Can anyone help understand this two-way crossover?

[Heat-Sinks-R-Cool]

I traced this crossover and created the attached schematic. It's from an outdoor two-way 2 woofer/1 Tweeter. Woofers are 5 1/4" 8 ohm aluminum cone and a 1" dome tweeter. I can sort of understand the low pass filter (Woofer 1 and 2). I dont know the values of the Inductors, but L1 has a ferrite core and L2 is an air core. Cap values are measured values. Is the low pass a 3rd order filter? I am totally confused on how to analyze this particular crossover. It's not like any I've seen, but have not seen too many , so maybe it's just my rookie status...LOL

 

[Gepetto]

I traced this crossover and created the attached schematic. It's from an outdoor two-way 2 woofer/1 Tweeter. Woofers are 5 1/4" 8 ohm aluminum cone and a 1" dome tweeter. I can sort of understand the low pass filter (Woofer 1 and 2). I dont know the values of the Inductors, but L1 has a ferrite core and L2 is an air core. Cap values are measured values. Is the low pass a 3rd order filter? I am totally confused on how to analyze this particular crossover. It's not like any I've seen, but have not seen too many , so maybe it's just my rookie status...LOL View attachment 68582

Could be you incorrectly transcribed the schematic from the actual crossover. I would be inclined to go back and check it again.

 

[Heat-Sinks-R-Cool]

Found one error in the transcription... removed R2 to C2 connection... still pretty stymied by the tweeter filter.

 

[Gepetto]

Found one error in the transcription... removed R2 to C2 connection... still pretty stymied by the tweeter filter. View attachment 68585

You are getting there, now it is starting to make sense. The tweeter is a simple high pass filter, The L/R (L2 and R2) squash any low frequency to the tweeter. The inductor opens up at high frequency, leaving the high pass combination of C1/R3 going to the tweeter. Makes perfect sense now.

 

[Heat-Sinks-R-Cool]

So the L2 R2 is another low pass (squash) to further attenuate any low frequency C1 passes. Would this be considered 2nd order for the tweeter and create a 12dB/octave response?

 

[Gepetto]

Yes a low Q 2nd order high pass

 

[Heat-Sinks-R-Cool]

Thanks for your help on this!

 

[Gepetto]

Thanks for your help on this!

If you drew the tweeter schematic from left to right instead of the way you did, it would likely pop more for you that it was a 2 pole C-L filter...

 

[mlucitt]

Joe,
You are pretty good with crossovers. Is this a 3 pole RCCCCCCCCLLLLLLLLL?

 

[Gepetto]

Joe,
You are pretty good with crossovers. Is this a 3 pole RCCCCCCCCLLLLLLLLL?
View attachment 68617

That is a classic damping factor killer Mark...

 

[George S.]

Makes a good case for a active crossover and multiple amps, eh?

 

[Gepetto]

Makes a good case for a active crossover and multiple amps, eh?

You do not waste power into a crossover network that consumes power, that is for sure. And there are some crazy, power sucking crossovers out there. But what are you going to do as a speaker manufacturer to suit the general market. With active, you have to be careful about the filtering creating lots of phase distortion. I prefer 6dB per octave crossovers, whether active or passive. Phase distortion is very audible.

 

[J!m]

Let’s find some pictures of Thiel crossovers…

More complex than the space shuttle OS.

 

[Gepetto]

When you hear about impedance dips in speakers, very often it is the crossover design and not the drivers.

 

[mlucitt]

I prefer 6dB per octave crossovers, whether active or passive. Phase distortion is very audible.

Give me a Linkwitz-Riley 2-Way 6th Order (cascaded Butterworth filters) Crossover any day.
https://europe-audio.com/crossover_calc.asp?id=15

 

[J!m]

I prefer the sound of first order crossovers. Thiel and Vandersteen. Not sure whom else.

 

[laatsch55]

Give me a 92db cliff to drive off anyday..

 

[George S.]

Thought the Linkwitz-Riley 48 dB filters were steep. 92 dB? Sheesh.
Going to play around some more with this, but works well for German electronic synthesizer music.

 

[laatsch55]

Yep, that's what Al Klappenberger's "EXTREME SLOPE" crossovers are for the K's...

 

[George S.]

Truth is, I understand so little about this stuff that I need a graphic representation to maybe halfway understand a little better. I find electronics to be extremely perplexing. It's nice to be able to see a representation of what's happening.