Wire gauge on a simple speaker

• William123
In summary, if you want the resistance to be 8 ohms, you would need a wire with a diameter of 0.45mm. Higher wire gauges will not provide a higher resistance. You can use a wire size that you are comfortable with.

William123

Hey
I've built a speaker and the cone is about 20cm in diameter. I need help choosing the wire gauge for the voice coil though. When I look at this chart http://www.powerstream.com/Wire_Size.htm I can't really see anything that will work. My stereo puts out 50W and if I want the resistance to be about 8 ohms the current would be the sqareroot of 50/8, which is 2,5 (I know speakers are more complicated than this but I'm not there yet). However, according to that chart that would mean I need a wire with a diameter of 0.45mm. The thickness of that wire and the length that I would need to get 8 ohms makes the mass pretty stupid. And on a normal voice coil you only see one "layer" of wire.

Am I supposed to just go with a higher wire gauge (0,2mm) and not play on full volume in order to not burn it? If the wire was about 0,2mm I could get a pretty nice voice coil with only 1 layer of wire. The diameter of the coil is 5cm.

Help is very appreciated.

Edit: It might not be 1 layer after all but it's still less than what I would need in the example above.
If I made a 4-layer coil that's 3cm high using 0,25mm wire the resistance would be 26 ohms and the current would be 1,3A. That wire should handle 0.86A so I'm getting closer lol

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Unless you play slow organ music at full volume, don't worry too much about dissipation in the voice coil. Most music has power peaks ten times or so the RMS value. That means for your amplifier to handle 50 Watts without distortion, you will be running 5 Watts or less "most" of the time.

Since you are designing and building the speaker, use a wire size you are comfortable with; if it burns up, go down 3 gauges in wire size (that doubles the current capability).

William123 said:
Hey
I've built a speaker and the cone is about 20cm in diameter. I need help choosing the wire gauge for the voice coil though. When I look at this chart http://www.powerstream.com/Wire_Size.htm I can't really see anything that will work. My stereo puts out 50W and if I want the resistance to be about 8 ohms the current would be the sqareroot of 50/8, which is 2,5 (I know speakers are more complicated than this but I'm not there yet). However, according to that chart that would mean I need a wire with a diameter of 0.45mm. The thickness of that wire and the length that I would need to get 8 ohms makes the mass pretty stupid. And on a normal voice coil you only see one "layer" of wire.

you are mis-understanding the difference of Impedance and Resistance
A speaker can have an impedance of 8 Ohms ( 4 Ohms and 16 Ohms also common)
BUT its electrical resistance will not be 8 Ohms ( the resistance of the coil). It is likely to be much less, maybe only 1 Ohm or lessDave

Tom.G said:
Unless you play slow organ music at full volume, don't worry too much about dissipation in the voice coil. Most music has power peaks ten times or so the RMS value. That means for your amplifier to handle 50 Watts without distortion, you will be running 5 Watts or less "most" of the time.

Since you are designing and building the speaker, use a wire size you are comfortable with; if it burns up, go down 3 gauges in wire size (that doubles the current capability).

davenn said:
you are mis-understanding the difference of Impedance and Resistance
A speaker can have an impedance of 8 Ohms ( 4 Ohms and 16 Ohms also common)
BUT its electrical resistance will not be 8 Ohms ( the resistance of the coil). It is likely to be much less, maybe only 1 Ohm or lessDave
Thank you, this helped! Calculating the impedance seemed more complicated but hopefully it won't blow up if the resistance of the coil is 1 or 2 ohms. :)

What is wire gauge?

Wire gauge refers to the thickness of the wire. It is typically measured in American Wire Gauge (AWG) or millimeters (mm). The higher the gauge number, the thinner the wire.

How does wire gauge affect a simple speaker?

The wire gauge used in a simple speaker affects the electrical resistance and current carrying capacity. Thicker wire (lower gauge number) has less resistance and can carry more current, resulting in better sound quality. Thinner wire (higher gauge number) has more resistance and may result in lower sound quality.

What is the recommended wire gauge for a simple speaker?

The recommended wire gauge for a simple speaker depends on the specific speaker and its power requirements. Generally, a thicker wire gauge (between 16-18 AWG) is recommended for optimal sound quality.

Can I use a thinner wire gauge for a simple speaker?

It is not recommended to use a thinner wire gauge for a simple speaker as it may result in lower sound quality and potential overheating of the wire. However, if the speaker has low power requirements, a thinner wire gauge (such as 20-22 AWG) may be sufficient.

What are the consequences of using the wrong wire gauge for a simple speaker?

Using the wrong wire gauge for a simple speaker can result in reduced sound quality, overheating of the wire, and potential damage to the speaker or other audio equipment. It is important to use the recommended wire gauge for optimal performance and to avoid any potential hazards.