Hey all new to building and very excited about it all, the one thing thats really hanging me up is looking at crossover schematics and figuring out how to build them. I want to make a simple 2 way with a seas crossover, Seas has the schematic on the website which I have attached here, and ive spent hours staring at it and it hurts my brain to understand whats going on. I figured out all the parts i need, but wiring them all together i just don't understand. It seems like the L1 0.120mH inductor gets shared by the woofer and tweater, is there a reason for that? cost savings? is it possible to build this crossover in 2 discreet lines basically one group of parts for the woofer and one for the tweeter or do they need to do all this crazy sharing? Apologies if this is a really dumb question but i am stuck and i've learned so much reading all your posts here i was hoping someone could put this into dummy terms for someone starting just like me.
L1 and L2 are separate devices. Is that what you meant? ..or maybe you were asking whether L1 interacts with the woofer, and no it doesn't.
Ok thank you so much. So every component for each driver is completely separated from each other ? It’s the weird forks that break off that I think confuses me.
This is a rather ordinary crossover but you may not be familiar with the way it is drawn.
3rd order HPF (18dB/oct)
2nd order LPF (12dB/oct)
You can very well separate this with biwire/biamp. Just disconnect (4).
I think you might be confused by the arrow at L1 pointing at L2 and the fact that they share almost same value with a factor of 10. But they are not linked. The arrows is ground (or minus pole on the terminals). All the ground arrows shall be joined at minus terminal. Or if it’s a biwire terminal just disconnect 4 and connect upper arrows to HF terminal minus and lower arrows to LF terminal minus. Hope it helps. Some more notes. R1/R2 are used to lower the tweeter a dB or two, it’s called LPAD. L3 and R3 are used to flatten some cone breakup resonances above the crossover point to even out the midrange response.
3rd order HPF (18dB/oct)
2nd order LPF (12dB/oct)
You can very well separate this with biwire/biamp. Just disconnect (4).
I think you might be confused by the arrow at L1 pointing at L2 and the fact that they share almost same value with a factor of 10. But they are not linked. The arrows is ground (or minus pole on the terminals). All the ground arrows shall be joined at minus terminal. Or if it’s a biwire terminal just disconnect 4 and connect upper arrows to HF terminal minus and lower arrows to LF terminal minus. Hope it helps. Some more notes. R1/R2 are used to lower the tweeter a dB or two, it’s called LPAD. L3 and R3 are used to flatten some cone breakup resonances above the crossover point to even out the midrange response.
Every component? No, they do interact. Node 4 is a special point when used with a certain kind of amplifier. For the time being you can consider the circuit split at that point.
Amazing thank you. This helps a lot . I’ll draw this out with pictures and wires as a test for myself and post here to make sure I get it right. You guys are all awesome THANK YOU
I would like to add here that the Excel coaxial is a very expensive driver that's not the easiest to use. You're going to need a well designed crossover for it to sound any good.
It'll be okay I'm sure. I didn't realise this was done by SEAS. I should have read all of your thread more closely.
The «problem» with this driver and most Seas excel bass drivers is the cone breakup at 6-7kHz due to the vert stiff magnesium/aluminium cone. But this is delt with in L3/R3 so it should be fine. Another issue with coax in general is phase but I believe this is fixed using uneven order 18/12. Interested to see final results. Have considered this driver for a long time myself for a near field monitor.