This is true for this style piezo. But for the larger style ( e.g. https://www.parts-express.com/GRS-P...-Tweeter-Similar-to-KSN102-292-444?quantity=1 ) they come apart more completely. Unscrew, and the horn / phase plug comes off as one piece, and then the piezo element + diaphragm come off, and the back comes off as a cap. More places to potentially leak air, but allows easy access to the back of the piezo and diaphragm. I considered unsoldering mine to reach the back but figured I would melt the plastic housing. I've already picked up some of these larger ones to experiment with. In addition to potentially being more leaky, they also seem to have more molding flash on the plastic parts. But more friendly to mods, and the plastic is thicker.
I see the foam and rubber dampers on the diagram in post 2. If anyone has pictures or more detail about these parts I'd love to know about it. Apart from dryer lint
which actually seems like a really good density for this sort of thing. I've been considering what sort of material (and how to attach) to use for the back side of the piezo element.Yes, I think unfiltered the LF signal doesn't make sound but still uses up the deformation range of the piezo element.
Yes, but it depends on the inductance. For the same core: higher inductance = lover rated amperage (saturation)
You don't need them for a tweeter filter - they are more expensive. If you are willing to pay more, air core inductor is much better.
With the same small ferrite core, rated amperage is between 0.77 and 0.85 A for inductances between 0.22 mH and 0.33 mH.
0.33 mH, 850 mA, $0.68
https://www.digikey.com/en/products/detail/bourns-inc/RLB0913-331K/6677227
0.27 mH, 770 mA, $0.42
https://www.digikey.com/en/products/detail/bourns-inc/RLB0914-271KL/2352778
0.22 mH, 800 mA, $0.42
https://www.digikey.com/en/products/detail/bourns-inc/RLB0914-221KL/2352777
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So, no further development, but I've learned a little more about phase in REW. I had thought that 'compute minimum phase' would remove the distance delay in the phase of my measurement. But I guess not? Here is the measurement with phase as taken...
and the notes that came up with the measurement say it has a delay of 3.1342 ms / 1.075 m / 3 ft 6.3 in. This is with a 2 channel capture with a mic and a timing ref channel. I left the delays in for my XSim work.
I can go to "actions" (gear icon, above graph on R) and select "offset t=0" and change that 0 to equal the time reported...
And now I see a phase flip at the XO point, which was what I had expected. And I think this is "phase" for the speaker.
But there is (after REW generates it) Minimum Phase and Excess Phase. I had kinda thought a speaker was a minimum phase system, so I am a bit confused about what these things mean WRT a measurement.
Min phase -
Excess phase -
Hmmmmmm... I've read a bit about it, but don't quite have it figured out. I'll continue to look for an explanation that makes sense to me.
and the notes that came up with the measurement say it has a delay of 3.1342 ms / 1.075 m / 3 ft 6.3 in. This is with a 2 channel capture with a mic and a timing ref channel. I left the delays in for my XSim work.
I can go to "actions" (gear icon, above graph on R) and select "offset t=0" and change that 0 to equal the time reported...
And now I see a phase flip at the XO point, which was what I had expected. And I think this is "phase" for the speaker.
But there is (after REW generates it) Minimum Phase and Excess Phase. I had kinda thought a speaker was a minimum phase system, so I am a bit confused about what these things mean WRT a measurement.
Min phase -
Excess phase -
Hmmmmmm... I've read a bit about it, but don't quite have it figured out. I'll continue to look for an explanation that makes sense to me.
I've no measurements on this one - but it sounds really good and better than a 5x KSN1016 array on stepup
One KSN1016 Motorola) on the 5 watt tap of a 25v matching transformer. The 8 ohm tap is used for the primary and has 7.2 ohm/100uH Zobel - - crossover is all I have ~1.3uF cap. The wideband in the little Karlson K12 is Celestion's K12H-200TC. There's 22 ohms in series with the piezo.
One KSN1016 Motorola) on the 5 watt tap of a 25v matching transformer. The 8 ohm tap is used for the primary and has 7.2 ohm/100uH Zobel - - crossover is all I have ~1.3uF cap. The wideband in the little Karlson K12 is Celestion's K12H-200TC. There's 22 ohms in series with the piezo.
