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Joe Bonamassa Forum → Joe's Guitars, Amps and Gear → Is this series or parallel?
Is this cab wired in series or parallel? I am going with series. Does anyone else agree?
http://picasaweb.google.com/giodasilva/ … 4563514610
looks like series to me
Series, Think of it as wiring two amps together. The first speaker gets the signal from the speaker lead and sends it to the second speaker..Parallel would be two leads from the speaker jack..
joe b
Oh yeah its Series. I work with an Electrical Engineer and he said Series when he looked at it.
Parallel is positive to positive whether it is jumpered like in the photo or two leads. Series is when the jumper would be positive to negative on the second speaker. Basically reversing the polarity of the second speaker. If the two are wired Parallel then the impedance would drop in series it would increase. Hard to tell in the photo if the jumper cable is from positive to positive and negative to negative.
Thanks everyone! I will have to check the polarity bit since that did not occur to me.
The speakers are wired in parallel. The right speaker's voice coil is fed off of the left speaker's. If it was series, there would only be one wire between the two speakers instead of two, and the heavy red wire would go to one speaker and the heavy white wire to the other. Additionally, I've never seen a twin speaker combo wired in series. Not that people don't do it; it's just very uncommon.
Although the speakers are wired in parallel, it appears that the polarity is wrong on one of them. The white interconnect wire connects both of the top speaker terminals. If the top connector (heavy red wire) of the left speaker is positive, by all rights the positive terminal on the right speaker should be on the bottom since the speaker is rotated 180 degrees.
If the speakers are wired out of phase as I suspect, you'll get a much better tone by correcting the phasing (matching pos. to pos. and neg. to neg.). Hope that helps.
Yeah, I did some looking around in the Carvin website, seems they wire their speakers in parallel that way in their 2x12's. I will check the polarity to make sure it is correct tomorrow. Thanks guys, major help!
YEP it is definately parrallel which means that the impedance of both speakers is added together then divided by no of speakers ie 8+8ohm divided by 2 =4ohms if it was wired in series the you would add the impedance of both speakers together ie 8+8 =16 ohms
YEP it is definately parrallel which means that the impedance of both speakers is added together then divided by no of speakers ie 8+8ohm divided by 2 =4ohms if it was wired in series the you would add the impedance of both speakers together ie 8+8 =16 ohms
Not wanting to be the Math police but somethings wrong. If it's ohms + ohms/# of speakers, then 8+8 =16, 16/2=8ohms. Is that the right formula?
I don't know the math formula but two 8 ohm speakers wired in parallel = a 4 ohm load. The main reason to use a series parallel wiring harness is when you have four 8 ohm speakers that you want to wire together and not end up with a 2 ohm load.
2 pairs of 8 ohm speakers wired in series then wired in parallel to achieve an 8 ohm load. Here is a link to a diagram just scroll down the page a bit http://webervst.com/sptalk.html
SOFTMC wrote:YEP it is definately parrallel which means that the impedance of both speakers is added together then divided by no of speakers ie 8+8ohm divided by 2 =4ohms if it was wired in series the you would add the impedance of both speakers together ie 8+8 =16 ohms
Not wanting to be the Math police but somethings wrong. If it's ohms + ohms/# of speakers, then 8+8 =16, 16/2=8ohms. Is that the right formula?
No, the formula is 1/RT=1/R1+1/R2+1/R3...
If speakers of equal value are in parallel, you may simplify by dividing the resistance of 1 by the number, thus 8/2=4, 8/3=2.67 and so forth. In a cab with 4 speakers, if there is only a choice of a mono output of 4 or 8 Ohms, it is best for the amp to wire them in series-parallel so the combined impedance to the amp is 8 Ohms, thus avoiding a power mismatch. It is always better to mismatch high than low to avoid overloading the output transformer. Simply stated, current through the transformer windings is found by Ohm's law, I(current)= E(voltage)/R(resistance) Since Voltage is constant in the amp output at any given gain setting, the current is inversely proportional to the resistance of the load. As the load resistance decreases, the current through the transformer windings increases.
Speakers in series are all additive. Rt=R1+R2+R3...
The pictured speakers are in parallel.
Polarity can be checked by use of a 9V battery. Use clip leads and momentarily touch the leads to the speaker connections observing which was connected to the positive pole of the battery. The speaker will either pull in or push out. Connect the amp to the speakers so they all move in the same direction.
I hope that clarifies the matter for you guys.
For a complete discussion of the matter, refer to this tutorial. http://www.electronics-tutorials.ws/resistor/res_4.html
Just to add to Rickb's post, if you don't have a calc. to find the inverse of the resistor values, another formula for figuring parallel resistance is (R1xR2)/(R1+R2). Sorry, division is still required. 
SOFTMC wrote:YEP it is definately parrallel which means that the impedance of both speakers is added together then divided by no of speakers ie 8+8ohm divided by 2 =4ohms if it was wired in series the you would add the impedance of both speakers together ie 8+8 =16 ohms
Not wanting to be the Math police but somethings wrong. If it's ohms + ohms/# of speakers, then 8+8 =16, 16/2=8ohms. Is that the right formula?
Sorry my bad Math right answer wrong formula 
here is a very usful link that takes the headache away when wiring speakers it is Invaluable !!!
http://www.duncanamps.com/technical/impedance.html
Everyone seems to have better eyes than me. I cannot tell what it is. It looks to be series to me first glance. However, I cannot tell where those wires are going! Another minute it looks parallel!!!!!!!
From the crimped lug of the left speaker's RED wire, does it connect to the bottom terminal of the right speaker???? If yes, that is parallel. That is assuming the BLACK wire between the lugs is going from the left speaker bottom terminal to the right speaker top terminal, further assuming those are exactly identical speakers with matching terminal polarity (appears to be so). If not....if that BLACK wire jumpers the top left to the top right, that is series...
Tell me where the wires go and I could be sure.
Also, those formulae are for resistors and static resistance, i.e. no input signals ONLY. Mutual inductance and frequency dependent signals can determine the actual resultant impedance(s) at any given moment. The stated impedance is useful however, as for general considerations only such as amplifier(s) to load(s)!!! I have to wonder about all those blown amps and gear during Joe Bonamassa / Beth Hart sessions......
Rock ON & Keep the Faith,
Rocket
"Alright, got the cab reloaded with some Hellatone 30's and though the Carvin speakers were great for what they are, I do prefer the celestion G12H30 types of tone. Luckily my amp is only pushing about 50 watts, and I don't need the mammoth power handling like say, someone with a JB type of rig needs, so no need for EV's! Thans everyone for the help in solving the series/parallel question and resolving the polarity issue. keep rocking!
Alright, got the cab reloaded with some Hellatone 30's and though the Carvin speakers were great for what they are, I do prefer the celestion G12H30 types of tone. Luckily my amp is only pushing about 50 watts, and I don't need the mammoth power handling like say, someone with a JB type of rig needs, so no need for EV's! Thans everyone for the help in solving the series/parallel question and resolving the polarity issue. keep rocking!
So what was the final verdict, parallel or series?
I need clarification to clarify the specifications of my optometry prescription...
Rock ON & Keep the Faith,
Rocket
"Oh it was parallel.
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