OT Crossover Wiring

[mah]

https://www.manualslib.com/manual/36...Schematic.html

Example, N501 8A. L.F. circuit.

Four resistive(power consuming components) in series configuration.

Amp to speaker wire(2x6 = 12 ft.), internal speaker cabinet and crossover wiring(2x3 = 6 ft.), 2 ohm DCR choke, driver Re = 6.3 ohm.


*18 AWG wire: 0.006385 ohm per ft. 18 ft. = 0.115 ohm

Current in circuit to give 3 Watt in Re is 0.69 amp. Amplifier power required to deliver 3 watt into Re is I(squared) x R( total in series),

0.69 x 0.69 x (0.115 + 2.0 + 6.3) = 4 watt


*8 AWG wire(0.0006 ohm per ft.): gives 0.69 x 0.69 x(0.108 + 2 + 6.3) = 3.96 watt from the amplifier.

A difference of 0.04 watt, giving a power change = 0.044dB at the amp, less at the driver.


Inaudible.


*If the wire had zero ohms resistance the amp power would only reduce to 3.95 watt for 3 watt at the driver.


*Using a 0.6 ohm choke and 18 AWG wiring requires 3.34 watt from the amplifier, a 0.66watt (0.78dB change).


I wouldn't get too fussed about the wiring.

[BillWojo]

That's the kind of post I like, based in real factual engineering science that proves what a lot of us have been saying all along.
Never the less, someone will be by shortly to tell us that we simply don't understand.
By the way, your calculations were not based on the ever so important Fulton length of 53.1589632789541 inches. At that specific length, all belief in physics, science and engineering is suspended and the resistance of the wire, if doubled drops to zero.
It's true, I heard it on the internet.

BillWojo

[Phil-G]

at some point, Todd will tire of all of this and pull the plug. then we will all have to find another forum.
moderation is the key

[mah]

Tire of what, exactly, Phil? Factual posts?

[GM]

I wouldn't get too fussed about the wiring.

Yeah, there's some losses involved that's not factored in, but still will be below human hearing threshold. After taxes [this mandatory IRA distribution really 'hit' me much harder than I'd assumed!], my next goal is to figure out how to get win10 to accept Office 2k, so I can use my various Excel calculators, which will allow me to do all the calcs using the math that the electrical world runs on, then onto MathCad 2k Pro as without them I'm not much smarter math wise than a box of rocks. I tried loading win XP Pro on an old Lenovo laptop, but no joy and according to the computer folks at Fry's, its architecture is the problem, so must find an even older LT or desktop that's not worn out [fat chance!], though guessing they just want to sell me the new 365 you have to pay an annual fee for, which ain't gonna happen just on general principle. Sure wish Open Office could run Excel micros.

GM

[GM]

at some point, Todd will tire of all of this and pull the plug. then we will all have to find another forum.
moderation is the key

FYI, he didn't ban Romy the Cat [I forget his Russian name] or anybody when I got ganged up on ~a decade? ago, so doubt this current state of affairs will ruffle any feathers.

If he does, I'll just do all my posting on DIYaudio or if I get too curmudgeonly in my dotage for them I'll go back to the HE forum where I started after the mail BBs became so violent.

GM

[mah]

Has Romy met his match, here?

[GM]

You've obviously never 'crossed swords' with him!

GM

[mah]

Jeff, I also showed an example using 8 AWG wiring and an example using 'zero resistance' wiring - negligible difference. Little difference from the 18 awg example used for reference.

The contribution to power loss by the wiring is less than 1.4% for the 18 AWG example and less than 0.014% for the 8 AWG example. Insignificant.

You don't like It? Prove otherwise.

[Elitopus1]

I agree with the first post. Its the correct way to calculate things. I too am trained like an EE, just not by the military.

I also believe in something we call "FM" in aviation. Its short for "F'ing magic". Sometimes things work when they shouldn't. I think audio is 90% facts and 10% FM.