quick on-axis comparison - so far able to get three rough pairs from
a lot of 10 units. there's little consistency and response can vary quite
a bit.
Ten Goldwood 1005 1/12 octave smoothing
pairing units 8 & 10
pairing units 5 & 9
pairing units 2 & 6
units 1, 3 ,7 not matched (have to go back and compare to unit 4)
I was able to get a 4th pair out of ten
a lot of 10 units. there's little consistency and response can vary quite
a bit.
Ten Goldwood 1005 1/12 octave smoothing
pairing units 8 & 10
pairing units 5 & 9
pairing units 2 & 6
units 1, 3 ,7 not matched (have to go back and compare to unit 4)
I was able to get a 4th pair out of ten
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Thanks for sharing. Do you feel the results are close enough? Do you see anything physically different about the tweeters or do they look the same?
Freddi,
Can these piezo tweeters be connected directly without an input high pass cap? That is, piezos present a capacitive load anyway right? Seems like a good choice for a super tweeter without any extra parts. Although the -10dB dip at 15khz may be noticeable.
Can these piezo tweeters be connected directly without an input high pass cap? That is, piezos present a capacitive load anyway right? Seems like a good choice for a super tweeter without any extra parts. Although the -10dB dip at 15khz may be noticeable.
At least the dip is consistent! I usually use them with either an 8, 10 or 20 ohm resistor (whichever I have lying around) and a .47 to 1.33udF cap. So all I'm really contributing to the high frequencies is the dip. I guess you could say I like dip.
being like a 0.13uF cap, sometimes its good to have a series resistor. I've seen a problem paralleling them with a resistor and using a high pass cap - the ~4K peak can remain and a saddled response shape appear - perhaps a lot of FR setups are so rough off axis that its better to have some treble than none.
the old CTS KSN 1005 driven with a backwards wired 25 volt matching transformer and LR Zobel on the transformer's "primary" gave over 100dB at 2.8vrms and was pretty flat from 5- 20K. All of Goldwood's 1005 out of these ten look the same including the impression that the phase plug is a bit off center.
CTS KSN1016 on transformer - 1uF
For use as a tweeter, DJK has a good scheme to go with the transformer (use 8R/100uH Zobel for 0.13uF piezo)
Goldwood's 1005 knockoff graph is scary in its own right
the old CTS KSN 1005 driven with a backwards wired 25 volt matching transformer and LR Zobel on the transformer's "primary" gave over 100dB at 2.8vrms and was pretty flat from 5- 20K. All of Goldwood's 1005 out of these ten look the same including the impression that the phase plug is a bit off center.
CTS KSN1016 on transformer - 1uF
An externally hosted image should be here but it was not working when we last tested it.
For use as a tweeter, DJK has a good scheme to go with the transformer (use 8R/100uH Zobel for 0.13uF piezo)
An externally hosted image should be here but it was not working when we last tested it.
Goldwood's 1005 knockoff graph is scary in its own right
An externally hosted image should be here but it was not working when we last tested it.
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I had some TOA pa speakers that used piezo tweeters. They glued the cone of the piezo to the horn, vs just letting the cone hang by the wires.
It is a PITA to do that but it does make them sound better.
It is a PITA to do that but it does make them sound better.
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