Are Piezo Tweeters frowned upon?

nice work fred.
Good job on the drawing for the motorola 1016.

Biggest trouble with retail is people knew that that was a $10 piezo in the $10,000 speaker.
Transformer/zobel/ notch if needed, it would blow away ANY ribbon at a fraction of the cost.

yea.
I said it.
quote me.
Fred has the distortion plots............

I had a motorola 1038A actively crossed 24db LR at 5khz with a 30ohm in series, absolutely stunning.
 
Yeah exactly
Many examples of being crossed too low.
With simple filters.

Like any driver, pound it out of bandwidth
bunch of distortion.

Use a steep filter, and impedance compensation
and cross around 4 , 5 , 6k
feasible to pair with maybe 3" or 4" mid/ wideband

Dirt cheap driver, crossover components would cost more.
And huge trendy 500 watt coils aren't needed.

Be helpful to have impedance measurement
to actually fine tune the crossover.

Dont need transformer, you can create whatever impedance
you want with resistor and cap, or basic passive Zobel
If you try to use conventional crossover without Zobel.
Be almost dead short.
With Zobel and resistor value can make it 6 , 8 , 10 ohms
whatever heck you want. Just important to have
impedance data to fine tune Zobel and crossover

Impedance curve of classic Motorola KSN1041
1697416154302.png


From about 2k be little different than usual , 600 ohms to around 50 ohms

1041 Impedance.jpg

Drop in 8 ohm Zobel around 10 to 18uf to start curve around 2k
Bing...Straight line 8 ohms

KSN1041 Impedance Zobel8ohm.jpg1697418782799.png

Drop in 3rd order 5k crossover
1697419166307.png1697419269252.png
Of course the FRD comes from old Motorola Datasheet
with gracious amounts of smoothing. But that is basic 5k super tweet
Impedance data is important if you add padding, the Zobel needs
fine tuning. All rather simple.
You just cant use conventional crossovers without Zobel
no transformer needed.
1697419375302.png
 
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put 8 ohms in parallel to the piezo between plus and minus and 2.2 microfarad in line before it. this will help against 5khz resonance
Yes, do that , but because the impedance @ 20kHz is now very low, you should add a 3.9 ohm resistor in series
with your positive input connection to protect both amp. & tweeter.
 
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Yeah exactly
Many examples of being crossed too low.
With simple filters.

Like any driver, pound it out of bandwidth
bunch of distortion.

Use a steep filter, and impedance compensation
and cross around 4 , 5 , 6k
feasible to pair with maybe 3" or 4" mid/ wideband

Dirt cheap driver, crossover components would cost more.
And huge trendy 500 watt coils aren't needed.

Be helpful to have impedance measurement
to actually fine tune the crossover.

Dont need transformer, you can create whatever impedance
you want with resistor and cap, or basic passive Zobel
If you try to use conventional crossover without Zobel.
Be almost dead short.
With Zobel and resistor value can make it 6 , 8 , 10 ohms
whatever heck you want. Just important to have
impedance data to fine tune Zobel and crossover

Impedance curve of classic Motorola KSN1041
View attachment 1224116

From about 2k be little different than usual , 600 ohms to around 50 ohms

View attachment 1224125

Drop in 8 ohm Zobel around 10 to 18uf to start curve around 2k
Bing...Straight line 8 ohms

View attachment 1224127View attachment 1224128

Drop in 3rd order 5k crossover
View attachment 1224133View attachment 1224134
Of course the FRD comes from old Motorola Datasheet
with gracious amounts of smoothing. But that is basic 5k super tweet
Impedance data is important if you add padding, the Zobel needs
fine tuning. All rather simple.
You just cant use conventional crossovers without Zobel
no transformer needed.
View attachment 1224135

Without smooting...some from internet.
 

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