ZD5 Crossover

[roscoe84]

Hello all,

I'm new here and I'm looking for some help with the crossover for Zaph's ZD5 speaker. I've only ever built parallel networks and when I look at Zaph's schematic I'm not sure where I should bring in the negative side. Hope someone here can be of assistance. Thanks in advance for any help.

EK

[Jay_WJ]

Your drawing is correct. A difficult part of this schematic is the ladder delay network. Attached is my drawing of the same ZD5 crossover. If you can see this is the same as Zaph's drawing, it means that you correctly understood the schematic.

[roscoe84]

I should have probably tried to explain my sketch in the first post [apologies for my art work] and I have drawn Zaph's crossover for the ZD5 as I would make it. I'm keen to know if the negative side of my schematic is correct or not? The rest of the crossover is identical to Zaph's.

Thanks all again.

EK

[roscoe84]

No confusion Jay and thanks very much for that, it was exactly what I was looking for.

EK

[roscoe84]

Jay,

Just one question, in your drawing what has happened to the resistor R9? Otherwise, I'm following it just fine.

EK

[Jay_WJ]

R5, R9, and R15 in Zaph's drawing are not real resistors. They are DC resistance of corresponding coils. Also note that R12 in my drawing is 4.0 ohms rather than 4.7 ohms in Zaph's. The reason is that a 19/20 gauge 1.0 mH coil for L11 will have DCR of 0.5 to 0.7 ohm and using a 4 ohm resistor for R12 will result in total series 4.7 ohms as specified by Zaph.

[roscoe84]

Jay,

Thanks mate, all clear.

EK

[valleyman]

I built my ZD5 crossover yesterday and have just posted a pic of my layout here:

ZD5 Damping (+crossover pic)

Hope it can be of some help

[KAR]

Originally Posted by Jay_WJ

Your drawing is correct. A difficult part of this schematic is the ladder delay network. Attached is my drawing of the same ZD5 crossover. If you can see this is the same as Zaph's drawing, it means that you correctly understood the schematic.

How critical is the resistance of L11 and R12? The spec calls for 4.7 ohms but mine is at 4.5-4.6 according to my ohm meter. I used the 3.9 ohm mundorf. Should I try harder to get this to 4.7?