[throwaway789657]

Why don't all speakers have some circuitry that blocks any signal that could blow out the speakers? This has always seemed like an absurd state of affairs. It should not be possible to damage speakers by turning the volume too loud.

[londons_explore]

Because knowing exactly how much signal is too much is really hard.

When using the speaker, for some purposes you want absolutely max volume - that involves getting the physical parts of the speaker moving fast and far. Yet move them slightly too fast or too far or do that too often and it'll physically break. Odd effects like resonance mean two very similar looking signals can have widely different physical effects.

The ideal threshold might depend on numerous factors, like temperature and pressure, the age of the speaker, etc. Easy to do in software, impossible in hardware.

So why not just have more margin and make the line between 'loud enough' and 'breaking apart' wider? Well to do that your speaker would need to be physically larger, and space is very much in a premium in many devices.

[throwaway789657]

In no other high-end consumer product would that unreliability be tolerated. Why would you ever run your speakers at a volume that might blow them out depending on what the next bar of the song sounds like? Are you pre-screening every single bit of audio that will get played over your speakers? Otherwise, you should never run speakers at a borderline volume. This protection should be built in to the speaker. No matter how much volume you feed into a speaker, it should not break.

(Of course, you could feed always feed such an absurd amount of power that it would break even the protective circuits, but that ultimate vulnerability is just inherent in the nature of electronics).

[londons_explore]

Dedicated speakers are overbuilt so this won't happen easily.

It's speakers inside a phone or something that are very size-performance limited and are vulnerable to this. Those same devices tend to have advanced processing of audio headed to the speakers to make it sound better and not blow up the speaker.

An old Motorola I had had over 15,000 knobs to tweak in the audio section of the service app...

[throwaway789657]

So if I turn the knob on my a/v receiver all the way up, my speakers won't blow out? I'm obviously not going to try it, but my understanding is that they would get damaged. To prevent this, I set a maximum volume on the receiver's settings to the loudest I'm practically interested in, given the size of the room and such. But that probably means I'm capping my volume a good bit below the guaranteed safe level, which only the speaker manufacturer is really in a position to know.

[grawprog]

When I worked at my old shop I blew out 3 different CD changer stereos and two sets of speakers. One of them even ended up slightly catching on fire...well it was smoking anyway...The machines were really loud, you needed to crank that shit if you wanted to hear it...also I learned that you can't plug 3 sets of speakers into a single one of those things.

[copperfoil]

I may be wrong, but most studio monitor speakers have limiter circuits that prevent damage from high volumes, iirc. E.g. Adam Audio or KRK speakers. These are in $100-200 per speaker

[simonblack]

They have limiter circuits to prevent a very high average power going through them which would overload the speaker-cone's travel limits, or would overheat the voice-coil.

On the other hand, very high-power, short-lived 'transients' are necessary to give proper clarity and realism to the music. Most amplifiers, even very-high power ones usully idle along at about one or two watts or less, but the extra couple of hundred watts available allow lots of 'head-room' for those high-power transients so that they don't get clipped and distorted.

A high-power amp doesn't necessarily sound very much 'louder', but it sounds very much 'cleaner'.

[walshemj]

It happens with DJ sound systems and Band PA's

[throwaway789657]

So this poor reliability is just rampant in the sound industry? Unless there is some reason why such a circuit is not feasible without, e.g., decreasing sound quality. Which is the kind of thing my original question is asking about.

[unparagoned]

It's just the way things are when it comes to speakers. What you are suggesting would be really expensive, unreliable and have all sorts of downsides. It's like asking how comes cars get stuck in traffic, why don't they just make cars fly when the roads are busy...

[throwaway789657]

Do you know where I could learn about the unreliability and downsides of what I'm suggesting? Somehow all of the other electronic gear I own is tolerant of anything short of a lightning strike (and for that, there's surge protectors, which are not that expensive). I'd love to learn more about why speakers aren't the same.

[secnono]

You can absolutely do that but it will make the speaker sound like crap.

[throwaway789657]

I'm curious. Can you say more about why?

[kube-system]

It's mostly a matter of matching the output characteristics of the amplifier to the capability of the speakers... which is what most consumer products with speakers do. Note that the OP concluded that it likely wasn't possible to blow the PC speaker.

[throwaway789657]

If you have your own receiver and your own speakers--a home stereo system, not a PC speaker system--it is just a matter of turning the nob too high to blow them out. With all these wifi-connected receivers these days, I bet if your laptop is compromised, a hacker could turn up the volume and physically damage your speakers. Anyone inside your wifi can cause many thousands of dollars (or whatever your speakers cost) of physical damage. Wow!