Is this distortion or something else?

[bachatero]

When I play a 440Hz sine wave test tone through my Kali LP-6v2 speakers, I hear a faint artifact in the background that sounds like a high pitched squeal or noise. I can't tell if it's distortion or not but its pitch changes depending only on the volume of the test tone, and that pitch change can't be a change of the 440Hz's harmonics because I can change it finer than a harmonic could possibly go. It goes away at full volume and is loudest near half volume. I also know it's not because of the Motu M2 or my PC they're connected to because the same thing happens when I plug in my phone directly to the speakers.

Does this happen to anyone else?

P.S. I can sometimes hear it in actual content, but like I said, it's faint.

 

[SIY]

When I play a 440Hz sine wave test tone through my Kali LP-6v2 speakers, I hear a faint artifact in the background that sounds like a high pitched squeal or noise. I can't tell if it's distortion or not but its pitch changes depending only on the volume of the test tone, and that pitch change can't be a change of the 440Hz's harmonics because I can change it finer than a harmonic could possibly go. It goes away at full volume and is loudest near half volume. I also know it's not because of the Motu M2 or my PC they're connected to because the same thing happens when I plug in my phone directly to the speakers.

Does this happen to anyone else?

P.S. I can sometimes hear it in actual content, but like I said, it's faint.

I tried this just now with the original LP-6. Didn't get that. What program are you using to generate the tones?

 

[bachatero]

What program are you using to generate the tones?

I use this mostly: https://szynalski.com/tone#A4,v0.95 but it also happens in Audacity.

 

[bachatero]

Found something that sounds similar: Am I crazy??? Kali Lp-6V2 : audioengineering
However, the linked recording is gone so I can't compare it. It almost seems like it could DSP quantization noise?

Anybody else around here have the v2 version?

 

[kemmler3D]

Quantization noise sounds like noise, so that's probably not it.

Is the noise definitely coming from the speaker cone, or just the speaker in general? Is it coming from both speakers or just one?

The fact that the frequency of the noise varies with amplitude (power) but not frequency makes me think something might be wrong with the amp or power supply.

 

[Keith_W]

I don't know enough about amps. @SIY do you think this could be some kind of negative feedback issue with the amp, given that the pitch change varies with volume?

 

[holdingpants01]

Is it apparent on both speakers? Did you test them one at a time? Is it possible there's something rattling in the room? Can you record it?
They have a rather extreme port resonance but closer to 650Hz

 

[Davide]

When I play a 440Hz sine wave test tone through my Kali LP-6v2 speakers, I hear a faint artifact in the background that sounds like a high pitched squeal or noise. I can't tell if it's distortion or not but its pitch changes depending only on the volume of the test tone, and that pitch change can't be a change of the 440Hz's harmonics because I can change it finer than a harmonic could possibly go. It goes away at full volume and is loudest near half volume. I also know it's not because of the Motu M2 or my PC they're connected to because the same thing happens when I plug in my phone directly to the speakers.

Does this happen to anyone else?

P.S. I can sometimes hear it in actual content, but like I said, it's faint.

A similar thing happened to me with my old NHT C3.
With normal music I didn't notice anything, but with a pure mid-frequency tone or with a sweep, at a certain point one of the two speakers emitted a sort of second overlapping tone, acute, highly located in the mid driver.
It was not harmonic distortion, and was not showed in the frequency response. Yet it was very very audible.
I have never been able to measure it. I just got the mid driver changed and it disappeared.

 

[Sokel]

Is it on both speakers (each of them ) ?

 

[LIΟN]

Can you record it simply?

 

[bachatero]

Is it on both speakers (each of them ) ?

Is it coming from both speakers or just one?

This happens on both speakers.

Can you record it simply?

Can you record it?

Enjoy!

 

[kemmler3D]

Q) does the noise happen with tones other than 440hz or is it only with specific frequencies?

 

[bachatero]

Q) does the noise happen with tones other than 440hz or is it only with specific frequencies?

It's also noisy with 200Hz and 10000Hz, but for 10000 there's less of a tone and more broad spectrum noise.

 

[kemmler3D]

It's also noisy with 200Hz and 10000Hz, but for 10000 there's less of a tone and more broad spectrum noise.

This seems like a good clue... but my signal / engineering chops are too weak (read: nonexistent) to understand what it means.


I still think something might be going wrong with the amplifiers, (frequency of noise changing with amplitude) but since it's both speakers, it implies the problem is upstream from the amplifiers, I guess?

So maybe there is some weird noise or DC offset in your power that the speaker amps don't like?

 

[bachatero]

Could it be actual "dirty power?" I haven't ever considered it until now because most of the time it doesn't matter at all, but if my power really is noisy, then that could be just the problem. However, I don't know how to measure it outside of using my oscilloscope which I'm mildly scared of doing due to the voltage requirements.

 

[kemmler3D]

Could it be actual "dirty power?" I haven't ever considered it until now because most of the time it doesn't matter at all, but if my power really is noisy, then that could be just the problem. However, I don't know how to measure it outside of using my oscilloscope which I'm mildly scared of doing due to the voltage requirements.

You will want to ask someone who knows what they are talking about, especially if you are risking more gear...

But what you are describing doesn't sound like faulty drivers to me, it doesn't sound like a DSP/DAC problem, and if the sound comes from both speakers then both amps would have to have the same failure... which would be surprising. I could easily be missing something but that's what I would be looking at, upstream from the speakers somewhere.

 

[bachatero]

Looks like my power isn't so hot:

If the amplifiers on the Kalis are bad enough to pass this noise through, then that's not so nice. Should I just get a power conditioner and see if it helps?

 

[kemmler3D]

Looks like my power isn't so hot:
View attachment 377847
If the amplifiers on the Kalis are bad enough to pass this noise through, then that's not so nice. Should I just get a power conditioner and see if it helps?

Honestly I do not know enough about what power ought to look like to say. I would just try different outlets in the house first to see if anything changes.

 

[pjug]

This happens on both speakers.


Enjoy!

I think it is just 3rd harmonic (besides some noise and clicks). Apply a high pass filter to your file (I used 800Hz 48dB HP in audacity, applied 2X). Then see if it still sounds like the pitch is changing.

 

[SIY]

I don't know enough about amps. @SIY do you think this could be some kind of negative feedback issue with the amp, given that the pitch change varies with volume?

Hard to say without hooking up a scope. Almost like a BFO in shortwave.