Binary L/C substitution unit for crossover evaluation

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Inductor Coil Crosstalk Basics and Measurements.
Inductor Coil Crosstalk Basics | Audioholics

Here are some mounting changes to reduce cross coupling.
The 8 mH inductor on the left is not attached to the main board and can be located away form the others as required.
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You could tap off inductors, one for tenths, another for units, and another
for tens. With easy to dial in rotary switches. Seems your setup there does
save on caps and resistors. The decade boxes do also use some tricks to save
on the number of parts.

I see what you are trying to do there, are those switches on the front panel?
That is a lot of work for the number of components you are getting.

I simulate in Xsim, then build it and if there is a value I want to adjust while
measuring or listening I have decade boxes, bought on ebay, where I've replace
the caps and resistors with new parts. I have 0-10 uF, and 0-1uF dials, I can
add 10uF or any amount more with caps on dual banana plugs.
Resistor boxes are 0-10 and 0-1, so units and tenths, I should probably add a
tens dial but I just add it on externally when needed.
These are what I buy fairly inexpensively:
http://www.radioblvd.com/TestGear/CDEdecadeboxes.jpg

Don't know why I didn't look for 3 dial boxes - I should have.
 
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I see what you are trying to do there, are those switches on the front panel?
That is a lot of work for the number of components you are getting.

All the dots on the front panel represent switch locations. I want a compact detected unit for crossover testing that has the necessary values that can be easily changed during testing.

Wiring for 8 components has 8 wires, 1 common, 1 in and 1 out. Which is 11 wires for 165 different values.

First and second order crossovers can be configured using the IN/OUT/GND center off switches at the right. The Banana jacks marked W, on the schematic, allow third order crossovers to be configured using jumpers on the back panel.

Thank you
 
I notice that quite a few people are telling you that this is not going to work and that
is certainly true for poorly chosen drivers that need a lot of correction and/or do not
match up well. Then a very complex crossover is required.
The most common crossover in good sounding, intelligently designed systems, is
roughly 2nd order combining with the driver response for 4th order electro-acoustical.
Some excellent systems just off the top of my head:
PSB Stratus Mini (also uses a series RLC)
Signet SL280
Both of the above had detailed reviews in the old Speaker Builder magazine with crossover
schematics - anyone know of these online? They'd be good for a tutorial.
Here is just an example chosen because it is simple and available online, it uses 3 inductor
and 3 caps so you'll need some extra values around or a few decade boxes to help what
you have there:
My RS180 MTM Design - Techtalk Speaker Building, Audio, Video Discussion Forum

This thread with the Minimus-7 mod gives another example of what I'm talking about,
2 caps, 2 inductors and 2 resistors, R3 is not needed it just flattens the input impedance:
Minimus 7 PZ-2.2 Mod DIY Circuit Board by Pete Basel | Audiokarma Home Audio Stereo Discussion Forums

Sure, many designs are overly complex to correct for driver issues, but I suggest choosing
better drivers.
Your not going to do a 3-way, with all variable parts but perhaps with some fixed and
some decade boxes. The outstanding PSB Stratus Gold employs a good simple 3-way topology:
http://www.diyaudio.com/forums/multi-way/230929-psb-stratus-gold-x-over-help.html#post3393485
 
Mutual Inductance coupling can be minimized when the inductor is mounted in a steel enclosure. The field travels in the walls of the box and has limited penetration. The box cover can be used for mounting power resistors and provides limited heat sinking. The inductance increased less than 4% due to the steel box. The total cost for 4 boxes and covers is $14.

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