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msrance
03-13-2004, 03:21 AM
Hello Friends, I got this new idea when I was replying to a post in this very forum.Let me explain this to you.

When you wire the speakers in series, you connect the + terminal of one speaker to the - terminal of the next speaker. The elctricity flows through one speaker, and then on to the speaker.This increases the total resistance, reducing the total acoustical ouput. That is, because the electricity has to flow through each speaker one at a time, each speaker adds it's resistance to the whole. The formula is as follows:

Speaker 1 + Speaker 2 = Total Ohms Rating
8 Ohms + 8 Ohms = 16 Ohms


when you wire the speakers in parallel it reduces the total resistance increasing the total output. That is, because electricity flows through all of the speakers simultaneously, each speaker added reduces the resistance of the chain. If you visualize all of the negative electrons on one side trying to get to the other, they'll have an easier time because there are so many possible paths for them to go by.

Resistance = 1 / (1/speaker 1 + 1/speaker 2)
Resistance = 1 / (1 / 8 Ohms + 1 / 8 Ohms)
Resistance = 1 / (2/8)
Resistance = 1 / .25
Resistance = 4 Ohms


Now comes my querry :

1. The A and B speaker connections in an Amp are series or parallel conection?

2. What if I was to connect the 2 speakers in the A pair in series and the speakers in B pair also in series and put the two pairs in parallel?

3. You know some thing that brings the final value closer to 8 Ohms - compared to my present value of closer to 2.


Now let me tell you why this whole train of thought. I have a 100 W/C yamaha Amp @ 8 Ohms (capable of supposedly handling 4 and 2 ohms).
My A pair of speakers : I connect both pairs(L + R) of positive and negative terminals to the active subwoofer 100W @ 4ohm from where one connection goes to each of the pair (L + R) of 80 W @ 4 ohms speakers.
My B pair of speakers: each of the terminals goes to its respective 120 W @ 8 ohms speakers.

I believe at present this combines to give an impedence of 2.67 ohms approx. If I could rewire the whole bunch to get it as close to 8 ohms as possible. Thanks for the help in advance. I am also cross posting this in the DIY and tweaks section of the forum.

F1
03-13-2004, 04:59 AM
Hi Msrance,
The problem hasn't solved eh?
When you drive Speaker A and B together, both speakers are in Parallel. Subwoofer will not change the total impedance so don't worry. Subwoofer will draw very little current from your amplifier. I assume you make subwoofer connection from amplifier speaker output. Connect your first front speaker from subwoofer output and then connect your second front speaker in SERIES with your first front speaker. Don't worry to get nominal impedance of more than 8 ohms. Do this and tell us what happen. Good luck.

msrance
03-13-2004, 02:06 PM
Hi Msrance, The problem hasn't solved eh?

You bet. The last one's gone where the amp used to heat and shut down - but now it sounds harsher than before and someone in the forum suggested it could be because of the low impredence that all 5 speakers put together were offering (apart from the suggestion that i was going deaf). Hence this new train of thought about how to increase the final impdence of the bunch by some permutation or combination!


When you drive Speaker A and B together, both speakers are in Parallel. Subwoofer will not change the total impedance so don't worry. Subwoofer will draw very little current from your amplifier. I assume you make subwoofer connection from amplifier speaker output.

Thats right. The subwoofer is connected from both (L + R) speaker connections of the A speaker pair. Alright so we assume its contribution as negligible and start our assumptions here onwards.


Connect your first front speaker from subwoofer output and then connect your second front speaker in SERIES with your first front speaker. Don't worry to get nominal impedance of more than 8 ohms. Do this and tell us what happen. Good luck.

Again, a new problem. Would Series mean that I connect both the + and - terminals of R speaker to the + and - of the L speaker? and then wouldn't both the speakers give the same output - and the purpose of stereo would be defeated - there would not be two channels being played - but the same channel being playd by both the speakers!

Though, I could connect both pair of speakers in this same fashion and end up with a pair each of each channel! But do reflect a bit more on the actual series connection. If only 1 of the speakers were to be connected to the amp output and the otherone was connected to the 1st speakers terminals - then what becomes of the amp output for the 2nd pair?

Besides with all the past experiments, now the wire is a constraint in the whole setup. I am out of cash, and dont see any new avenues of cash inflow, so I will need to compromise on quality if I want to buy a cable. I hate lousy compromises.

DeF_TecH_FreaK
03-14-2004, 02:46 PM
Or you could get a beast of an amp :) and not worry about the Impedance anymore. Yes, I know, I'm an ass.





You bet. The last one's gone where the amp used to heat and shut down - but now it sounds harsher than before and someone in the forum suggested it could be because of the low impredence that all 5 speakers put together were offering (apart from the suggestion that i was going deaf). Hence this new train of thought about how to increase the final impdence of the bunch by some permutation or combination!



Thats right. The subwoofer is connected from both (L + R) speaker connections of the A speaker pair. Alright so we assume its contribution as negligible and start our assumptions here onwards.



Again, a new problem. Would Series mean that I connect both the + and - terminals of R speaker to the + and - of the L speaker? and then wouldn't both the speakers give the same output - and the purpose of stereo would be defeated - there would not be two channels being played - but the same channel being playd by both the speakers!

Though, I could connect both pair of speakers in this same fashion and end up with a pair each of each channel! But do reflect a bit more on the actual series connection. If only 1 of the speakers were to be connected to the amp output and the otherone was connected to the 1st speakers terminals - then what becomes of the amp output for the 2nd pair?

Besides with all the past experiments, now the wire is a constraint in the whole setup. I am out of cash, and dont see any new avenues of cash inflow, so I will need to compromise on quality if I want to buy a cable. I hate lousy compromises.

markw
03-14-2004, 03:39 PM
I would hope that only the subwoofer is connected to the amp and the mains wre connected to the subwoofer's speaker level outputs.

In any case, a simple formula for figuring out parallel impedance is as follows:

(R1 X R2) or (8 X 8) or ( 64 )
-------------- ------------ ------------ or simply 4
(R1 + R2) or (8 + 8) or ( 16 )

msrance
03-15-2004, 06:54 AM
Thats alright folks, but my problem still remains. Lets see the whole thing all over again. I ask the forum why my amp is sounding harsh and I am told Thats because the total impedence is too less and I should do something abt increasing the impedence.

Now, I want to increase the impedence of the whole bunch by some permutation or combination where I dont need to get bundles of new wire, and I connect the 5 speakers in a fashion that brings the most optimal impedence that can be harnessed after attaching so many speakers together.

and yesa, The sub is connected to the A speaker output on the amp and the speakers are connected from the sub's speaker level output.

Anymore views on this one ?

and yes, what abt the original assumption that the harshness in sound is bcause of the low impedence connected to the amp and not due to HF drivers (tweeters) or hearing loss? [though, I could vouch for the hearing loss not being a factor].

F1
03-15-2004, 07:38 AM
.....
Again, a new problem. Would Series mean that I connect both the + and - terminals of R speaker to the + and - of the L speaker? and then wouldn't both the speakers give the same output - and the purpose of stereo would be defeated - there would not be two channels being played - but the same channel being playd by both the speakers!

Though, I could connect both pair of speakers in this same fashion and end up with a pair each of each channel! But do reflect a bit more on the actual series connection. If only 1 of the speakers were to be connected to the amp output and the otherone was connected to the 1st speakers terminals - then what becomes of the amp output for the 2nd pair?
.......

This is what I meant: From sub out (L channel) connect sub out (+) to Speaker I (+). Then from Speaker I (-) to Speaker II +. Then from Speaker II (-) back to sub out (-). Do the same for R channel. This way basically you add the impedance of Speakers I and II. And yes, you will have one pair of speakers for each channel. I'm not sure how the sound's gonna be but if you like to experiment....