Mods for Community CSX38

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I have 4 of these left over from the band days and occasionally drag em out for some DJ duty. Very rough/shrill high mids I think due to piezo. EQ just barely takes the edge off. Curious if anyone could suggest a cost effective mod to improve their performance. Leaning on a replacing HF driver or maybe not even worth the hassle. Upgrade to a better piezo, or lower end titanium. Any thoughts appreciated.

http://www.google.com/url?sa=t&rct=...PgTjh81RXJ6b20g&bvm=bv.95039771,d.aWw&cad=rja
 
Thanks Sonce. I did not know that about the Community piezo. You also raise a good point about the crossover. I've had the crossover out for jack repair and from what I could tell it was pretty robust but I am completely a newbie to XO construction. Happy to post a pic if it helps someone rule that out as a problem. Right now, thinking of trying a Pyle PDS182 for $20 or maybe from what your saying I'll need to get something even nicer to edge out the PZT. My DIY experience is primarily subs like the Keystone.
 
New driver (and horn!) needs totally new high-pass filter in the crossover. Don't even start thinking about serious crossover designing if you don't have calibrated mike, measurements software (REW, ARTA), crossover design software and good knowledge about crossovers and loudspeakers.
But if you want to have a fun playing with crossover components values, here is a crossover I designed for a cheap chinese compression driver (similar to Pyle PDS182) fitted to a big horn in the plastic 12" two-way loudspeaker. It is a second-order high-pass filter, consisting of 2.7 microF capacitor and 0.39 mH inductor. In front of capacitor, serially with it, put 1 or 2.2 ohm resistor (20W) and a light bulb for driver protection.
If high frequencies are too loud, use smaller capacitor (2.2 or 1.8 microF) and bigger resistor (3.3 ohm). If it is not loud enough, use bigger capacitor (3.3 microF).
 
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Thanks again Sonce. Am I correct that I need a new high pass because there was not one used due to piezo? Was wondering about that. There is the light bulb fuse thingy in there already. Replaced some of these a few years ago. Since your knowledgeable, mind if I ask you to critique the XO if I post a pic?
 
Am I correct that I need a new high pass because there was not one used due to piezo?
Yes, compression driver need different high-pass filter than piezo. Piezo driver need only resistor serially with it, or, as you can see from the link provided by PeteMcK, a more sophisticated arrangement to make a first-order high pass filter.
Photo of the CSX-38 crossover would be useful, together with the values of the capacitors.
 
Thanks for playing along Pete and Sonce. Agreed that a pic is a good idea. I will shoot one and get the data on the components and report back. I've got a decent knowledge of electronics but one thing that eludes me with crossovers is power rating of the components. So that 22ohm resistor in the frugal-phile page needs to be how many watts? Probably an Ohms law thing.
 
Here goes. I can remove bracket if need be as is dual sided pcb. Writing on inductor is covered with hot glue, but appears to be "220", but I can also remove if need be.
 

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Interesting, it seems that there is no low-pass filter for the 15" midbass, only overcurrent protection with light bulbs plus automatic circuit breaker. Unusually, high-pass for the piezo driver seems to be second-order (12dB per octave) with 5 microF capacitor and the inductor (parallel to 20ohm/5W resistor), something I didn't saw before. Because of steeper roll-off, 5W is enough power rating for the 20ohm resistor. 50ohm/10W resistor should be parallel to the light bulb, completing tweeter protection.
Can you draw the complete schematic please, because inductor has 3 instead of 2 leads? Something interesting is going there...

You can attenuate shrill high mids with 3.3 microF capacitor instead of the original 5 microF.
 
Well, I was almost right. High-pass filter is a first order, and three-legged inductor actually is a step-up transformer ("booster"), so piezo driver has higher sensitivity - to match midbass.
Replacing 5 microF with 3.3 microF/250V will ameliorate shrill high mids. If that is not enough, put 22ohm/10W resistor in series with the piezo (after the step-up transformer).
 
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