Both drivers go higher in freq

[Virus]

Hello, I'm new to this site, but I've been into audio for a long time, and am even making my own album! I've created an account to post about a peculiar problem.

I have these very cool speakers "ATL CELEBRATION" and they have this problem where both the bass and the tweeter play at a slightly higher frequency than they're supposed to, leading to a saturated tweeter sound and higher bass sound.

I've heard somewhere that an old capacitor can lead to the problem, and after successfully replacing the capacitor, the problem remained.

They still sound really good, meaning that the drivers are probably fine, but I really have no idea what the problem is, any sort of help would be appreciated.

ATL CELEBRATION

• Virus
• Oct 15, 2022
• german

ATL CELEBRATION.
Audax tweeter and a Vifa bass.

 

[Nat]

I don't want to be a pill, but I don't understand what you are trying to get across.
What do you mean by 'playing at a slightly higher frequency', 'saturated tweeter sound' and 'higher bass sound'?
Normally people don't complain about tweeters playing at high frequencies, and your description suggests to me that there are peaks in both drivers' response, but you say they sound really good. So I'm baffled.

 

[elnaldo]

Welcome to AK!

I'd say, if you don't like the way the speakers sound, try to sell them and buy a pair that fits your needs.

I professionally fix speakers and amplifiers, and I receive these kind of inquiries very often, people buying speakers (even expensive ones, several K$), trying then to "tweak" what the designer did. And my answer is always the same. Sell them and buy a pair that you like.

Anyway, a more detailed description of your problem will help to diagnose what's going on.

 

[Virus]

I don't want to be a pill, but I don't understand what you are trying to get across.
What do you mean by 'playing at a slightly higher frequency', 'saturated tweeter sound' and 'higher bass sound'?
Normally people don't complain about tweeters playing at high frequencies, and your description suggests to me that there are peaks in both drivers' response, but you say they sound really good. So I'm baffled.

Understandable, I'm not an expert, so let me try an make it simple.

Let's say you're playing a song, and that song is slightly different on one speaker, but just barely noticeable.

You try an play a different song, and in this song, specific frequencies get hit where one tweeter sounds like its trying to do the impossible, creating sharp, unpleasant sounds.

Now, these speakers have the ability of disconnecting the rear connections to only hear the tweeter or bass separately.

You find out that, playing only the bass on both speakers, one of them doesn't hit as low, while at the same time, you can hear some of the higher frequency sounds it's just not supposed to play.

I Am yet to open these again because of a busy schedule, will do it within this week, and I'll try replacing tweeters to see if its not cracked.

I could replace the bass, but the tweeter's problem is clearer to hear on specific tracks.

 

[Virus]

I

Welcome to AK!

I'd say, if you don't like the way the speakers sound, try to sell them and buy a pair that fits your needs.

I professionally fix speakers and amplifiers, and I receive these kind of inquiries very often, people buying speakers (even expensive ones, several K$), trying then to "tweak" what the designer did. And my answer is always the same. Sell them and buy a pair that you like.

Anyway, a more detailed description of your problem will help to diagnose what's going on.

I love how they sound, the one that works without a hitch sounds brilliant, but one of them has a problem, check the post above, I've written a little more about the issue.

 

[nerdorama]

Are you the original owner or bought used? If used, possibly they were driven hard and a tweeter damaged. Wild speculation on my part. Or something in the crossover could have been damaged by high power. Have you opened them and looked at the crossovers? What is the vintage of these? Can't find much on the web about them.
Good luck,
John

 

[Nat]

That's considerably clearer as to what you mean. One possibility often suggested is that the capacitors in the crossover be replaced, but that is probably not likely to be your issue since the typical reason to recap is that old electrolytic caps have drifted in value or even died. But your speakers look new enough that that shouldn't be an issue, unless the crossover was built as cheaply as possible and low power caps were used. In which case they may have been damaged. So it would be worth looking at the crossover and posting a picture.
But it is worth asking - what amp are you using with these speakers? Is it comfortable with their impedance? Is it powerful enough? It sounds like at least part of your problem is distortion at higher power levels, and the amp is often the issue.

 

[elnaldo]

I´d swap the tweeters to see if the problem follows the tweeter or the crossover. You could do the same with the woofer. Also, playing test tones (one single freq sine waves at different freqs) can reveal problems, something vibrating at certain freq, Voice Coils misaligned, cabinets with loose parts vibrating, even a wire vibrating inside the cabinet can create some noise perceived as a distortion. I've fixed these kind of problems many times.

DON'T PLAY TEST TONES or sine waves at high output levels. They can damage a speaker if playing too loud for long time.

Use a MONO signal to do those tests, or use just one channel from your amplifier, not L y R but just one.

 

[Virus]

Hello, I'm new to this site, but I've been into audio for a long time, and am even making my own album! I've created an account to post about a peculiar problem.

I have these very cool speakers "ATL CELEBRATION" and they have this problem where both the bass and the tweeter play at a slightly higher frequency than they're supposed to, leading to a saturated tweeter sound and higher bass sound.

I've heard somewhere that an old capacitor can lead to the problem, and after successfully replacing the capacitor, the problem remained.

They still sound really good, meaning that the drivers are probably fine, but I really have no idea what the problem is, any sort of help would be appreciated.

ATL CELEBRATION

• Virus
• Oct 15, 2022
• german

ATL CELEBRATION.
Audax tweeter and a Vifa bass.

Update: Unfortunately, it seems like it is the tweeter. We replaced the tweeter and put it on the other speaker, and it still has a problem.

I was so certain that wasn't the issue, but I guess I was wrong.

I should probably sell it

 

[Virus]

My problem is that i don't see what the problem is. It's such a barely noticeable issue, I'm so

I mean, look at it!

I don't see any problems, even the magnet looked fine!

What kind of a specific and barely noticeable issue can a tweeter have?

 

[nerdorama]

voice coil rubbing perhaps. If you have a signal generator, you could loosen the four bolts around the dome and move the dome/voice coil slightly while playing at a low volume to see if the noise clears up.

 

[Virus]

I´d swap the tweeters to see if the problem follows the tweeter or the crossover. You could do the same with the woofer. Also, playing test tones (one single freq sine waves at different freqs) can reveal problems, something vibrating at certain freq, Voice Coils misaligned, cabinets with loose parts vibrating, even a wire vibrating inside the cabinet can create some noise perceived as a distortion. I've fixed these kind of problems many times.

DON'T PLAY TEST TONES or sine waves at high output levels. They can damage a speaker if playing too loud for long time.

Use a MONO signal to do those tests, or use just one channel from your amplifier, not L y R but just one.

The problem persists on the tweeter.
Ive noticed that the voice coil is a bit to the side as opposed to center place.

Could that affect the sound ever so slightly?

 

[elnaldo]

You should disassemble the tweeter to look inside. Many different problems could cause distortion.

A tweeter VC going off center , even if possible, would be quite rare. The VC is very small and light and the glues are strong. But it could be damaged-burned and the wire detaching from the former, or some other problem. Some dirty or debris inside the magnet gap for example. Or simply off center. The only way to see it is looking inside.

As mentioned, one way to center the VC is to play some tones while adjusting the screws.

BE CAREFUL with the faceplate screws. The magnet is very strong and will attract the screws and the tools to the dome. Hold the screws with your fingers and some force and also the tools.

 

[Virus]

You should disassemble the tweeter to look inside. Many different problems could cause distortion.

A tweeter VC going off center , even if possible, would be quite rare. The VC is very small and light and the glues are strong. But it could be damaged-burned and the wire detaching from the former, or some other problem. Some dirty or debris inside the magnet gap for example. Or simply off center. The only way to see it is looking inside.

As mentioned, one way to center the VC is to play some tones while adjusting the screws.

BE CAREFUL with the faceplate screws. The magnet is very strong and will attract the screws and the tools to the dome. Hold the screws with your fingers and some force and also the tools.

Hey, I've disassembled the tweeter and boy is the magnet heavy.

Will I not get electrocuted touching this?
Should is use some protective gear?
I'm also noticing (might not be clear on the image) the yellow sponge specs are stuck on the back of the dome. Can that affect sound by giving it harsh sharpness?

The dome itself looks perfect.

Is there a video tutorial where a man moves the dome around to check sound? I've been trying to find it to no avail.

 

[Virus]

Hey, I've disassembled the tweeter and boy is the magnet heavy.

Will I not get electrocuted touching this?
Should is use some protective gear?
I'm also noticing (might not be clear on the image) the yellow sponge specs are stuck on the back of the dome. Can that affect sound by giving it harsh sharpness?

The dome itself looks perfect.

Is there a video tutorial where a man moves the dome around to check sound? I've been trying to find it to no avail.

I have some photos (the closer tweeter is the one that's fine, and the further one has a problem).
I don't want to replace them, these are killers, I really hope there's something I can do.
Idk how images work on this site so sent these as full.

 

[nerdorama]

Try using some paper to swish through the voice coil gap and see if there is any debris in there. I cut up a coffee filter for this. You might even put a little WD40 on the filter paper so small specks will stick to it. That looks like a big piece of foam to fit under a dome. Could be some flecks of the foam in the gap. If you don't find anything in the gap, then it makes me more suspicious that the coil may have been rubbing slightly. Is there any evidence of rubbing on the the magnet wire varnish? It's hard to tell anything about the voice coil from the straight on view. It does look like there is something on the left side of the VC in the picture. Almost looks like the former is bent over a bit.
John

 

[Virus]

Try using some paper to swish through the voice coil gap and see if there is any debris in there. I cut up a coffee filter for this. You might even put a little WD40 on the filter paper so small specks will stick to it. That looks like a big piece of foam to fit under a dome. Could be some flecks of the foam in the gap. If you don't find anything in the gap, then it makes me more suspicious that the coil may have been rubbing slightly. Is there any evidence of rubbing on the the magnet wire varnish? It's hard to tell anything about the voice coil from the straight on view. It does look like there is something on the left side of the VC in the picture. Almost looks like the former is bent over a bit.
John

I took some more pics of the vc at angles.
BTW, should i replace the yellow sponge, and if so, with what?

Thanks for all the help, I'm more of a computer software guy than an audio guy.
Vlad.

 

[Virus]

I took some more pics of the vc at angles.
BTW, should i replace the yellow sponge, and if so, with what?

Thanks for all the help, I'm more of a computer software guy than an audio guy.
Vlad.

 

[nerdorama]

The VC former does look a little rough around the edge but you'd have to be very careful if you tried to smooth it. Something round and smooth like a pen barrel with very light pressure might smooth it a bit it that is really what I'm seeing. A couple of the pictures do appear to have scrape marks on the inside of the former. Have you tried cleaning out the VC gap? Not sure I would replace the foam unless it is crumbling or hardening. The other tweeter, which you say is fine, probably has an identical piece of foam.

 

[elnaldo]

Leave the foam alone by now. Looks perfectly normal from here.

I agree about a small dent on the VC. Check by yourself, from here is not easy to confirm that.

This is not normal, the VC shows signs of rubbing: