The Jantzen crossover parts I've been waiting almost a month for finally came in from Europe today, and what do you know, ALL of my non-ferrite core inductor coils are cracked on one side somehow (I say somehow because it couldn't have happed during shipping with the way everything was packaged)
They all have a crack like this:
Is this going to make a big difference in sound, or is it not a big deal? If it's a trivial thing I'd like to just go ahead and make these speakers already (been waiting a while for this stuff to come..) but of course I can't just start soldering things together if the sound will be affected. Is this just a visual thing, or should I get in touch with EuropeAudio.com and sit out another month while they sluggishly send me some replacements?
Thanks for the help
They all have a crack like this:
Is this going to make a big difference in sound, or is it not a big deal? If it's a trivial thing I'd like to just go ahead and make these speakers already (been waiting a while for this stuff to come..) but of course I can't just start soldering things together if the sound will be affected. Is this just a visual thing, or should I get in touch with EuropeAudio.com and sit out another month while they sluggishly send me some replacements?
Thanks for the help
Thats a good question...
If it were a small ferrite core used for RF etc then yes, the characteristics would change.
At audio and the low frequencies involved and the large tolerances, and the sheer size of the thing... well, I honestly don't know how detrimental this is. My feeling is probably not very.
If it were a small ferrite core used for RF etc then yes, the characteristics would change.
At audio and the low frequencies involved and the large tolerances, and the sheer size of the thing... well, I honestly don't know how detrimental this is. My feeling is probably not very.
Honestly, I don't know what the core is, can't seem to find out either..?
This is one of them, though for some reason the one in the pic doesn't have the 1/4" of extra metal on the end (where the crack is on mine) JANTZEN-5387 - Jantzen Wire non-ferrite cored coil 10,000mH 0,390Ohm 1,40mm - Europe Audio
Hopefully it really isn't a problem as Mooly said- I can attest to the size of the coil and outside position of the crack seeming insignificant, just want to make sure it's ok since I'm new to crossovers
Thanks guys!
This is one of them, though for some reason the one in the pic doesn't have the 1/4" of extra metal on the end (where the crack is on mine) JANTZEN-5387 - Jantzen Wire non-ferrite cored coil 10,000mH 0,390Ohm 1,40mm - Europe Audio
Hopefully it really isn't a problem as Mooly said- I can attest to the size of the coil and outside position of the crack seeming insignificant, just want to make sure it's ok since I'm new to crossovers
Thanks guys!
search suggests P core is "ferrous powder" material - why they wouldn't just say Sendust if thats what they're using?
the implicit large "air gap" of the bobbin means the cracks shouldn't have any real effect on the inductor value
presumably the "ferrous powder" has insulated particles to reduce Eddy current loss - again the barely visible cracks wouldn't change loss behavior
the implicit large "air gap" of the bobbin means the cracks shouldn't have any real effect on the inductor value
presumably the "ferrous powder" has insulated particles to reduce Eddy current loss - again the barely visible cracks wouldn't change loss behavior
Last edited:
Wow. These coated, non-oxidised ferric particles remind me of a kind of cassette I used to use making tapes for my car.
My biggest concern would be that one day, the cracked portion would break off, but then I rearrange crossovers from time to time. I'd be disappointed to get somewhere and then lose it to something like that. I'd rather stabilse it now by either strengthening it, or breaking it off for good.
My biggest concern would be that one day, the cracked portion would break off, but then I rearrange crossovers from time to time. I'd be disappointed to get somewhere and then lose it to something like that. I'd rather stabilse it now by either strengthening it, or breaking it off for good.
That's most definitely an iron powder core and it does look cracked but it's hard to be sure with the blur. I wanted to call it a surface imperfection until I saw it run through the radius visible at the front of the view. They probably measure within spec, however if the broken pieces manage to vibrate slightly as the flux swings through, and the attraction force can get quite high between pieces, it's going to cause distortion. How much distortion I couldn't say but it's not what you what to see when you're looking for high fidelity. If you had broken them you could probably fix em up by dunking them in some varnish, but as they are in that condition from the distributor I'd send them back.
I'm curious.. What value are they and how many did you get?
I'm curious.. What value are they and how many did you get?
Got some (hopefully) better pictures for you, this time with all four suspect inductors (beer bottle for size reference)
Judging by how the coils on both larger inductors appear pushed up to the side with the crack, it looks like these were all dropped together before packing. I say "before" because they were individually bubble wrapped, and the large and small coils were on opposite sides of the box with 2 inches of padding between them, yet they all have identical cracking patterns.
What if I were to drown the cracked end 1/4" in epoxy when I mount them on the crossover board? As long as sound hasn't been affected to this point, that would keep them safe from here on out
Judging by how the coils on both larger inductors appear pushed up to the side with the crack, it looks like these were all dropped together before packing. I say "before" because they were individually bubble wrapped, and the large and small coils were on opposite sides of the box with 2 inches of padding between them, yet they all have identical cracking patterns.
What if I were to drown the cracked end 1/4" in epoxy when I mount them on the crossover board? As long as sound hasn't been affected to this point, that would keep them safe from here on out
Last edited:
I have no problem with avoiding another month-long wait by using these, but I have to ask for advice because I am a total newb with crossovers, and don't know what I don't know in this area.
So to answer your question, I will be completely happy with these if you and other experienced members don't see any harm in stabilizing and using them as is. If you think they could cause problems even if stabilized when mounted, then I guess I'll just have to suck it up and wait out the backorder on these
I can't say for sure 100% that these would meet the identical spec of an undamged core.
That doesn't meant they won't... just that I don't know. It may be at extremes such as when a point close to saturation is approached that some small difference may occur.
I wonder if they have been crushed or something heavy has fallen on them. The ends may be little more than formers to make a bobbin shape and as the coil is wound around the main core then the effect may be non existent but as I say, I honestly don't know for sure.
That doesn't meant they won't... just that I don't know. It may be at extremes such as when a point close to saturation is approached that some small difference may occur.
I wonder if they have been crushed or something heavy has fallen on them. The ends may be little more than formers to make a bobbin shape and as the coil is wound around the main core then the effect may be non existent but as I say, I honestly don't know for sure.
If you have the means to measure the coils to see if the inductance is still right, then you could simply apply some super-glue/cyanoacrylate; let it seep into the crack: that should stabilise it. That is, if you don't want the hassle of exchanging it.
But if flaws like these cracks bother you, then I guess you'd be better off exchanging them for undamaged parts.
But if flaws like these cracks bother you, then I guess you'd be better off exchanging them for undamaged parts.
The inductance may still be correct but the core may saturate early if cracked.
Looking at the pictures it appears that the core itself would be undamaged.
Saturation is where the magnetic field in the core reaches a point that it can not be increased beyond,
http://en.wikipedia.org/wiki/Saturation_(magnetic)
You can have two identical "value" inductors, say a physically large and physically small one. That small one will saturate before the large one as the current increases.
I can't think of a good analogy for this. Maybe think of the inductors as "100 watt" resistors of "10 ohm" value whose 10 ohm value goes out of the window at saturation level, and the damaged one might end up as a 60 watt 10 ohm and so lose it's properties much earlier... not a good likeness I know
Some meters measure inductance... whether it would measure so large a value I don't know and it certainly wouldn't approach saturation limits.
http://en.wikipedia.org/wiki/Saturation_(magnetic)
You can have two identical "value" inductors, say a physically large and physically small one. That small one will saturate before the large one as the current increases.
I can't think of a good analogy for this. Maybe think of the inductors as "100 watt" resistors of "10 ohm" value whose 10 ohm value goes out of the window at saturation level, and the damaged one might end up as a 60 watt 10 ohm and so lose it's properties much earlier... not a good likeness I know
Some meters measure inductance... whether it would measure so large a value I don't know and it certainly wouldn't approach saturation limits.
Makes perfect senseSaturation is where the magnetic field in the core reaches a point that it can not be increased beyond,
http://en.wikipedia.org/wiki/Saturation_(magnetic)
You can have two identical "value" inductors, say a physically large and physically small one. That small one will saturate before the large one as the current increases.
I can't think of a good analogy for this. Maybe think of the inductors as "100 watt" resistors of "10 ohm" value whose 10 ohm value goes out of the window at saturation level, and the damaged one might end up as a 60 watt 10 ohm and so lose it's properties much earlier... not a good likeness I know
Some meters measure inductance... whether it would measure so large a value I don't know and it certainly wouldn't approach saturation limits.
So it all depends on the cores.. Wish I knew the guys in our NDT lab a bit better so I could get one of em to test these for cracks lol. I'll look at them closer tomorrow- it's getting crazy late so I need crash now, thanks for helping out!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.