Piezo VS voice coil tweeters

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The genuine powerline have a small bulb and round PTC resistor. They also have damping fibre and small flat balance weights. The plastic is accurately moulded, there is a proper gasket and they feel weightier than the copies. The fit of parts is good.

The others I have bought do not have these things and had spilt glue, offset piezos, moulding flash and no damping etc. They look OK on the outside, but just garbage inside. All in the bin now.

If yours are all built square and have no obvious defects you may get some use out of them.
 
Warning: Tweeters of "GRS" brand are of low quality and sound bad (although slightly better than those without brand,Chinese trash on Ebay or Aliexpress ).I did some tests with them, I also opened them seeing the poor quality of the construction (small an scrached piezo element 22mm. diameter) : absolutely disappointing
The best brand was and remains MOTOROLA, although sold at a high price.
In second place are the Goldwood brand tweeters and in third place, those branded Monacor (Germany).
Buying unbranded tweeters or different brands means buying garbage !
 
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I got these:
GRS PZ1188 Piezo Horn Driver Similar to KSN1188A
GRS claim these are the exact replica and specs from the CTS but with a larger ceramic disc. I open it up and saw some sort of small cap or resistor soldered inside...
Warning: Tweeters of "GRS" brand are of low quality and sound bad (although slightly better than those without brand,Chinese trash).I did some tests with them, I also opened them seeing the poor quality of the construction (small an scrached piezo element 22mm. diameter) : absolutely disappointing
The best brand was and remains MOTOROLA, although sold at a high price.
In second place are the Goldwood brand tweeters and in third place, those branded Monacor (Germany).
Buying unbranded tweeters or different brands means buying garbage !
 

ICG

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The best brand was and remains MOTOROLA, although sold at a high price.

I would not buy Motorolas anymore. I've seen faked ones, the Motorola logo seemingly stamped with a hot metal over other logos or on random places. Sooner or later there will be better fakes and the Motorolas are becomming too expensive anyway, even without the risk of buying a fake.

Besides that, a lot of the old ones got soldered on. Unfortunately, the heat on the latches creeps up the leads and destroys the crystal structure if it gets too hot or the soldering iron is hold onto the latches for too long. The result is they will be a lot quieter or don't work at all anymore. The same applies ofcourse to new piezo tweeters too, so don't solder them on, use crimp on connectors on your cables and don't re-solder the leads onto it because the solder connection 'doesn't look good'.

In second place are the Goldwood brand tweeters and in third place, those branded Monacor (Germany).

No, they are not. Both brands are trade companies and get them from the same factory and they are of the same quality. If you find some better or worse it's the normal production tolerance range. They don't have every model the other got and some look a bit different in detail.
 
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Voice coils, with their endless crossover problems, must be superior to piezo-driven tweeters, since most, if not all of you use them. Is their non-linearity and "scratchy high frequencies" their only downfalls?

Apart from not needing a xover, are there any advantages to using piezo tweeters? How is development of piezo's going? Are they getting better? Will they ever reach close to a par with voice coils in tweeter applications?


Piezo's to my ears, sound like crap, pure crap, always did, always will.
No self-respecting manufacturer makes a decent system with them.
Only budget/cheap stuff.
And budget means crap.
 
Piezo's to my ears, sound like crap, pure crap, always did, always will.
No self-respecting manufacturer makes a decent system with them.
Only budget/cheap stuff.
And budget means crap.


Klipsch used 5 piezos in a vertical concave array with the MCM 1900 theater / concert speaker system, and had a crossover designed to work with the piezos.



This piezo unit was called the MTM, pics in this post:



I have a Klipsch MCM 1900 4-way system with a noteworthy history for sale - Garage Sale - The Klipsch Audio Community


I also used to believe ( erroneously ) that piezos were garbage from past experiences with poor implementation or damaged units from excessive high voltage.



Following advice from Dennis Kleitsch, I auditioned a fully functional MCM 1900 system in Indianapolis with the piezo array. I don't have measurements of the system, but I can tell you that in my opinion the HF was very high fidelity, with incredible output.
 
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Klipsch used 5 piezos in a vertical concave array with the MCM 1900 theater / concert speaker system, and had a crossover designed to work with the piezos.
This piezo unit was called the MTM, pics in this post:

I have a Klipsch MCM 1900 4-way system with a noteworthy history for sale - Garage Sale - The Klipsch Audio Community

I also used to believe ( erroneously ) that piezos were garbage from past experiences with poor implementation or damaged units from excessive high voltage.

Following advice from Dennis Kleitsch, I auditioned a fully functional MCM 1900 system in Indianapolis with the piezo array. I don't have measurements of the system, but I can tell you that in my opinion the HF was very high fidelity, with incredible output.


All well and good.....IF you're using them in a large theater, outdoors or partially deaf due to aging.



Horned piezos and horns in general to me are for projection and covering distance - not my idea in an 18 foot living room.
 
My results with quality motorola were superb.

Motorola ksn 1038a.

It has a bad resonance at 4.5khz, but I was using it with 24db LR active crossover at 5khz and up. Turning crossover point down, it got in your face buzzy fast. Think I had a 30ohm resistor in series with it too.

Otherwise, passively, you need to transformer couple it (with the 8ohm tap towards the amp), add a zobel, add a resistor to bring (changing Z) close to the 25w tap (I think), and also notch out a resonance (somewhat).

Freddyi is the now expert and measured super low distortion using ksn 1016 piezo.
You can find many posts by him here and audioasylum.com

I saw djk's piezo array (5 x ksn 1016a Motorola), yes, it was the klipsch 1900 looking one.
 
PIEZO ARE GREAT SOUND MACHINES :MOTOROLA is the best >>experienced !

The quality of a piezo speaker is directly proportional to the size and quality of the piezo element used :ORIGINAL Motorola (now PIEZOSOURCE >>> Piezo Source, Inc. ),Goldwood (https://www.goldwood.com/goldwood/mids-and-tweeters/piezo-tweeters/ )
and MONACOR (MONACOR: Search Results "piezo" ) with the same GOOD QUALITY 22mm. diameter piezo element inside for ALL the models:They are the best brands on the market.

Having tried them personally (and checked the internal quality), what I write is the truth experienced, no prejudices or chatter!

Bigger the piezo element (the active metallized part on the ceramic!) and the precision of the assembly, enormously better the sound (HORN type used is a separate matter !).
ORIGINAL Piezo Motorola are excellent in every aspect and for example, there is no piezo driver on the market bigger and more powerful than the KSN1188A.
Aganin :
Stupidity is to use piezo tweeter (or driver) without proper crossover :Using it, You get exceptional results and the sound played by a piezo becomes of higher quality than a mobile voice coil tweeter !
It is always necessary to investigate, to experience and to try : especially with electronics and physics but unexpected results can be obtained.
In the life , there is a lot to discover !
 

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MONACOR PIEZO are good quality and with BETTER SOUND AND CONSTRUCTION THAN "GRS"brand

Having tested numerous drivers and tweeters piezo in various configurations, with and without crossover ,with or without impedance transformer, I found that :
Using the same HORN, the tweeter piezo branded "MONACOR" model MPT165 is considerably superior in both:In the sound reproduced and constructively than the brand "GRS" model PZ1165 .Although , the diameter of the piezo element is the same (22 mm.)
 

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Who is interested in measurements - on my blog there are Piezo Tweeters with a 12 db crossover. Try google translation because its in german.

Tweeter with 100 ohm in parallel, 027 mfd an 1,36mh, 12 db crossover with measurement.
I covered after the measurement the diaphragm with aluminium foil.

Measurement without crossover (blue)
Measurement with 100 ohm parallel and 0,27mfd capacitor (red line)
Measurement with 100 ohm parallel directly between hot and ground of the tweeter and 0,27 mfd capacitor and 1,36mh in parallel
An externally hosted image should be here but it was not working when we last tested it.


Dragan from Germany
 
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piezo horn

rereading my last mess. leaves me some what unclear. What i'm asking is any one aware of a company state side that deals with piezo's ? Parts express carries GRS,and GOLDWOOD, i'm hoping for another source, hopefully brand new! and of a better build quality- something as close to the MOTOROLA 1140a as posible?:crackup:
 
Could be that dsp power can help to bring resonances down in piezo drivers or make the response better not only in the frequency response but also in the waterfall decay. But I did not try this.

As my use of piezos is only for the indirect sound field their frequency response is not so important.

My piezos have no damping behind the paper diaphragm and have no damping of the piezo itself by some 1mm thick rubber (Motorola piezos had some damping here.)


Maybe you could get some Monacor Piezos from Ebay directly from Germany.

The biggest difference in sound you get from covering paper diphragms with aluminium foil. I do this nearly on all my loudspeaker drivers. This is mainly due to a change in impulse response. Original drivers are poor in this discipline.
 
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