to one channel and the capped off composite midrange to the other to create a 350 W mono system once you feed both channels with a full range signal. If the amp has gain controls, then you can use it to tonally balance the mids to the woofer if need be.
GM
GM
If my tweeter is 6 Ohm, the 8 Ohm midrange and the 4 ohm woofer.
Is there any way to know the final impedance (even if close) of the system without taking measurements?
Is there any way to know the final impedance (even if close) of the system without taking measurements?
Impedance varies with frequency; If you just want to be sure that you won't blow up your amp, use the Re of the lowest impedance driver
Not really! 🙂 Impedance is complicated. Vendors pick a number like 4 Ohms, but these 1 number measurements are pretty subjective. Please see my blog post which may help you understand how it all comes together:
https://speakermakersjourney.blogspot.com/2016/12/crossover-basics-impedance.html
You can however assume, more or less, if you use a well built crossover, that the minimum impedance will be the minimum (or Re) of all your drivers. For instance, if you have a tweeter with an Re of 8 and woofer with an Re of 6, you can assume 6 will be the minimum. The crossover (if well designed) should protect your amp from having to face your drivers in parallel.
Erik
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Z=sqr[(Xl-Xc)^2+R^2] Z is total impedance
Xc=1/(2pi*f*C)
Xc is capacitive reactance
f is frequency in Hz
C is capacitance in farads
Xl=2pi*f*L
Xl is inductive reactance
f is frequency
L is inductance in Henries
With the above, you can figure out the impedance response of your configuration.
The easier way is to plug all your numbers into a simulator
sent from my mobile look-at device
Xc=1/(2pi*f*C)
Xc is capacitive reactance
f is frequency in Hz
C is capacitance in farads
Xl=2pi*f*L
Xl is inductive reactance
f is frequency
L is inductance in Henries
With the above, you can figure out the impedance response of your configuration.
The easier way is to plug all your numbers into a simulator
sent from my mobile look-at device
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