Anonymous
Anonymous asked in Science & MathematicsEngineering · 6 months ago

Does 500 watt speaker dissipate all that power into heat, obviously yes, right?

Update:

So, do high power speaker coils get hot like induction heater.

Update 2:

Probably vibrating sound helps to cool them to certain degree, but i see testimonies they DO get hot at high power.

Update 3:

"There is very little heat dissipated since the wires used are enameled copper and have a very very low resistance."

That's nonsense, speaker coil has rated impedance, be it 0,5, 1, 2, 4, 8 or more Ohms. This is DC resistance, ohmic losses.

Update 4:

jocelyn just stop embarassing yourself, that nonsense is painful to read.

"The resistance offered by the speaker coil is known as Impedance. It is high and so the DC resistance of 4Ω, 6Ω or 8Ω does not play a role."

Speakers impedance is more than 90% due to it's DC resistance, speaker coils are made with 50 or less turns of thin wire, they have very low impedance and extremelly low reactance especially at audio frequencies.

Lesson for all, do NOT answer if you do not know.

Update 5:

jocelyn I apologize for treating you so harsh, my brother, it's just that your answer is not correct.

Update 6:

Philomel 12.5 RMS lol, look at some dyno tests on youtube and you'll see car and even home amps producing kws RMS.

Relevance
• 6 months ago

A typical 8 ohm speaker will have a DC resistance of around 6 ohms. The rest is reactive and creates a complex impedance vs frequency that a manufacturer tries to keep around 8 ohms. Some are better than others.

In any case that 6 ohms of DC resistance represents a loss and will dissipate energy as heat. So about 75% of the power sent to a speaker turns into heat. The rest turns in to acoustic vibrations. (and I suppose a **very** small amount is radiated as EM.)

• M.
Lv 7
6 months ago

All? No.

Some of the energy is converted into motion.

• 6 months ago

A good part of the energy is emitted as not-sound, yes. 500 watt speakers rarely operate at 500 watts though. 500 watts is the maximum the system will handle without having problems. The "heat" loss is primarily related to the physical movement of the diaphragm(s) (friction) and electrical resistance, which is typically very low. There is not a lot of heat that builds up, it dissipates pretty fast, and there is not a lot of it to begin with. There are also other e-m emissions that occur and are not what we would call "heat". You cannot induce magnetic field variations without generating some sort of em radiation, and a speaker works by converting electrical signals into field changes which cause physical motion to a diaphragm. A lot of the energy just goes out into space. It is not "heat" per se.

• 6 months ago

Most home amplifiers max out at around 12.5 watts RMS, which the standard for measuring power.

The other specs are BS to pump up the numbers to increase sales.

12.5 Watts RMS will damage your hearing in a medium sized room with good speakers.

Some will be heat and some will be Sound power.

• Joe
Lv 7
6 months ago

Some of the electrical energy input goes to making air vibrate (sound). That's mechanical energy released from the speaker into the environment.

But most of the electrical energy input is converted to waste heat. It's nowhere near 500 Watts, continuous, though. Average electrical power for a music signal, even loud music, is going to be closer to 10 Watts. The amplifier and speaker need a lot of "headroom" to handle the rare spike without distortion.

• 6 months ago

That is a peak rating, and is the total power into the speaker at a music peak. The average power is typically much lower, probably less than 1/10 that number. But 50 watts is still a lot.

Some of that power is also in acoustic energy that is dissipated in the room.

If you did try to drive the speaker with 500 watts a steady signal, it would burn up while producing a deafening amount of sound.

Simple math, power in equals power dissipated in the speaker as heat plus power exiting as sound energy. The latter you can get with the efficiency rating of the speaker, which is usually well less than 10%.

• 6 months ago

No. The speaker uses 500 watt power to produce deep base sounds so the power is used for a very short period of time. There is very little heat dissipated since the wires used are enameled copper and have a very very low resistance.

No, again please. The resistance offered by the speaker coil is known as Impedance. It is high and so the DC resistance of 4Ω, 6Ω or 8Ω does not play a role.

When power is applied at 22 hertz to 22k Hz, the impedance due to the speaker coil allows a small current to pass through, creating a powerful magnetic field that causes the cone to vibrate. This power may be 500 watt PMPO but the actual current and power is very much smaller, so the DC resistance does not play a role in heating. Sorry.