A very technical question

Re: A very technical question

freefrog said:
LOL... :-))

So, let's try again...



Look again this schematic (I'm not its author but it's a consensual schemo often used in spice modeling by various winders, techs, engineers and so on):

https://www.talkbass.com/attachments/upload_2016-11-3_13-3-53-png.981681/

V1, L pickup, R pickup and C pickup sum up the four basic properties of any magnetic transducer: voltage, inductance, resistance, stray capacitance (IOW, these 4 components = 1 single pickup).

"R tone" is the standard tone pot. "C tone" is the standard tone cap. These R and C are in series with each other and their order doesn't matter. But the whole network is in PARALLEL with the pickup, like any tone control.

Then, there's C2, named "Bass cap" on the schematic but it's probably a typo error: C2 is a bass CUT capacitor, in SERIES with the pickup.

The guy who did the schematic did know his stuff: he has wired the standard tone control to ground THEN the bass cut cap in series towards the output. Because if he had put C2 between "C pickup" and "R tone", the tone pot would behave abnormally, by lowering the volume and thinning out the tone..

And anyone will easily check it with a pickup, two pots, two caps and a few alligator clips... :-)
Click to expand...

Yes, but in that diagram the tone pot is NOT in series with the vol pot. Therefore this discussion of the tone pot acting like a vol pot (whether the cap is before or after the tone pot) is irrelevant. This was my problem with your post. The tone pot is NOT in series with the vol pot and will NOT act as another vol pot even if the cap is placed before it.
 
Re: A very technical question

GuitarDoc said:
The tone pot is NOT in series with the vol pot and will NOT act as another vol pot even if the cap is placed before it.
Click to expand...

He, he, he... ;-))

Try it : pickup output > capacitor in series > volume / tone controls in any order > output.
Lower the tone pot.
Listen.

It should suffice and make "irrelevant" any further comment. :-)
 
Re: A very technical question

frankfalbo said:
I mean long screws, and I mean on The 3 bass strings. It elongates the magnetic field, and stretches out the return path. Don’t worry about what anyone has said about it adding or reducing bass. It’s also an attack/decay and string separation thing. If you do try it I would love to hear your experience.
Click to expand...

Hi, did this, just reportingback. Indeed it seemed to give more clarity and definition in the upper frequencies, but also lowered the bass frequencies, going all woofy, lows shifting to low lows. Strings had a more scooped sound so to say.

It also affected the attack, sounding more like all my other pups. I put the short screws back in, still much bass but less woofy, a bit less string separation but the sweet piano like attack is back (it's a bad description) as is the violin like timbre, which is what makes the pup unique.

I guess a series cap to dial the lows back will be the only option to deal with the bass and maintain the pup's original character.

Oh, before you all go and buy those MK PAF plus neck pups, the axe itself sounds a bit bland acoustically and it's a picky piece of wood. I tried various pups and mods in the bridge but in the end only the 59 seemed to work. But the axe just pairs well with the A4 modded MK PAF plus.
 
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Re: A very technical question

I'm really sorry if I'm hijacking this thread. Just trying to understand.

So, when you're talking about putting the cap either before or after the tone pot, you're referring to the "C2" ("bass cap") in your diagram...NOT the "Ctone" cap. Is that correct? If so, that's where I have been so confused.
 
Re: A very technical question

GuitarDoc said:
I'm really sorry if I'm hijacking this thread. Just trying to understand.

So, when you're talking about putting the cap either before or after the tone pot, you're referring to the "C2" ("bass cap") in your diagram...NOT the "Ctone" cap. Is that correct? If so, that's where I have been so confused.
Click to expand...

Hi Doc,
If the question is for me as it appears to be the case: thx for asking and yes, all of my sentences about the "cap in series" were referring to "C2", not to "Ctone".
I was presupposing it to be clear on the basis of the previous posts (1 to 6). I was wrong. That's life. :-)
If this last precision contributes to dissipate any mutual misunderstanding, I'll be glad.

WDeeGee, let us know if a cap in series with your pickup is a solution to your problem or not. BTW, feel free to experiment with various values: 4,7nF (0.0047µF) is a capacitance often used for such bass cut / high pass filters but your PU might require a higher or lower value than this. I hope you'll solve your issue. :-)
 
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