Need Help: Possible Tweeter/Amplifier Issue After Sudden Volume Spike

[arj]

If a tweeter blows, the sound will lose energy and sound boring...going shrill is not the speaker issue IMHO.
From your description it sounds like some shift in the EQ ? same thing happening in both speakers would be astronomical rare, forget only for one
If your amp or TV has an EQ try reducing the treble. If it sounds all normal with that, blame it on the gods and dont worry.

 

[availlyrics]

How can a sudden loud advertisement damage the tweeter when I never increased the amplifier volume?

It won't , crossovers protects tweeters to a certain extent from clipping level , highly compressed loud audio.
Use a good quality wired headphones to check the amp.
0dB FS Sine wave testing is very stressfull for speakers, volume should never exceed 25% with short burst of testing lasting not more than 10s. For higher freq between 10K to 20KHz, which maybe difficult to hear for some , one should not raise volume more to avoid damage to tweeters (they are not meant continuous sine wave testing)

https://www.youtube.com/results?search_query=10+khz+test+tone

Downloaded .wav samples are better suited for testing

Custom Sine Tones | Audio Test File Generator

Our waveform generators deliver accurately calibrated sound files, with adjustable frequency and amplitude.

www.audiocheck.net

 

[hifimaddy]

The easiest way to find out is to disconnect your amplifier from everything, including speaker cables. After that, try using Bluetooth or plug your phone directly in and listen with some good headphones. If you still hear unexpected volume jumps, then there might be a problem with your source or the built-in audiolab DAC. Make sure to check the polarity of your speaker cables, and don’t forget to check your remote control first; often, the buttons get pressed accidentally.

 

[SanVJ]

Thanks everyone for the suggestions.

My setup for movies is simple:
Projector (HDMI) → Android Box → Optical out → Audiolab in Integrated mode → Dali speakers.

For music, I use the Audiolab’s Bluetooth connection. No EQ or external DAC.

I received the Fosi ZA3 today, and I can confirm that the amplifier is not the issue, because the speakers sound even worse with the Fosi than with the Audiolab.

With the Audiolab, I also tried changing the power cable and speaker cables.

One thing I forgot to mention earlier: when the incident happened, I had my subwoofer connected to the Audiolab via the pre-out.

When that advertisement played, the subwoofer went crazy, it got extremely loud and started making “boom boom” sounds.

I’ve attached a short video. I’m not sure if it helps, but what I noticed is that after that incident, the speakers haven’t sounded the same. Link

The highs now sound shrill, and to confirm that I’m not imagining it, I invited my brother-in-law to listen. He also said the speakers make a “chill chill” type of sound, so he hears the same issue that I do.

 

[mbhangui]

One thing I forgot to mention earlier: when the incident happened, I had my subwoofer connected to the Audiolab via the pre-out.

When that advertisement played, the subwoofer went crazy, it got extremely loud and started making “boom boom” sounds.

I’ve attached a short video. I’m not sure if it helps, but what I noticed is that after that incident, the speakers haven’t sounded the same. Link

The highs now sound shrill, and to confirm that I’m not imagining it, I invited my brother-in-law to listen. He also said the speakers make a “chill chill” type of sound, so he hears the same issue that I do.

It looks like more that your woofer (low frequency) drivers have conked off. While playing music do the cone material move? If you touch gently the speaker cone, can you feel it vibrating. With a multimeter (resistance measuring position), check the resistance across the two terminals of the speaker drivers. If it is open, then your voice coils have burnt.

Play some song with low frequency content (just drum beats, etc).

 

[Passive_audio_enthusiast]

Tried this method - when I cover the tweeter there is a noticeable difference, so it seems the tweeter is working.

But here's the strange part:

When I cover the tweeter, the overall sound actually becomes smoother and the harshness goes away.

So now I'm confused. Can a partially damaged or failing tweeter still produce sound, but sound harsh?

Partial damage is possible. While playing loud beyond the amps capability, clipping can cause amp to send dc to the speaker. DC won’t be blocked by the capacitor in series with the tweeter or woofer.

The woofers can handle it to some level since the could turns are thicker. Tweeters however has thinner coils turns and thinner conductive coating. Heat produced can melt the coating faster than on woofers. This causes internal short, effectively reducing the number of turns on the tweeter coil.

Your tweeters number of turns is one of the factors determining its frequency response. When it gets reduced, sound changes.

Normally when turns are less, it becomes more „midrangy“ . The more mid range you start hearing through the tweeter, the less sparkle you can notice, since the louder midrange masks the treble, making overall sound more boxy. I don’t know if you can call it harsh.

 

[SanVJ]

It looks like more that your woofer (low frequency) drivers have conked off. While playing music do the cone material move? If you touch gently the speaker cone, can you feel it vibrating. With a multimeter (resistance measuring position), check the resistance across the two terminals of the speaker drivers. If it is open, then your voice coils have burnt.

Play some song with low frequency content (just drum beats, etc).

I already checked the woofers and they sound fine to me.

I tested them by playing low-frequency tones and also by playing songs while filtering everything above 2 kHz.

I also watched some YouTube videos on how to test woofers and manually moved the cones to check for any resistance or scratching noises. There was nothing unusual.

I will test with a multimeter, but I’m not sure which one to buy. Is this one enough? link

 

[mbhangui]

I already checked the woofers and they sound fine to me.

I tested them by playing low-frequency tones and also by playing songs while filtering everything above 2 kHz.

I also watched some YouTube videos on how to test woofers and manually moved the cones to check for any resistance or scratching noises. There was nothing unusual.

I will test with a multimeter, but I’m not sure which one to buy. Is this one enough? link

Yes. That multimeter is enough

 

[SanVJ]

So I did a small test by removing the woofers from one of the speakers.

Here is the video. Is this how it’s supposed to sound?

 

[reachkalyan.kr]

I already checked the woofers and they sound fine to me.

I tested them by playing low-frequency tones and also by playing songs while filtering everything above 2 kHz.

I also watched some YouTube videos on how to test woofers and manually moved the cones to check for any resistance or scratching noises. There was nothing unusual.

I will test with a multimeter, but I’m not sure which one to buy. Is this one enough? link

If you have some old remote battery or weak battery ( partially working battery ) , that also can be used to check the coil continuity blindly by mean time till u receive the multimeter.
New battery also can be used if you know how to trigger for few sec without damaging the coil .

Also similar way remove the tweeter cables ( any one cable from tweeter ) and connect the woofer alone as it was connected earlier and see if you could hear some sound from the woofer .
****Ensure the removed hanging cables are not shorting together***




ATB

 

[SanVJ]

Also similar way remove the tweeter cables ( any one cable from tweeter ) and connect the woofer alone as it was connected earlier and see if you could hear some sound from the woofer .
****Ensure the removed hanging cables are not shorting together***




ATB

Tried this, woofers works and sounds good.

 

[availlyrics]

I will test with a multimeter, but I’m not sure which one to buy. Is this one enough

Good enough accuracy for your needs, as long as you dont test very high level voltage(>200V) or current (>1A) due to safety issues
or low AC RMS voltage (<10V) due to its horrible accuracy.
Meco is a good brand (Rs 1200/-) , if you want a true RMS meter

 

[SanVJ]

Good enough accuracy for your needs, as long as you dont test very high level voltage(>200V) or current (>1A) due to safety issues
or low AC RMS voltage (<10V) due to its horrible accuracy.
Meco is a good brand (Rs 1200/-) , if you want a true RMS meter

The one I shared earlier will only arrive after Diwali, so I ordered this one instead. It will arrive tomorrow.

 

[Passive_audio_enthusiast]

I already checked the woofers and they sound fine to me.

I tested them by playing low-frequency tones and also by playing songs while filtering everything above 2 kHz.

I also watched some YouTube videos on how to test woofers and manually moved the cones to check for any resistance or scratching noises. There was nothing unusual.

I will test with a multimeter, but I’m not sure which one to buy. Is this one enough? link

I am wondering, what at this point are you going to test with a multimeter, if the woofers and tweeters work It simply means there is no burnt coil. Partly burnt coil is hard to understand with a multimeter, as it might change the impedance by few points after the decimal-which can be even within the tolerance of most multimeters. Again, very rare to see woofer getting damaged and the tweeters are fine. To me, like I mentioned earlier, loud burst, can burn tweeter coils even partly. Only solution in that case is to replace the voice coil, or to get a fresh pair of tweeters.

 

[SanVJ]

Received my multimeter yesterday and tried checking the tweeters and woofers.

If I touch the meter probes directly on the tweeter terminals, it only shows a reading if I hold the probe in a very specific position, and even then the value jumps around and never settles. Took a small video.

The woofer seems fine, no matter where I touch the probe on the terminal plate, it gives a stable reading around 7.5Ω.

I thought maybe the tweeter was bad, so I connected a small speaker wire to the tweeter terminals first, and then measured at the other end of the wire. With that method, I get a stable reading of about 4.9Ω.

So just wanted to check, is this normal behavior for tweeters? Do they usually give unstable readings directly with probes but read fine when using a proper wire connection?

 

[mbhangui]

Received my multimeter yesterday and tried checking the tweeters and woofers.

If I touch the meter probes directly on the tweeter terminals, it only shows a reading if I hold the probe in a very specific position, and even then the value jumps around and never settles. Took a small video.

The woofer seems fine, no matter where I touch the probe on the terminal plate, it gives a stable reading around 7.5Ω.

I thought maybe the tweeter was bad, so I connected a small speaker wire to the tweeter terminals first, and then measured at the other end of the wire. With that method, I get a stable reading of about 4.9Ω.

So just wanted to check, is this normal behavior for tweeters? Do they usually give unstable readings directly with probes but read fine when using a proper wire connection?

It looks like you are not making contact properly. Pull out the top plastic cover on the multimeter probe so that you expose more of the metal on the probe

 

[SanVJ]

It looks like you are not making contact properly. Pull out the top plastic cover on the multimeter probe so that you expose more of the metal on the probe

I used ChatGPT, and as per its suggestion, I connected a small speaker wire to the tweeter terminals first and then measured at the other end of the wire. With that method, I get a stable reading of about 4.9 ohms on both tweeters.

So both the tweeter and woofers are good, it seems.

But there is definitely something off with how the speakers sound. I don't know what to do now.

 

[rwnano]

I used ChatGPT, and as per its suggestion, I connected a small speaker wire to the tweeter terminals first and then measured at the other end of the wire. With that method, I get a stable reading of about 4.9 ohms on both tweeters.

So both the tweeter and woofers are good, it seems.

But there is definitely something off with how the speakers sound. I don't know what to do now.

Even I had a tweeter resistance showing as ,4ohms but the tweeter was playing faintly or not at all...so I replaced the tweeter

 

[SanVJ]

Even I had a tweeter resistance showing as ,4ohms but the tweeter was playing faintly or not at all...so I replaced the tweeter

I get it, but in my case the tweeter is sounding as loud as before, but the sound is not the same as before. That's why I'm confused whether to change the tweeter or not.

What if the issue persists even after I change both the tweeters? That's why I'm a bit hesitant.

 

[mbhangui]

I get it, but in my case the tweeter is sounding as loud as before, but the sound is not the same as before. That's why I'm confused whether to change the tweeter or not.

What if the issue persists even after I change both the tweeters? That's why I'm a bit hesitant.

It could be the crossover that has gone bad.