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Old 17th March 2012, 02:31 PM   #1
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Default Measuring parameters For Dual Voice Coil Subs

Hi ...

I need some help ... how to measure the parameters for a dual voice coil sub ... should i parallel the coils or series connect them when taking T/s parameters for them ... ???


thx .....
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Old 17th March 2012, 06:10 PM   #2
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Mass and compliance do not change.
A few simple calculation shows that the efficiency does not change
T/S parameters do not change.
What change is sensitivity. Paralleling coils allow four times more current to drive the motor than connecting them in series.
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Old 17th March 2012, 07:03 PM   #3
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For a DVC Sub, TS parameters change as follows(Compared to one coil connected) [ In series] 1/2 Qes, 2(RE), 2(LVC) .[ In parallel ] 1/2(Qes), 1/2(RE), SPL +6 Db.




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Old 18th March 2012, 03:12 AM   #4
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Ok .... if that mean now i have a car DVC sub .... if i wire them to a car amp (in parallel) .... does it means i can improve its Sensitivity ??


The pic attached showed the efficiency is 95db/W/M

Another pic showed the driver wired in parallel currently ....
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Last edited by dannyjmf; 18th March 2012 at 03:14 AM. Reason: typo error
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Old 18th March 2012, 05:18 AM   #5
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The sensitivity changes, but the efficiency does not.

Your amplifier must be able to cope with the much heavier load, say a 1Ω load vs a 4Ω load.
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Old 18th March 2012, 08:38 PM   #6
OscarS is offline OscarS  United States
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Exactly, the sensitivity increases ONLY because of the lower impedance causing the amp to put more power out. So it's louder not because the speaker magically became more efficient, but because parallel wiring in a way is like turning the volume knob up.

That is why djk emphasized sensitivity and efficiency; they are not the same thing. The "spl" you see on the box is not efficiency, it's sensitivity, likely at 2.83V which will feed a speaker more than one watt if the impedance is lower than 8 ohms.

Last edited by OscarS; 18th March 2012 at 08:42 PM.
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Old 18th March 2012, 11:41 PM   #7
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Quote:
Originally Posted by OscarS View Post
Exactly, the sensitivity increases ONLY because of the lower impedance causing the amp to put more power out.
Even more exactly, the sensitivity for a given voltage increases because the lower impedance allows more current into the motor, hence more force on the cone,
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Old 18th March 2012, 11:44 PM   #8
OscarS is offline OscarS  United States
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even MORE more exactly, it doesn't just allow it, it forces more current into the motor!
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Old 20th March 2012, 03:41 AM   #9
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No, you guys missed the little phrase "(Compared to one coil connected)"

But DVC subs are generally not going to give good results with just one coil.

I can tell you from years of measuring that you will get 1 or maybe 2 more maximum decibels from loading down an amp that much. Even amps rated down to 1 ohm will put out more than rated into 2 or 4, so you don't really get double or quadruple the power at all. You just run the amp a lot hotter and suck a lot more current out of the battery.

You'd actually be better off buying a bigger amp to run the subs in series, in theory.

But really you need to tell us model numbers and specs if ya got 'em of the subs and amp(s). You have 1 DVC? And how many channels is your amp(s)?
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Old 20th March 2012, 04:09 AM   #10
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Currently only 1 DVC sub i am using ... The subwoofer i bought i think is a china branded ... so i think i really need to measure the parameters myself .... then my car amp i dont really know the actual wattage it is rated ... but it has 2 channels and it writes there 500W ( a small one )

These are the troubles here ...( as information not enough and dont know can be trusted or not ) .....
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