piezo/soft dome tweeter combination

Salas

diyAudio Chief Moderator
Paid Member
2002-10-08 11:31 am
Athens-Greece
They used to do it 20 years ago when the tweeters which had some power handling to speak of hardly had good dispersion.

If you think your system lacks HF, yes you can try out a piezo, its so cheap anyway.

Piezos have impedances in the hundreds of Ohm. You should run a resistor across it in the order of decades of Ohm. Then feed it with a .1 to .22 cap on the plus terminal.

3 things are your playground so to achive good integration.

a. The lesser the resistor the less the dB.

b. The smaller the cap, both less dB and higher cutoff.

c. Positive and negative polarity test to hear for best addition with your tweeter.

I would start with a 33 Ohm across, .22uf, and negative polarity on the piezo.

Good lack.
 
The only reason I can condone this method is because it is cheap, like me. It would never cross my mind to use a piezo again. They are inexpensive for a reason. To me they are nothing more than a poor mans PA tweeter. If your other drivers are of quality then you might be wasting your time with a piezo. Perhaps consider another type of tweeter.

Cal
 

Salas

diyAudio Chief Moderator
Paid Member
2002-10-08 11:31 am
Athens-Greece
The system has enough HF, but it's just an experiment. Maybe it 'adds' something to the sound, or makes the system sound nicer.

Hmmm...when used in PA instead of compression drivers they sound odd. Mainly because of dips in the presence range and super cheap back chambers. Also bcs they only make low 90s in SPL, they push them with various resonance techniques in their chambers, throats and matching horn flares.

When used stripped down as supertweeters they can be surprising. I remember I have listened to an excellent integration in an old speaker British speaker - CELEF PE1- if I remember correctly. Latest good thing I listened to was a super expensive PHY supertweeter using CTS guts.