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Topic: Speaker Impedence Question |
Mark Vinbury
From: N. Kingstown, Rhode Island, USA
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Posted 2 Nov 2006 12:39 pm
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No doubt this has been covered in some other thread but I can't find it.
My Crate tube amp wants to see an 8 ohm load at the output transformer.
There is no jack for an extension speaker and the manual says to use an 8 ohm speaker.
Is there any way to wire two 8 ohm speakers to producce the 8 ohm load. I seem to remember some type of series/parallel combination in an amp I had in the past.
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Roger Kelly
From: Bristol,Tennessee
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Posted 2 Nov 2006 1:18 pm
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You could wire 2-4 ohm speakers in SERIES to get an 8 ohm load...if you want the extra speaker...otherwise just use a single 8 ohm speaker. |
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Mike Fried
From: Nashville, TN, USA
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Posted 2 Nov 2006 5:15 pm
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Alternately, you could wire two 16-ohm speakers in parallel (a more common configuration). Four 8-ohm speakers can be wired series/parallel for 8 ohms, but not two of them. [This message was edited by Mike Fried on 02 November 2006 at 05:16 PM.] |
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Jim Palenscar
From: Oceanside, Calif, USA
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Posted 2 Nov 2006 6:32 pm
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Impedence for series is an easy one- add up the total impedance of the speakers in the loop and that is what the amp is seeing. For parallel it is slightly tougher- Total impedence= a x b/a + b where a and b represent each speaker impedance. A good discussion about all this is here including how to wire them up, etc. [This message was edited by Jim Palenscar on 02 November 2006 at 06:34 PM.] |
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Gareth Carthew
From: West Sussex, UK
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Posted 3 Nov 2006 6:00 am
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Alternatively, an easier way to calculate Parallel Impedance/Resistance (and the way to calculate if you have more than two loads):
1/Rt = 1/R1 + 1/R2 + 1/R3 ...
Where
Rt is Total Resistance/Impedance
R1, R2 etc are the individual resistances/impeadances
[This message was edited by Gareth Carthew on 03 November 2006 at 06:03 AM.] |
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Jim Sliff
From: Lawndale California, USA
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Posted 3 Nov 2006 8:40 pm
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"Is there any way to wire two 8 ohm speakers to producce the 8 ohm load. I seem to remember some type of series/parallel combination in an amp I had in the past."
Simple answer - no.
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Lefty
From: Grayson, Ga.
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Posted 10 Nov 2006 2:48 am
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I have a Musicman HD130 4-10 speaker that I bought recently that is fitted with a 15" speaker (8ohm). If I want to return it to its 4-10 original config. and wire (4)8 ohm speakers for 8 ohms (lets say they are 40 watt speakers) what is the load on each speaker in wattage?
Sorry, don't mean to hi-jack this post, just dumb and curious.
Lefty[This message was edited by Lefty on 10 November 2006 at 02:49 AM.] |
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Donny Hinson
From: Glen Burnie, Md. U.S.A.
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Posted 10 Nov 2006 4:24 am
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Lefty, wire a pair of speakers in parallel (for 4-ohms), and then wire the other pair of speakers in parallel the same way (for another 4-ohms), and then wire the two 4-ohm pairs of speakers in series (4+4= .
Whatever load you're pushing will be divided equally among the 4 speakers. If your amp puts out 130 watts, each speaker would be seeing 32.5 watts at maximum output.[This message was edited by Donny Hinson on 12 November 2006 at 06:38 AM.] |
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Lefty
From: Grayson, Ga.
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Posted 10 Nov 2006 6:44 pm
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Thanks Donny.
regards,
Lefty |
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