Question about Resistance for EE's.

[seg_representin 10+ year member]

I was wondering how you get the resistance that you want. Like for a sub how do they get the 2ohm voice coil, 4ohm voice coils, and so on? I know that resistance depends on the material, cross sectional area, length, and temperature, but i would just like someone to go in a little more depth on it like resistors in a circuit and so on. Sorry if the question is confusing i'm trying to explain it the best i can.

Click to read more...

 

[GemaRastem 10+ year member]

basically they just change the dimensions of the coil as in length of wire/cross sectional in order to increase the resistance at rest while keeping the same parameters of the woofer

 

[bose301s 5,000+ posts]

I was wondering how you get the resistance that you want. Like for a sub how do they get the 2ohm voice coil, 4ohm voice coils, and so on? I know that resistance depends on the material, cross sectional area, length, and temperature, but i would just like someone to go in a little more depth on it like resistors in a circuit and so on. Sorry if the question is confusing i'm trying to explain it the best i can.

You're pretty much dead on. Larger cross sectional area lowers resistance, longer length increases it. Materials with lower resistivity have lower resistance and vice versa. You seem to have the basics down. Basically what a resistor does is convert electrical energy to heat energy.

 

[lilmaniac2 5,000+ posts]

length of the wire in the coil changes which changes the "winding length" which is how tall the copper part of the vc is measured from the bottom of the former up to where the windings stop

 

[Immacomputer 10+ year member]

The resistors in a circuit are processed very differently than voice coils but the idea is relatively the same. It has to do with semiconductor fabrication and the use of silicon (and other products). The cross sectional area and length are the main determinants of the actual resistance. In pure resistors, the doping of the main silicon dye with other materials will increase or decrease resistance as well. The process of making resistors and other semiconductor devices is really interesting stuff with some pretty crazy math and physics behind it.

 

[seg_representin 10+ year member]

Thanks for the replies. Just trying to learn more.

 

[seg_representin 10+ year member]

The resistors in a circuit are processed very differently than voice coils but the idea is relatively the same. It has to do with semiconductor fabrication and the use of silicon (and other products). The cross sectional area and length are the main determinants of the actual resistance. In pure resistors, the doping of the main silicon dye with other materials will increase or decrease resistance as well. The process of making resistors and other semiconductor devices is really interesting stuff with some pretty crazy math and physics behind it.

Yea i've heard the math and physics that goes with some of this stuff is nuts. I like learning about electrical components and how things really work and the math and physics behind it. I know some of the basics, but nothing compared to what i will learn in college. I'm pretty sure that i'm gonna major in EE, but just not sure what exact field i'm gonna go off to.

 

[DBfan187 5,000+ posts]

I forgot. Something to do the the length of the inductor.

 

[nauc 10+ year member]

what about recones

how can you buy a sub from RE and have Fi recone it, wont it mess up the TS parameters, they would have to have the exact parts, wouldnt they

 

[DBfan187 5,000+ posts]

Probably because the guy who designed RE's speakers is also the owner of Fi?

 

[Immacomputer 10+ year member]

Yea i've heard the math and physics that goes with some of this stuff is nuts. I like learning about electrical components and how things really work and the math and physics behind it. I know some of the basics, but nothing compared to what i will learn in college. I'm pretty sure that i'm gonna major in EE, but just not sure what exact field i'm gonna go off to.

It's fun stuff but some of it is hard as hell and very tedious. Depending on the school, you will learn the physics behind the semiconductors in a pure semiconductors class or in your circuit design class. I took a separate course for it and we cover it in less detail in the circuit design course. In the design course, we mainly focused on transistors and the physics behind them for use in circuits. So far, the semiconductor physics course has been on of my favorites in the EE path at my school. I will probably take the grad level semiconductor fabrication course for a tech elective in one of the next few semesters.

 

[bose301s 5,000+ posts]

The resistors in a circuit are processed very differently than voice coils but the idea is relatively the same. It has to do with semiconductor fabrication and the use of silicon (and other products). The cross sectional area and length are the main determinants of the actual resistance. In pure resistors, the doping of the main silicon dye with other materials will increase or decrease resistance as well. The process of making resistors and other semiconductor devices is really interesting stuff with some pretty crazy math and physics behind it.

Most resistors are not made of semiconductor material however. Most are ceramic, metal film and other varieties.

 

[Immacomputer 10+ year member]

Yea, they're still considered semiconductor materials though. Most aren't silicon though if that's what you meant.

 

[bose301s 5,000+ posts]

Yea, they're still considered semiconductor materials though. Most aren't silicon though if that's what you meant.

Well, semiconductor implies that current will flow well one direction but if you reverse the direction it will not flow, or only very little will flow, a resistor for the most part has no polarity meaning it is not a semiconductor technically.

 

[nauc 10+ year member]

Probably because the guy who designed RE's speakers is also the owner of Fi?

iirc, doesnt he do recones for a lot of different companies