Ohm calculation
- Thread starter prodjay
- Start date
Yes ... (R1 x R2) / (R1 + R2) .. so for 1 and 2, that's 8x8/8+8 = 4 .. then the 3rd .. 4x8/4+8 = 2.667.
Formally, it's:
Formally, it's:
While Steve's formula is correct, the long version is only necessary when connecting multiple speakers of different impedance. If they are all 8ohm it's simply 8/3 = 2.67
Regardless of the fact that most modern solid state amplifiers are rated for 2 ohm loads (unbridged), It's still not a good idea to run more than two per channel (a 4 ohm load) for any length of time as it's hard on both the amp and the voice coils in the speakers.
That's why you will usually see a minimum impedance spec listed for passive speakers.
If you want to run more than 2 per channel in parallel, you should really be using 16 ohm speakers imo.
Regardless of the fact that most modern solid state amplifiers are rated for 2 ohm loads (unbridged), It's still not a good idea to run more than two per channel (a 4 ohm load) for any length of time as it's hard on both the amp and the voice coils in the speakers.
That's why you will usually see a minimum impedance spec listed for passive speakers.
If you want to run more than 2 per channel in parallel, you should really be using 16 ohm speakers imo.
Speakers are not pure resistance. They have impedance, which is a complex load, and varies with frequency - it's even worse if a passive crossover is involved. An "8 ohm" speaker will often measure lower at some frequency - as DJ TJ says, do your amp a favor and don't run lower than 4 ohms.
D
Depends on how the three 8 ohm speakers are wired together. If you put the drivers in series you get a 24 ohm load.
Depends on how the three 8 ohm speakers are wired together. If you put the drivers in series you get a 24 ohm load.
Heh, that's true he didn't specify.
Good observation!
I'll blame Steve, I was just copying him.....I just stated the short version.
I guess we were all just confirming he had the calculation right and that he knew what he was doing, hehe.
Good observation!
I'll blame Steve, I was just copying him.....I just stated the short version.
I guess we were all just confirming he had the calculation right and that he knew what he was doing, hehe.
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This would be 3 ea. subwoofers that are 8 ohm each.
After all the advice, I will just run 2 subs on another amp.