Crossover design question

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Get rid of the unit that performs inadequate for a desired xo point. I understand this is a 12" full range unit, so I would plan to cross over at about 2-3 kHz, if possible. Is this horn loaded unit any good for such a task, I have no idea without seeing measurements. Any normal 1" compression driver on a horn should be good for crossing at 2.5-3kHz and it would probably have enough of the high frequencies to not need a super tweeter. Is this unit of yours like that?
Parallel crossovers are my choice of preference, and with a competently designed filter, with smoothing impedance conjugate filters, present a friendly load to any tube amp. This can't be done properly without measurement equipment of some sort. If there were manufacturer graphs, we could work out a good guesstimate.
 
Get rid of the unit that performs inadequate for a desired xo point. I understand this is a 12" full range unit, so I would plan to cross over at about 2-3 kHz, if possible. Is this horn loaded unit any good for such a task, I have no idea without seeing measurements. Any normal 1" compression driver on a horn should be good for crossing at 2.5-3kHz and it would probably have enough of the high frequencies to not need a super tweeter. Is this unit of yours like that?
Parallel crossovers are my choice of preference, and with a competently designed filter, with smoothing impedance conjugate filters, present a friendly load to any tube amp. This can't be done properly without measurement equipment of some sort. If there were manufacturer graphs, we could work out a good guesstimate.


the full range 12" driver goes to 16000hz
the horn goes to 12,000hz
 
Blake, can you do me a huge favor please. could you redesign another crossover taking into account these things below

tweeter, is a ribbon tweeter 4ohm im sure it can go beyond 20,000hz
the horn is a 20ohm, and frequencies are 630 Hz - 12500 Hz
and the woofer is actually a full range driver 40Hz-16000Hz 8ohm

And i would like to use all 3 drivers just dont know where to cross all these drivers at.
 
You can buy a measurement microphone online. Search on Amazon, eBay or dozens of smaller sites. The ECM8000 is a good mic.

A little while ago and bought a MiniDSP UMIK-1 (calibrated USB microphone) and downloaded REW. If you don't mind the expense and extra bulk, a stand alone TRS plug measurement microphone and dual channel audio interface is the superior option, as it allows you to use two mics for power response measurements referenced against the on-axis response and phase. The stand alone audio interfaces are also superior to a USB mic if you do any audio recording.

I later built the impedance measurement jig using a double ended 3.5mm stereo cord (for laptop headphone and mic jacks) and a 100 Ohm calibration resistor as per the diagram in REW's "help" section. It worked out great.
 
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Blake, can you do me a huge favor please. could you redesign another crossover taking into account these things below

tweeter, is a ribbon tweeter 4ohm im sure it can go beyond 20,000hz
the horn is a 20ohm, and frequencies are 630 Hz - 12500 Hz
and the woofer is actually a full range driver 40Hz-16000Hz 8ohm

And i would like to use all 3 drivers just dont know where to cross all these drivers at.

It's not that simple.

To design something other than an example I would need detailed information about your specific drivers. That will require actually having them here and measuring them. I would need to know impedance vs frequency and output vs frequency, at least.

This is why I recommended XSim and REW... and you may need even more gear to get this one going. For example you may need a DATS unit to do the actual measurements.

And, of course, there's quite a learning curve that goes along with all this... I've been in electronics for over 30 years and what you want is right on the edge of my skillset.

I'm thinking the takeaway here is that you can't just stack a bunch of random stuff up together and expect it to work.
 
No I just think it sounds better, the horn Adda something that the full range driver can't do..then when I added the ribbon tweeter it just sings!! String instruments just sparkle in the air, I love the way they all sound together, that's why.

Have you tried the ribbon tweeter alone with the full range? It will be that small tweeter that's giving you that sparkle.

From what you've told me the horn cuts off lower than the full range and is of a much higher impedance, so it's unlikely it's contributing all that much to the overall balance of sound.

You could likely get as good or better results by putting the ribbon tweeter on a nice wooden baffle then wiring it up like the thumbnail along with your full range speaker.

You can get all the parts rather cheaply from Parts Express.
This is the L-PAD... Speaker L-Pad Attenuator 100W Mono 1" Shaft 8 Ohm

(Sorry about the back to back posts, guys.)
 

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Also All About Circuits for the theory behind the individual components. It is beyond helpful to know what a capacitor does, what a coil does, and so on.

Capsa cut of low freq, and only let high freq pass correct? And coils opposite right? I was looking at your diagram for the load and ribbon tweeter, since the load is 8ohm amo will see it as 8ohm and not 4 correct? But the since I will connect it parallel with Full range 8ohm driver it will give me a total of 4 ohm, correct?
 
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I think we should get technical..

100Hz is a woofer frequency, and at 100Hz your 2uF capacitor is blocking for your tweeter, like you said. Its impedance is high at 100Hz and its impedance is low at high frequencies so the treble is not blocked to the tweeter.

At 100Hz the capacitor impedance is 800 ohms. It is in series with the tweeter, so add that which makes it 804 ohms (*).

Now, the current from the amp can flow two ways, through the 8 ohm woofer and through the 804 ohm tweeter with capacitor. Do you think the tweeter will get much interest?
 
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