Partial Coil Split with HPF - or is it?

ICBM

andyg_prs said:

So that leaves me confused as to why the capacitor is brightening up a muddy sound. 

Because it also allows high signal frequencies through!!

andyg_prs

ICBM said:

andyg_prs said:

So that leaves me confused as to why the capacitor is brightening up a muddy sound. 

Because it also allows high signal frequencies through!!

But the capacitor is in series and before the resistor.....so how does it manage to let more high frequencies through than would pass in its absence?

ICBM

andyg_prs said:

But the capacitor is in series and before the resistor.....so how does it manage to let more high frequencies through than would pass in its absence?

The cap passes high frequencies and blocks low frequencies. Signal frequencies add, hum frequencies cancel.

The cap and resistor values need to be chosen so the relatively small amount of hum will balance with that from the other coil and cancel out.

I can't think of any simpler way to explain this!

andyg_prs

No, and I apologise.  I think I understand a lot.  Let me summarise my understanding.

The resistor is blocking the red/black signal from going to ground completely.

The capacitor is preserving the low frequencies on the red/black coil - and that includes the hum frequencies, and these are cancelling the low/hum frequencies on the green/white coil.

The capacitor also acts on the red/black coil, allowing high frequencies to pass - and this might be where I'm going wrong.  I was thinking that the high frequencies were passing to ground and getting 'killed' in the same way as I was thinking of the red/black coil being shorted to ground.....or now with the resistor, partially shorted to ground.

Now that some of the red / black coil is not being shorted to ground (because of the resistor), the treble that is being passed through the capacitor is actually forming part of the signal that reaches the amp?

If so, there's my answer....and the issue is me not being able to really conceptualise what is happening when the resistor prevents all of the red/black coil being shorted to ground.  I can accept it and have witnessed how it manifests itself, but I don't intellectually really grasp what is happening.

Anyhow, not withstanding my last paragraph.....if the rest of what I have said is correct, I really ought to stop bothering you!

Cheers,
Andy

ICBM

That's kind-of it, yes .

It's a quite difficult one to understand, I know - it's the difference between cancelling some but not quite all of the frequencies you don't want, as well as allowing most of the ones you do through. As you've discovered, it's sensitive to the values of the resistor and the cap because both are nearly a full cut, but not quite.

(And not helped by me getting the two coils the wrong way round in an earlier post .)

andyg_prs

Thank you so much for your time. Learning is a gift!  If I ever find the time, or manage to retire at some point, there are so many things I’d love to study; electronic engineering, the trades (gas / electrical) and welding!

For now I just hack my way along!

 Thanks again