"One Driver - Two Tweeters"
A few years ago, when I didn't really know what I was doing, I decided to build a replica of a DJ monitor I had owned in my youth.
The plans called for 150 litre enclosure housing a 15" woofer and two KSN 1025's (Yeah, I know)
So I choose an Eminence Delta-15LF-C
https://www.ltt-versand.de/en/sound...eminence-delta-15-lfc-15-speaker-500-w-4-ohms
topping out at 3200Hz and a pair of Monacor MPT-025's rolling in at 3000Hz
https://www.ltt-versand.de/en/sound...-tweeters/20312/monacor-mpt-025-piezo-tweeter
Seemed like a sensible choice at the time.
Now, I have a few questions but I will start with this one.
When it came to wiring this set-up, I had no diagram and the local PA "guru" of the group advised me to
"wire the tweeters in series.... Parallel to the cone"
So I did.... But ever since then every configuration of one driver and two tweeters I have seen are not wired this way.
Is my system wired correctly.....?
I am currently re-building this box but obviously because of the cut-outs I cannot really change the tweeters.
I am reading lots of conflicting information online about resistor values and crossover circuits for piezos but again,
all for just one driver and one tweeter.
I would like to quieten these screamers down a few dB's..... Would anyone have the proper schematic or some sound advice for this
seemingly unusual configuration……?
A few years ago, when I didn't really know what I was doing, I decided to build a replica of a DJ monitor I had owned in my youth.
The plans called for 150 litre enclosure housing a 15" woofer and two KSN 1025's (Yeah, I know)
So I choose an Eminence Delta-15LF-C
https://www.ltt-versand.de/en/sound...eminence-delta-15-lfc-15-speaker-500-w-4-ohms
topping out at 3200Hz and a pair of Monacor MPT-025's rolling in at 3000Hz
https://www.ltt-versand.de/en/sound...-tweeters/20312/monacor-mpt-025-piezo-tweeter
Seemed like a sensible choice at the time.
Now, I have a few questions but I will start with this one.
When it came to wiring this set-up, I had no diagram and the local PA "guru" of the group advised me to
"wire the tweeters in series.... Parallel to the cone"
So I did.... But ever since then every configuration of one driver and two tweeters I have seen are not wired this way.
Is my system wired correctly.....?
I am currently re-building this box but obviously because of the cut-outs I cannot really change the tweeters.
I am reading lots of conflicting information online about resistor values and crossover circuits for piezos but again,
all for just one driver and one tweeter.
I would like to quieten these screamers down a few dB's..... Would anyone have the proper schematic or some sound advice for this
seemingly unusual configuration……?
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It's OK to put piezo tweeters in parallel as per the recommendations here: https://www.frugal-phile.com/piezo-XO.html
The link also describes how to attenuate the piezos.
The link also describes how to attenuate the piezos.
Components for your Monacor piezos which extend down to 3 kHz:
Looking from the amp, first a 2.2 uF series crossover cap, then the 22 ohm shunt from hot to ground, then a series cap of about 0.15 uF for 6 dB attenuation.
Looking from the amp, first a 2.2 uF series crossover cap, then the 22 ohm shunt from hot to ground, then a series cap of about 0.15 uF for 6 dB attenuation.
Hang on, I am sorry but I am still trying to grasp this, ugh!
My tweeters are in series..... Parallel to the cone.
So you are saying my tweeters should be both parallel.... And when you say after the amp.... Do you mean after the cone also, as in the components are between the driver and the two tweeters.
My tweeters are in series..... Parallel to the cone.
So you are saying my tweeters should be both parallel.... And when you say after the amp.... Do you mean after the cone also, as in the components are between the driver and the two tweeters.
You appear to have understood correctly.
For best results the piezos should be in parallel as described in the link.
The combination shown in my image should be connected directly across the bass speaker's terminals.
Might as well just draw this...... Obviously there's an input missing..... From the bass speaker terminals ——>
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There's not a large proportion of the total energy delivered to the speaker system in the high frequencies passed by the 2.2 uF capacitor.
To err on the safe side, I'd use as a minimum a 10 W ceramic wirewound resistor.
To err on the safe side, I'd use as a minimum a 10 W ceramic wirewound resistor.
Thank you.
I have just realised that capacitors have differing voltage values also.
50V looks fairly normal for a 2.2uF cap and 100V for a 0.15uF
I will likely go with those unless somebody says not to.
I have just realised that capacitors have differing voltage values also.
50V looks fairly normal for a 2.2uF cap and 100V for a 0.15uF
I will likely go with those unless somebody says not to.
Higher than 50 V would give you a safety net for your application.
Like a 2.2 uF, 250 V Monacor film cap: https://www.ebay.co.uk/itm/256229717069?hash=item3ba87b344d:g:eGsAAOSw5l1lDr5B&amdata=enc:AQAIAAAA0EUQA3KiMMUNkAYnl7mO7mxSe48aAMQeHRIVVIowgEzLhlSDommjM8QM+m1/8f/WGSVXuB9l27efvc/cvZZ8FR+XjF/Fbj+XwaO5lGn7IgsYdwaBsP53Mxc1V0WGvi1LoJYYvF4+rNzX1GKoVa+DERcndrJCCVP4cG5K9YTkB5zel4Yc8YCX/dwFN4d0XrEoYXuIqERmLfV+WeEL/maerSdnLF8HigUf4wYLd+jrph96C3Z3JdG0d337uWB2HBkI+W7AnxcFoashQG+oDVD/BAI=|tkp:Bk9SR7Ko2N6cYw
Make sure the 0.15 uF cap is also a film cap like this: https://www.ebay.co.uk/itm/314739816137?hash=item4947f476c9:g:KygAAOSw9BBkw8CU&amdata=enc:AQAIAAAA8KQMh4XzEg0Zk5v1zUqGEz5nxMKKnAAj3xzLOn/LTfkNxOQ8L+steFxSzK6Ug+Iq4n1L10jsY97Cw4hyCN1vS0mzySZoAxQgXxtLpsHx5fqH2okb29t99yA1uzwlOW8rmHPcIpSA/R+RhuzQSOkRkHhQ8oG8b13SUgznJc3o+Jt4Xsnid9v+wo3L6Q+JYmmlT2n+P+ddwM5W6Rt7IjAWBSoq+eArg76zxlR/IYtJ6iyl2mY7Hq9Y+5Sq3k3v+uhanQ8p+N3OJUTQjO34SGW92gX+1m2t3yowR/rBWwNHYIxDFCf7e8Lof8Jf0umsz/qRiQ==|tkp:Bk9SR_aOhN6cYw
You may find similar, but less expensive alternatives to that one.
However, do not choose an X2 'safety' capacitor as seen elsewhere on ebay.
Like a 2.2 uF, 250 V Monacor film cap: https://www.ebay.co.uk/itm/256229717069?hash=item3ba87b344d:g:eGsAAOSw5l1lDr5B&amdata=enc:AQAIAAAA0EUQA3KiMMUNkAYnl7mO7mxSe48aAMQeHRIVVIowgEzLhlSDommjM8QM+m1/8f/WGSVXuB9l27efvc/cvZZ8FR+XjF/Fbj+XwaO5lGn7IgsYdwaBsP53Mxc1V0WGvi1LoJYYvF4+rNzX1GKoVa+DERcndrJCCVP4cG5K9YTkB5zel4Yc8YCX/dwFN4d0XrEoYXuIqERmLfV+WeEL/maerSdnLF8HigUf4wYLd+jrph96C3Z3JdG0d337uWB2HBkI+W7AnxcFoashQG+oDVD/BAI=|tkp:Bk9SR7Ko2N6cYw
Make sure the 0.15 uF cap is also a film cap like this: https://www.ebay.co.uk/itm/314739816137?hash=item4947f476c9:g:KygAAOSw9BBkw8CU&amdata=enc:AQAIAAAA8KQMh4XzEg0Zk5v1zUqGEz5nxMKKnAAj3xzLOn/LTfkNxOQ8L+steFxSzK6Ug+Iq4n1L10jsY97Cw4hyCN1vS0mzySZoAxQgXxtLpsHx5fqH2okb29t99yA1uzwlOW8rmHPcIpSA/R+RhuzQSOkRkHhQ8oG8b13SUgznJc3o+Jt4Xsnid9v+wo3L6Q+JYmmlT2n+P+ddwM5W6Rt7IjAWBSoq+eArg76zxlR/IYtJ6iyl2mY7Hq9Y+5Sq3k3v+uhanQ8p+N3OJUTQjO34SGW92gX+1m2t3yowR/rBWwNHYIxDFCf7e8Lof8Jf0umsz/qRiQ==|tkp:Bk9SR_aOhN6cYw
You may find similar, but less expensive alternatives to that one.
However, do not choose an X2 'safety' capacitor as seen elsewhere on ebay.
Thank you again..... Just ordered two of these --->
MONACOR MKPA-22 MKP film capacitor, 2.2 µF, 250 V
MONACOR LSR-220/20 High-power cement resistor, 22 O, 20 W
and a random
from Amazon
MONACOR MKPA-22 MKP film capacitor, 2.2 µF, 250 V
MONACOR LSR-220/20 High-power cement resistor, 22 O, 20 W
and a random
Capacitors - Film Capacitors - CAP FILM PP 0.15UF 630V RAD
from Amazon
I see from the pdf that reducing the value of the 0.15 uF cap will increase the attenuation, should that be found to be necessary.
For example you could wire two 0.15 uF caps in series to get 0.075 uF and around twice the attenuation.
For example you could wire two 0.15 uF caps in series to get 0.075 uF and around twice the attenuation.
"Most piezo elements run in the 0.1 to 0.26 uF range, so a cap of the same value as the piezo element will attenuate it 6 dB."
https://www.frugal-phile.com/piezo-XO.html
6dB sounds about right.
I've just measured my own tweeters with an LCR meter (nothing connected), and the left one reads 0.171uF. Mr. Right is telling me 0.186uF
https://www.frugal-phile.com/piezo-XO.html
6dB sounds about right.
I've just measured my own tweeters with an LCR meter (nothing connected), and the left one reads 0.171uF. Mr. Right is telling me 0.186uF
Damn, just over the edit deadline.
I connected the two of the tweeters to each other, in both parallel and series, and measured again.
Both tweeters had a COMBINED measured capacitance of 0.357uF each way.
I connected the two of the tweeters to each other, in both parallel and series, and measured again.
Both tweeters had a COMBINED measured capacitance of 0.357uF each way.
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@AllenB
Series connection is also possible, but I decided to stick to parallel as featured in my link in order to avoid any possible complications.
The pdf supplied by Databass compares parallel and series connection in terms of sensitivity and spl, but why complcate matters when we have a working solution?
Series connection is also possible, but I decided to stick to parallel as featured in my link in order to avoid any possible complications.
The pdf supplied by Databass compares parallel and series connection in terms of sensitivity and spl, but why complcate matters when we have a working solution?