2-way crossover, need feedback!

[signalcorps]

Hi!
Im happy to share with you this 2way project

Regarding
L1 ... looks too small for a woofer? cant find a aircore inductor on 0.0039mH
D1 Cap..... also the value seems odd
sure must be something really wrong or truly right.

Need some light from you experienced folks

All the best Everyone

 

[stv]

Check the impedance, L1 and C1 don't have much influence on the driver output, they just lower the impedance, practically mute your whole speaker and kill your amp.
Also, remove the parallel resistor from your woofer network.
Did you consider the baffle influence?
Can your tweeter cope with such a low x-over frequency?

I suggest you start with proven example of a 2way speaker and study it in depth!

 

[analogkid455]

Your cap is 8200uF that is why your coil is .0039 mH.

 

[signalcorps]

L1 and C1 don't have much influence on the driver output, they just lower the impedance, practically mute your whole speaker and kill your amp.

this situation is theoretical or its happening with the circuit right now?

remove the parallel resistor from your woofer network

could you help me understand its role in this situation? in the case of the simulation it is helping to tame 2k range area. but i don't understand the reason it is a bad choice (noob here)

Did you consider the baffle influence?

no Baffle considered yet

Can your tweeter cope with such a low x-over frequency?

from the box designer perspective, he says its fine



as soon i mess with more usual values on L1 and C1 the slope starts to become a messy ugly thing
any explanation on any issue is really welcome

All the best!

 

[analogkid455]

Try .39mH on L1 and a 17uF at C1.

 

[stv]

as soon i mess with more usual values on L1 and C1 the slope starts to become a messy ugly

Because as it is now they do not have any effect except lowering the impedance to almost zero.
Just delete C1 and short L1 and check the result.

no Baffle considered yet

You need to do that. Do some research on baffle step.

could you help me understand its role in this situation?

You drew the schematic, so you should know what you did ...

But in short: the parallel resistor just eats up half of the woofer energy and maybe equalizes the woofer impedance (but it's a terrible method, you would need a 50 or higher wattage resistor).
You need to study some basics - just check some existing projects ... lots of them here on this forum.

 

[GeoffMillar]

Which drivers are you using please - there may be an existing project which uses them or similar and that will give you a head start

Geoff

 

[signalcorps]

Which drivers are you using please - there may be an existing project which uses them or similar and that will give you a head start

Woofers Eminence Beta-12CX
Tweeters ASD1001S

 

[analogkid455]

That tweeter won't like crossing over at 1500 hz. The resonance frquency is 1200 hz. The lowest I would go is 2400 hz. I would suggest the D220Ti.

 

[indianajo]

Beta-12cx has a rather tame cone breakup at 2 khz, a 3 db rise at 1 khz, and a 6 db rise at 2 khz. I would try a 6 db/octave crossover to reduce those a little from 800 hz up. A single 1.5 to 1.7 mH coil series the woofer should do it.

 

[A4eaudio]

Your offsets are incorrect. You have a z-offset but no y-offset, but it should be the other way around. You should have a negative y-offset on the woofer, assuming it is below the tweeter.

 

[Dave Bullet]

Ditch L1 and C1 - they are bogus value elements. Your lead series inductor will be in the range of 0.8mH - 1.5mH for a 4 ohm nominal woofer or 1.6mH - 3mH for an 8 ohm nominal woofer, depending on baffle step. You seem to have this correctly handled, so I'm thinking the 1mH value you have is about right:

 

[mattstat]

z-offset but no y-offset

Beta 12CX is a co-ax.

 

[A4eaudio]

Thanks Matt, I wondered about that but didn't take the time to Google it.

 

[Dave Bullet]

Your offsets are incorrect. You have a z-offset but no y-offset, but it should be the other way around. You should have a negative y-offset on the woofer, assuming it is below the tweeter.

Assuming this is a 2 way design with separate drivers (i.e. TM)

Well - the Z offset being positive will push the woofer voice coil behind the tweeter and that is correct.
I believe a negative Y locates the woofer down / below the tweeter (unless you 've applied a Baffle diffraction sim to allow for Y rolloff already -but unlikely)
So in this case the poster is likely to need both Positive Z and negative Y