The Black Hole......

John Curl
 

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Concern

An inductor with significant resistance can overheat, and if a conjugate circuit directly across an amp fails the impedance may drop to near 1 ohm. You won't necessarily know or hear it until it's too late (smoke/fire)...

Your customers have asked about this..
R2 is the only resistor marked with a minimum of 10watts. So I would assume that there is a lot of power going trough L4.

So now to the question. Is it beneficial to get a low ohm L4 coil?
Would there be any detriment in switching to the smaller Jantzen 4mh and 18mH inductors if I already have the Erse SuperQ inductors? Wanting to put the crossover below the speakers and will be tight on space.

I've attached a plot of potential dissipation for a 50W amp, and the low impedance that will arise if this 18mH(3.2ohm) inductor was to short after becoming hot.. (simple saturation of the core would also reduce the impedance).

watts.png
Short.png
Hamlet_Xover_Layout.gif
 
Inductor heat calculations for conjugate (L4)

You replied
The copper will absorb a lot of energy as it has thermal mass which also means it will heat up much more slowly than the resistor.
Mass plays a role in the short term. Device dissipation depends on the ability of heat to escape, which is partly dependent on surface area.

1R8 10W Resistors
The inductor will dissipate around 75% more than the resistor in this circuit. Even by your own estimate here it needs to be able to deal with 17.5W. It has a surface area of around 70cm2.

According to the Transformer And Inductor Design Handbook (Figure 6-4), the allowable dissipation is preferrably no more than 2W and up to 5W.

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I'm confident the man got a clause written on a piece of paper stored in his back pocket saying "I'm not responsible for anything I have ever expressed in my whole life, in particular anything remotely related to audio."

ps. where does those quotes come from, hyperlink is missing.
 
If not, I would have asked.

"We don’t so much smell fart levels as fart (digestion?) mechanisms."

"You need to understand the fart before you can design a test that will quantify it sensibly.

"Is in one...."

Awful handling of the queens language to boot.

Also very poor idea to design a tailored measurement system from what you think you are about to measure as it will probably skew your readings. All in that post is so corny that it must be trolling. It cant be a sincere addition to this fine forum. It just can not.

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