It's much much "easier"... 
Never ever overtighten the screws when using drivers with flimsy plastic basket...
I have a nasty basket resonance but only in this one baffle.
I loosened the screws a bit and the resonance was gone for a while but came back, I think because the material is "recovering" i.e. working back to the original form. When the resonance was there again, I pressed down the front frame of the basket with my fingers and the resonance was gone again... I will probably have to play with it a bit and maybe I need a "layer of insulation" between the basket and the baffle, the driver itself only has a very thin layer of sponge.
It's a really annoying problem, especially when you have two identical baffles
Never ever overtighten the screws when using drivers with flimsy plastic basket...
I have a nasty basket resonance but only in this one baffle.
I loosened the screws a bit and the resonance was gone for a while but came back, I think because the material is "recovering" i.e. working back to the original form. When the resonance was there again, I pressed down the front frame of the basket with my fingers and the resonance was gone again... I will probably have to play with it a bit and maybe I need a "layer of insulation" between the basket and the baffle, the driver itself only has a very thin layer of sponge.
It's a really annoying problem, especially when you have two identical baffles
Well, it's weird... I still have the nasty resonance in one of the baffles and have no idea why... a swapped the drivers - no difference, it's the one baffle. I changed the baffle (this is the ugly trial version) - no problems, altough this is the very same material (was cut from the same MDF sheet) with the same cut out. Weird...
The sheet adhesive on the resonating one may have failed in a critical spot. Or it’s interacting with one of the mounting points. 
If your replacement works, you just have to pretty that one up! 😁
This may be moot for you, but I decided to mount the drivers in my OB using silicone o ring washers on the driver screws, in addition to foam gaskets on the driver frames. I’ve been surprised how little these baffles vibrate compared to my Manzanitas.
If your replacement works, you just have to pretty that one up! 😁
This may be moot for you, but I decided to mount the drivers in my OB using silicone o ring washers on the driver screws, in addition to foam gaskets on the driver frames. I’ve been surprised how little these baffles vibrate compared to my Manzanitas.
Yeah... it's not so easy... now I have resonances with the old ugly baffle too
🤪And I think it's cone resonance, no, I'm pretty sure.
Short summary:
- resonance starts in the right speakers FR baffle/driver
- replaced the right driver (thoughtit's damaged), but resonance still here, left driver unchanged, no resonance there
- swapped the baffles, right with the new driver to the left and left to the right, the resonance was now in the left speaker
- swapped the drivers, the new one from the left to the right, the other from right to the left, the resonance is still in the left speaker, so it has/should nothing to do with the driver
- changed the resonating baffle to the old ugly, there are the same resonances at certain frequencies
- why no resonance in the right speaker, it started there!
- can deep frequencies resonate the FRs cone? If yes... is this FR unusable in OB?
- if it's cone resonance... well, I don't know what to do
maybe I should change the distance between wall and speaker in order to "adjust" the timing of the indirect, reflected sound? - it's not funny anymore
What exactly are you hearing? A rattle, a buzz, something else?
Is it frequency dependent?
How loud does it have to play to make this noise? Is it not there at all until some threshold level?
What signal are you using to chase it? Swept sine wave? Old analog signal generators are handy for this kind of investigation, since it's so easy to sweep through whatever range you want.
Have you tried measuring distortion? A nearfield measurement on the driver of interest is usually best, since it puts background noise down far enough that you can get a cleaner measurement (watch the SPL limit of your microphone though if the level is very high).
How much excursion does the driver have at the onset of this "resonance"?
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Many thanks @mattstat !
I would say it's a rattle and it occurs at a certain (but still don't know which one) lower frequency, when playing longer "boomy" bass. I listen at about 78-80 dB(A) and I think it disappears at lower volumes, but I have to check it again tomorrow. The signal was music only, sadly I don't have an audio signal generator.
However, I made a measurement with long sine sweep and there was no distortion, but the level was lower.
The FR has practically no excursion.
Also thanks @duck552 , "something" between baffle and driver was my thought too.
Correction: the measurements were made with the Alpair 12P, not with the SB... cool, I will repeat the measurements tomorrow.
I would say it's a rattle and it occurs at a certain (but still don't know which one) lower frequency, when playing longer "boomy" bass. I listen at about 78-80 dB(A) and I think it disappears at lower volumes, but I have to check it again tomorrow. The signal was music only, sadly I don't have an audio signal generator.
However, I made a measurement with long sine sweep and there was no distortion, but the level was lower.
The FR has practically no excursion.
Also thanks @duck552 , "something" between baffle and driver was my thought too.
Correction: the measurements were made with the Alpair 12P, not with the SB... cool, I will repeat the measurements tomorrow.
You can download a signal generator like this one https://onlinetonegenerator.com/
That will help with the frequency identification
That will help with the frequency identification
The journey will continue
That’s fantastic experimentation!
I like the segmented approach. I wonder if there would be a benefit to having the area of each segment be proportional to the diameter of the driver. That being said, I am not sure intuition is of of any value in this kind of project.
Many thanks @ElArte !
Intuition could work but it must be confirmed by ears and measurements
In case of the baffle/diameter ratio, I wanted to keep the drivers as close as possible to each other, because I wanted a coherent sound. I tried bigger distances with the old one peace baffle and with one or two foam baffles, but the idea was cancelled
Intuition could work but it must be confirmed by ears and measurements
In case of the baffle/diameter ratio, I wanted to keep the drivers as close as possible to each other, because I wanted a coherent sound. I tried bigger distances with the old one peace baffle and with one or two foam baffles, but the idea was cancelled
Now it was a long listening session, and I'm really amazed
The development of the mids is really great, but even more that of the highs, if it would be a completely different speaker.
The stage has now also more space, and the instruments are unbelievable well placed. And yes, more and finer details.
I think the baffle resonance killed all this things to some degree.
The development of the mids is really great, but even more that of the highs, if it would be a completely different speaker.
The stage has now also more space, and the instruments are unbelievable well placed. And yes, more and finer details.
I think the baffle resonance killed all this things to some degree.