Check your piezo's, Damp your cabs, Follow the plans!
- LelandCrooks
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Re: Check your piezo's, Damp your cabs, Follow the plans!
You can hear high order harmonics. Run a sweep from 2k to 15k. The harmonics will jump out of the horn. Above 12k they're usually quiet and harmless. Anything below 8k is grounds for dismissal.
If it's too loud, you're even older than me! Like me.
http://www.speakerhardware.com
http://www.speakerhardware.com
Re: Check your piezo's, Damp your cabs, Follow the plans!
I am about to start two J12Ls with full Piezo arrays. Is testing Piezos still recommended? I'm getting them from PE.
- LelandCrooks
- Posts: 7244
- Joined: Thu May 04, 2006 9:36 am
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Re: Check your piezo's, Damp your cabs, Follow the plans!
Yes.
If it's too loud, you're even older than me! Like me.
http://www.speakerhardware.com
http://www.speakerhardware.com
Re: Check your piezo's, Damp your cabs, Follow the plans!
Soooo... If I need 32 of them, how many should I get to allow for perfection- 10% or 20% or?
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Re: Check your piezo's, Damp your cabs, Follow the plans!
6-10 extra should be fine...nola50 wrote:Soooo... If I need 32 of them, how many should I get to allow for perfection- 10% or 20% or?
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
Re: Check your piezo's, Damp your cabs, Follow the plans!
Apparently my PC does not generate enough power to drive the Piezos to any great volume. What is a good suggestion for amplifying the test sweeps from the Audion Sweep Gen free program?
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- Location: New Braunfels, TX
Re: Check your piezo's, Damp your cabs, Follow the plans!
I did it with the output from my iPhone.....you should have plenty with the PC.nola50 wrote:Apparently my PC does not generate enough power to drive the Piezos to any great volume. What is a good suggestion for amplifying the test sweeps from the Audion Sweep Gen free program?
6 - T39 3012LF
4 - OT12 2512
1 - T24
1 - SLA Pro
2 - XF210
"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."
Re: Check your piezo's, Damp your cabs, Follow the plans!
Once the volume was cranked up, it all worked just fine.
Out of 42 I have 3 that are questionable after checking them all twice.
Out of 42 I have 3 that are questionable after checking them all twice.
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Re:
Haha!
If you'd have said (typed) nothing, it would have just sat there.
Still, there's valid info in the thread...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
Re: Re:
I just meant JUST my post.... I posted in error, and deleted text with the edit function but could not delete the post. The info in the thread is definitely helpful! I just finished testing 50 piezos with the info here. Thanks to this thread I know that...Grant Bunter wrote: ↑Thu Aug 11, 2022 4:34 amHaha!
If you'd have said (typed) nothing, it would have just sat there.
Still, there's valid info in the thread...
None had reversed polarity
All of them had capacitance between .167 and .120.
All worked.
Maybe I could contribute a rattle test. One that had capacitance of .162, worked and did not have reversed polarity was quieter than the others. It also had something rattling inside. On opening it, the paper cone was bent out of shape. It's my only bad one. Pays to get them from Speakerhardware.com or from Parts Express I guess.
One man's magic is another man's engineering. --Heinlein
1 x DR250
1 x T39
1 x Omni 10
1 x DR250
1 x T39
1 x Omni 10
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- Location: Vancouver BC & Bloomington IN
Re: Re:
For sure. This post helped me build my little test rig that made checking the piezos for my otop arrays easy. Found a fair number of bad ones that Parts Express forgave.
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas