Air Core Inductors

[djk]

"an iron core:

A multitude to choose from, some good, some execrable.

[Deang]

I assumed the DCR on the UT air core would be close to .4, but a measurement gave me .55 ohms - a little too high I think. I asked them to wind me six using 12 gauge wire. This should bring the DCR down to .3 or lower. I think I'm going to use these on special builds or at request. They may not look as nice as the Solens or the Erse "perfect lay" types, but the prototype they sent me is a solid part and I don't want to walk away from it. All these folks do is wind, and it shows. The fact that I can offer it for a little more than half as much is a plus too. A 2.5mH 14AWG Erse air core from Partsexpress goes for roughly $40.00.

[DrWho]

Got any good ones you can recommend Dennis?

Sent from my SAMSUNG-SGH-I747 using Tapatalk

[Deang]

I quit using that app 15 minutes after I downloaded it.

UT 2133-BV

Erse Super 'Q'

Jantzen P-Core

I've lost confidence in the Madisound Sledgehammer. I've got five I have to send back because the laminations can be pushed back and forth through the windings.

[DrWho]

Wow, that's annoying that tapatalk adds stuff to your posts....way annoying. I only used it for that one post too, haha.

[DrWho]

"Not helpful Dennis, not even a little bit -- all we know is what we've always known, that Wilson is ripping people off in the worst kind of way. Man, you were supposed to blow me away with at least a paragraph of something I couldn't understand."

Hey, I try.

Barkenhausen noise (sudden, discontinuous jumps in magnetization, sudden changes in the size and orientation of ferromagnetic domains, or microscopic clusters of aligned atomic spins) is virtually inaudible in a well designed inductor.

This would argue for fine laminations of a high permeablity material. M6 is fine for inductor cores (Madisound SledgeHammer), solid cores (Madisound Sidewinder), and ferrite drum cores (certain Klipsch products), have room for improvement.

Small signal transformers (mic, line, etc) can benefit from better materials than M6 (but at a higher cost).

"if you have a 4inch exhaust system well things move much more freely and you get alot more power!!!"

So, if bigger is better, should I go to a 6"? How about I just take off the manifold?

So is this an argument that "analog filters" really aren't "analog" and have quantized steps in the output???

[Deang]

You're a trip Mike, how did you pull that conclusion from that information?

[DrWho]

"A coil of wire wound on the ferromagnetic material can demonstrate the sudden, discontinuous jumps in magnetization. The sudden transitions in the magnetization of the material produce current pulses in the coil."

http://en.wikipedia.org/wiki/Barkhausen_effect

I just brought it up because the picture looked like stair steps, and I thought it'd be fun to point that out.

It turns out that it is very true that the analog world is quantized. There's that whole field of quantum mechanics....and ironically, it plays a big part in high fidelity audio circuits. I might even say that it's often a limiting factor.

[djk]

"I've got five I have to send back because the laminations can be pushed back and forth through the windings."

JBL inductors were constructed with the same type of construction as well.

The line-operator adjusted the core until it was the correct value, then fixed it into position with hot-melt glue.

I use both Erse and Sledgehammer, just depends on the rest of the parts on order who I give the order to.

Edited November 25, 2013 by djk