Sudden high volume is dangerous for speakers?

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I guess this has happened to many:


Although I always take precaution to always leave the volume knob of the amplifiers at a minimum when I finish listening, sometimes I forget it.
And then, it happens that when I connect the smartphone, to listen via Spo ...y , and press your finger index on the symbol of the interface to send the signal to the sound system, the Dac Oppo connects and booooooooooooooooooooommmmmmmmmm !!!!! :boggled::shutup:

Last night I almost suffered a cardiac arrest, the adrenaline shot threw me like a spring towards the volume knob.

Then there is a question for connoisseurs here, can the speakers be damaged? Apart from the violent mechanical stress on the spiders and wings of the speaker, can the electric shock on the coils cause sudden heating and thermal damage?
Are any of these two failures more likely?
Both alike can happen?
There is no risk because the speakers are prepared for this?

P.S:
To make matters worse, my DTQWTII does not have a pass filter in the JA8008, the L2011 inductor allows the passage of the entire signal! Troels points out that "the best step capacitor is the one that does not exist", I understand, but when these things happen to me I wish I had it .....
 

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Most speakers will survive a short transient higher than their rated continuous power rating, if the speakers have only just been turned on then appart from possible mechanical damage if they are driven past their excursion limits, you probably won't burn out any voice-coils.

In my experience the thing that has killed drivers is when the volume level has been turned up above the level where the amp starts clipping. Many a tweeter (and the occaisional midrange) was fried in my uni days because someone at a party decided it wasn't loud enough and turned the amp up past the "thin blue line" (a piece of blutac on the volume dial which was the not past here point, and the exact point where a full 2V input would drive the amp into clipping). This was a 100W / channel amp. It would play for hours without a problem just below clipping, but as soon as it started clipping tweeters would pop.

One low cost solution is to put a polyswitch in line with the speakers, many people will not consider them hifi, but for a speaker at risk I think they are worth it. Once I got some (I had different ones per driver) I never fried another driver.

Tony.
 
Yes, I know the issue of clipping, it is a potential killer for the thin wires of tweeters especially.

In my case, I am more concerned about the midrange/bass that, as I mentioned, does not have a pass filter, and the amplifier is of valves, it does not suffer from the problem of crossing, I think ... I would have to review a bit of theory, it is a Push Pull, it could be ..... gg
 
How much power in that thunderclap of yours?

All wire will act like a fuse if hit with a big enough burst of current.
Speaker cones can be ripped away from the frames.
Voice coils can be ripped from the cones.
Voice coils can be left off centre.

So yeah, you can blow your speakers that way...
If you have enough power.
 
Many a tweeter (and the occaisional midrange) was fried in my uni days because someone at a party decided it wasn't loud enough and turned the amp up past the "thin blue line"

1) I wish I had a dollar for every time I've seen that one.

2) I never understood that. What's the point of inviting over 50 of your best friends then turning the music up so loud they can't talk to one another?
 
" One low cost solution is to put a polyswitch in line with the speakers, many people will not consider them hifi " ....


I am one of them ...... I have a couple of Technics SB1950 that were incorporated, it may not be such a bad idea, if they did .....:D
 

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How much power in that thunderclap of yours?

All wire will act like a fuse if hit with a big enough burst of current.
Speaker cones can be ripped away from the frames.
Voice coils can be ripped from the cones.
Voice coils can be left off centre.

So yeah, you can blow your speakers that way...
If you have enough power.

There are 38 watts of tube ...... but the JA8008 speaker is not manufactured anymore, Troels replaced it with an "improved" model, the HMQ, but it is not a direct replacement, the cross and the front panel must be modified. ..... hence my concern.

It would seem that they survived, today I will gently push them with my hands to see if they scrape the coils.
 
Last night I almost suffered a cardiac arrest, the adrenaline shot threw me like a spring towards the volume knob.

Then there is a question for connoisseurs here, can the speakers be damaged? Apart from the violent mechanical stress on the spiders and wings of the speaker, can the electric shock on the coils cause sudden heating and thermal damage?
Are any of these two failures more likely?
Both alike can happen?
There is no risk because the speakers are prepared for this?
There is a risk of damaging your speakers because you took them by surprise?
 
I can understand overdriving them etc, but taking them by surprise?

:no:Jokes aside, the one that was taken by surprise was my cardiovascular system .....


Any scientific opinion about my concern?
For example :

What is the mechanical tolerance of spiders and wings in relation to speaker diameter?

What is the thermal tolerance to these energy shocks without warning? That is, the high temperature varnish needs a period of progressive heating as the filaments of the tubes to not succumb?

Let's be serious, please, they are my speakers and I love them, almost, almost as much as my dear wife.

And if we measure it in time of pleasure granted, as my chronological age progresses, my cabinets carry those of winning.....:D
 
I had four Fane 12-50WRMS speakers and a 225WRMS amp in the 1980's for my mobile disco. The speakers were thrashed at every gig but never failed despite the amp being a little too powerful for them.

And what would be the conclusion? :(

I represented (among other brands) many years ago Phase Linear and Electro Voice in my shop (PA Line) and when the PL was overexposed it generated direct current to the speakers.
They usually failed, both of them.
The boys in the nightclubs complained that I sold them "garbage" and demanded a free repair.
 
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1) I wish I had a dollar for every time I've seen that one.

2) I never understood that. What's the point of inviting over 50 of your best friends then turning the music up so loud they can't talk to one another?

If it is any consolation, none of them were MY parties (I lived in a 15 sq M bedsit) :D But I did have some ~90db efficient three way speakers mated with a 100W amplifier, which I was asked many times to bring to other parties.

Even at quite a bit less than clipping levels it was adequately loud, but some people just want it louder.

One thing I should qualify (and the reason I specified it was a 100W amp) is that clipping alone is not enough to fry the tweeters, the clipped waveform delivers more power to the driver than a non-clipped one, with bass note clipping causing harmonics that make it to the tweeters) but if the overall power of the amp (even if clipping badly) is below the power capacity of the speakers it won't fry the voice coils, it will just sound terrible.

@academia50 For woofers I would suggest that mechanical rather than electrical damage is the most likely in your situation, and even then, if the amp is capable of pushing your drivers to their physical limits, then your probably shouldn't turn it up so far in the first place... I guess maybe you had some very low level material and had turned up higher than normal...

You may want to have a read of Pano's gain structure article. What is Gain Structure? - diyAudio

Tony.
 
@academia50 For woofers I would suggest that mechanical rather than electrical damage is the most likely in your situation, and even then, if the amp is capable of pushing your drivers to their physical limits, then your probably shouldn't turn it up so far in the first place... I guess maybe you had some very low level material and had turned up higher than normal...


Tony.

It was an oversight that had already happened to me, but this time, the volumes of all the components had been very high. By custom I always have the volume of the smartphone and the volume of the Dac to the maximum ....

A conventional SS amplifier AB will almost certainly cut past a certain volume, that's why most sound so bad (sorry, but I'm decidedly a convert from the SS to the tubes), I think it would have been a catastrophe if it had been an Akai AA5810 amplifier that I knew how to have. With the NAD 3020, I might have dodged it, because it was a much higher development. And I'm talking about 50 Watts Rms against 20!
Keep in mind that my satellite cabinets have a lot of efficiency (95 DB), in addition two JBL "vintage" subwoofer of 96 DB each and the 250 Watt plate amplifier were connected, at medium volume, as I normally use, everything was a tremendous rumble, as I said, almost run out of a very valuable forum participant .....:rolleyes:
Regards Tony :)
 
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