Impedance rise question.

[Caeser2001]

Say you have an option between dual 4 ohm and dual 2 ohm when purchasing the same sub. Theoretically, wouldn’t there be less of an impedence rise with running the dual 2 ohm at 1 ohm vs the dual 4 ohm at 2 ohms?

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[Caeser2001]

Is there such a thing as impedence drop? 1 to .5, 2 to 1?

 

[Mitchell Fosgate III]

At wear and tear, impedance drops. Older cars and premium sounds cars like Chevrolet trucks usually set the factory speaker at less than 4 ohms. 3 or 2. They need the power more for the drive than the radio. So the factory adds an amp. The question 2 ohms have less of rise means that the radio is in tune more at 2 ohms. Not necessarily less to rise in impedance. Just that the radio will adjust more than the speakers impedance. So cars are more for power than radio. These cars then the radio adjust its ohms. Not the speakers. For power reasons by the car. Fairly new car about 2018, I’d go with 4 ohms speakers all 4 of them. Watts: probably same as factory specs. Hard to find, but that will come with research.​

 

[Caeser2001]

This for 1 sub. Still need to purchase an amp. Amp A does 750 watts at 1 ohm. Amp B does 700 watts at 2 ohms. Or am I overthinking? Since most amps are more efficient at 2 ohms vs 1 ohm, should I roll with that? Or, again, am I overthinking? What else can I overthink about for today?

 

[1aespinoza 10+ year member]

Is there such a thing as impedence drop? 1 to .5, 2 to 1?

I have never heard of that happening. When the voice coil moves in the magnetic field, it produces electricity. This is AC current and it works against the input power causing impedance. So AFAIK it is always extra impedance, not less.

 

[Jimi77 5,000+ posts]

Impedance is frequency dependent. Impedance rise or drop is important to take into consideration if your going to do burps, but for music you can ignore it.

 

[shredder1 10+ year member]

Impedance is frequency dependent. Impedance rise or drop is important to take into consideration if your going to do burps, but for music you can ignore it.

This ^^^^

Rise just is, it CAN be taken into account if pure output is the goal but usually a well designed enclosure for the vehicle is more than enough for most. To account for rise takes testing and knowledge.

As unfamiliar with audio as I am I'd wager Impedance drop happens just before you dead short the outputs on your amp I'd think. Sounds like something expensive to me and not repeatable without repair before trying it again.

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