hay guys dumb question but I'm not really clear with ohms and how they work? anyone know how they properly work?

cheers

it's impedance coils on subs / speakers all have different impedances or you can wire them together to raise and lower the total impedance

www.realmofexcursion.com

First off, you don’t need to understand everything about Ohms law, to be able to use it, but you need to get the ohms right in order to get the best, and safest output from your amp/s and sub/s (ohms applies to all speakers, lows, mids, highs…)

There are a few things you need to know to use it right.

The first thing you need to know is the difference between a Parallel Circuit, and a Series Circuit. You probably already know the difference between the two, but just forgot witch one is which. So here is a little reminder.

Parallel is running all of your + connections together, and all you - connections together. (setting up your subs in a parallel circuit will lower you ohms load, but we will get to that latter)

Series is running + to - to + to - to + to -… (setting up your subs in Series will raise your ohms load, we will get to that to)

Now you need to know the Ohms ratings on your sub/s and amp/s…

A sub should only have one ohms rating, (1,2,4,6,8,10...) the most common ohms rating for a sub is 2 or 4... Wile an amp can have more than one ohms rating. It is very important to know what your lowest ohms rating is on your amp. For example, If your amp’s lowest ratting is 4 ohms, and your sub configuration is lower than 4 ohms, (worst case scenario) you can blow your amp, (best case scenario) or your amp will cute out.

Calculating ohms is easy, it just depends on if your running a your subs in, Series, Parallel, or both.

Series: Raising the ohms load

Lets say you have two SVC (single voice coil) 4 ohm subs. If you run them in a series circuit, you will raise the ohms load on the amp to 8. All you do in a Series Circuit is add the ohms of the subs together… that’s it.

You can run as many speakers in a series circuit as you want without hurting your amp.

There are two main up sides to this, and one main down side.

1: If you have an amp with a minimum ohms rating of say, 4, but you have a sub with an ohms rating of say, 2, all you would have to do is add another 2 ohms sub in series. This will bring the ohms load on the amp up to 4, and wont damage your amp. (2+2=4)…

the main down side to this is that your subs have to share the amp’s power… Say your amp puts out , 400 rms, each sub would receive 200rms. So if you had a pair of subs that where rated at say, 400 rms, you would be under powering them, that’s not bad for the subs, but you will sometimes find yourself cranking the volume to get your subs moving.

2: If you have a Powerful amp, say 2000 watts rms @ 1 ohm, 1000 rms @ 2 ohms, 500 rms @ 4... And some lower rated speakers, say 250 watts rms @ 2 ohms, then you would want to run 2 of them in series. This would bring the load on the amp to 4 ohms (2+2=4), and would lower the amps output to 500 watt (which would be split by the subs into 250 watts each).

Parallel: Lowering the ohms load

Now if you take those same 2Ohm subs and wire them in Parallel, you will lower the Ohms load on the amp to 1 ohms. For the math, all you do is take the ohms of one sub (2) and divide it by the number of subs (2) 2/2=1... that’s it. (the math only works if the subs have the same ohms rating as each other.)

The up side to this is that each sub is getting a dramatic increase of power from the amp. So say you have that same 400 rms amp, running those same 400 rms subs, both subs would be getting 400 watts. Basically you would be getting 800 watts worth of output. (not that you would find many 400 watt amps that would be able to handle that.)

However if that amp could handle 1 ohm, It would most likely be rated at or around 800watt rms to make it more tempting to the consumer.

That’s why the rms output rating of most amps increases dramatically as the ohms rating decreases. (exp. db platinum 1200.1, 300rms@4ohms 600rms@2ohms and 1200rms @1ohm)

In short, Parallel = more output!

The down side is that if your amps lowest ohms rating is 4, you would be torturing the poor thing with a 1 ohm load, remember Do Not go under your amp‘s lowest ohms rating…

Need to knows

Now lets say you have a sub with more than one voice coil, lets say it is a DVC (dual voice coil) and it’s rated at 4 ohms. Basically you have two subs in one, each voice coil is like a sub, so all you have to do is the same thing you just did.

The ohms rating of multiple voice coil subs is the rating of each voice coil, but the watts rating is for all voice coils combined.

(DVS, 2 ohms) Wire the voice coils in series and you will have 2+2= 4ohms. Weir them in Parallel, you will have 2/2=1ohms

Important! If your sub/s have more than one voice coil, make sure you are always using all of them. You can damage your sub if you don’t. (That is a direct quote from alpine)

Not all amps carrier there lowest ohms rating when they are bridged, so be careful, KNOW YOUR GEAR! For this reason I recommend Mono blocks when running subs, most of them are less picky about ohms, and can carrier much lower ohms load.

Hope that helps

Wow, looking for some info on coil overs and come across the best ohm breakdown ever...this needs to be a sticky!

Can't believe this threads nearly 3 years old

I've actually been studying Ohm's and resistance for the past 2 months, fun stuff..

Have you learned that you can't make 400W into 800W yet?

Have you learned that you can't make 400W into 800W yet?

Perhaps a good follow-on would be to look at how to measure true power levels and also the effect of inefficient speakers?

Just as a starter, when comparing speakers, look at how efficient they are a converting electrical energy into sound. Usually the figure is quoted as a sound level, measured at 1m from the speaker for a given input power and frequency range eg 89dB at 1m. The higher the number the more sound you get for your watts put into the speaker. Worth remembering that a dB (deciBel) scale is not linear and neither is the human ear; to double the volume you need 10 times the power!

Also look at how amplifiers are rated, the most accurate figure available is usually the RMS power rating. 4000Watts peak music power means nothing if the true RMS rating of the amplifier is only 10Watts per channel. Also think, is the power supply in a car going to deliver 4000Watts to the amp? Well not for long!