OK to wire 2 inductors in series?

[Pat S]

I am adding Fountek ribbons to my 1.6 Maggies. At first I wanted to crossover at about 5000Hz but due to my lack of knowledge I am shooting for the 8000Hz area, thinking I will do less damage there. They don't make these little foil inductors in too many sizes so I was wondering if it sounds bad when you wire 2 foil inductors in series to get closer to the textbook values?

Thanks

[li_gangyi]

in theory it would work...but u have to make sure the magnetic fields DO NOT interact with one another...and u also have higher resistance...

[rabbitz]

Make sure you place the 2 inductors at right angles to each other (1 flat and the other standing up) and at least 75mm apart to avoid magnetic coupling.

You might be able to wind on additional turns so you have only 1 inductor or get a larger size and unwind some turns.

With crossing over at 8000Hz means that the inductors are going to have small values so the DCR isn't going too be high if you run 2 in series. Just aim for the DCR is less than 5% of the driver DCR. So if your driver DCR is say 4ohm then keep the inductor total DCR less than 0.2ohm.

Hope this helps.

Cheers

[markp]

Two inductors in series is fine but you would be better off buying a larger coil and unwinding it to the value you need.

[Pat S]

Thanks for the replies. I didn't think of unwinding the coil of a larger inductor. I can probably find out how much form the retail outlet.

I ordered two speaker building books so I hope to keep the questions to a minimum.

Thanks to everyone who contributes to this forum.

[budwiser]

You can also call alphcore and have them make one for you. There price is based on the cost of the next closest inductorer to the value you want. Look at there web site.


Pete

[rabbitz]

There's a good little inductor calculator here:

http://members.optusnet.com.au/~audiosoft/inductor.exe

Can help in working out how many turns to remove and is quite accurate as have checked with a LCR meter. Won't help on foil inductors though.

[Pat S]

Thanks for the help guys, this is a great site.

I ordered two Weems speaker building books from the library and bought a 1985 version of High Performance Loudspeakers by Martin Colloms off the internet today for $10, $13 delivered to the door. I hope it isn't missing too many pages.