Capacitor Placement

For help with setups and other technical issues.
User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Capacitor Placement

Post by Shadoweclipse13 » Thu Jan 07, 2021 3:05 am

So, I was doing some research for my pickup tester box and came across something that I don't know the answer to. Wondering if someone can explain the difference, if any.

Most schematics I've seen over the years (whether using for my own guitars, or referencing for a schematic I'm making), usually show the tone pot capacitor soldered in between the tone pot lug and the ground solder spot on the back of the tone pot. Like so:

Image

Tonight, I was looking up different wiring types (modern vs vintage 50s wiring), and found this article from Premier Guitar, Mod Garage: Three Ways to Wire a Tone Pot, which included this interesting picture...

Image

...which shows the capacitor soldered in between the volume and tone pots.

So, I'm wondering. Electrically speaking, does it matter if the capacitor is soldered between the volume and tone pots? The tone pot shunts certain frequencies to ground via the capacitor, and the big difference between the 3 wiring types shown here is what volume pot lug is connected to what tone pot lug, which in my opinion, could theoretically be wired with a plain wire (i.e. not necessary to be a capacitor).

Would there be a noticeable difference between the wiring between the pots being a plain wire or the tone capacitor, sound-wise?
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

User avatar
timtam
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 1892
Joined: Sun Oct 22, 2017 2:42 am
Location: Melbourne

Re: Capacitor Placement

Post by timtam » Thu Jan 07, 2021 4:33 am

Tone circuit = resistance(between tone pot tabs)/capacitance/ground OR capacitance/resistance/ground.
Order of resistance and capacitance (which comes first) doesn't matter; the only order that matters is that ground must be at the end. The length/type of wire hops along the way doesn't matter, as long as the overall route is one of the two above.

User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Re: Capacitor Placement

Post by Shadoweclipse13 » Thu Jan 07, 2021 5:55 am

Awesome. That makes an idea I have for my pickup tester box a little easier, and maybe a little more clever too! Thanks Timtam!
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

User avatar
jorri
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 2362
Joined: Thu May 07, 2009 1:53 am
Location: bath, UK
Contact:

Re: Capacitor Placement

Post by jorri » Thu Jan 07, 2021 9:47 am

The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.

User avatar
alexpigment
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 478
Joined: Mon Jun 04, 2018 3:02 pm

Re: Capacitor Placement

Post by alexpigment » Sun Jan 10, 2021 8:38 pm

jorri wrote:
Thu Jan 07, 2021 9:47 am
The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.
The way it's shown there is not how I commonly see 50s wiring done, but it may be effectively the same. I always use 50s wiring because it actually means there is *no* tone suck when turning down the volume. The only downside is that the volume goes down slightly when the tone is turned down, at least for 250k pots. I'll take that any day of the week.

User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Re: Capacitor Placement

Post by Shadoweclipse13 » Sun Jan 10, 2021 9:37 pm

jorri wrote:
Thu Jan 07, 2021 9:47 am
The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.
Interesting. So, you'd say that making a switch that can do the first two (modern and 60's wiring) is pointless? I want to have a switch that goes between modern and 50's, but if the 60's isn't any difference, leaving it off would be easier for me.

alexpigment wrote:
Sun Jan 10, 2021 8:38 pm
The way it's shown there is not how I commonly see 50s wiring done, but it may be effectively the same. I always use 50s wiring because it actually means there is *no* tone suck when turning down the volume. The only downside is that the volume goes down slightly when the tone is turned down, at least for 250k pots. I'll take that any day of the week.
Do you have a picture of how you usually see 50's wiring? I'm intrigued...
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

User avatar
adamrobertt
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 1842
Joined: Sun Mar 28, 2010 10:28 am
Contact:

Re: Capacitor Placement

Post by adamrobertt » Mon Jan 11, 2021 5:53 am

Shadoweclipse13 wrote:
Sun Jan 10, 2021 9:37 pm
jorri wrote:
Thu Jan 07, 2021 9:47 am
The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.
Interesting. So, you'd say that making a switch that can do the first two (modern and 60's wiring) is pointless? I want to have a switch that goes between modern and 50's, but if the 60's isn't any difference, leaving it off would be easier for me.

alexpigment wrote:
Sun Jan 10, 2021 8:38 pm
The way it's shown there is not how I commonly see 50s wiring done, but it may be effectively the same. I always use 50s wiring because it actually means there is *no* tone suck when turning down the volume. The only downside is that the volume goes down slightly when the tone is turned down, at least for 250k pots. I'll take that any day of the week.
Do you have a picture of how you usually see 50's wiring? I'm intrigued...
Typically the tone cap only starts to come into play when you start turning the volume/tone down. It doesn't mean it's pointless, as the effect when you turn the knobs will be different for the different schemes.

User avatar
jorri
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 2362
Joined: Thu May 07, 2009 1:53 am
Location: bath, UK
Contact:

Re: Capacitor Placement

Post by jorri » Mon Jan 11, 2021 8:47 am

alexpigment wrote:
Sun Jan 10, 2021 8:38 pm
jorri wrote:
Thu Jan 07, 2021 9:47 am
The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.
The way it's shown there is not how I commonly see 50s wiring done, but it may be effectively the same. I always use 50s wiring because it actually means there is *no* tone suck when turning down the volume. The only downside is that the volume goes down slightly when the tone is turned down, at least for 250k pots. I'll take that any day of the week.
Do you mean the wiring that uses three pins on the tone pot? I think thats referred to as fifties as well.

User avatar
jorri
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 2362
Joined: Thu May 07, 2009 1:53 am
Location: bath, UK
Contact:

Re: Capacitor Placement

Post by jorri » Mon Jan 11, 2021 8:52 am

Shadoweclipse13 wrote:
Sun Jan 10, 2021 9:37 pm
jorri wrote:
Thu Jan 07, 2021 9:47 am
The first two are identical electronicaly speaking.

The third, 50s, has tone pot after volume. I dont know if that affects something. If it did it would be something like having more tone suck when turn down volume. Volume on full, all three are same schematically.
Interesting. So, you'd say that making a switch that can do the first two (modern and 60's wiring) is pointless? I want to have a switch that goes between modern and 50's, but if the 60's isn't any difference, leaving it off would be easier for me.

alexpigment wrote:
Sun Jan 10, 2021 8:38 pm
The way it's shown there is not how I commonly see 50s wiring done, but it may be effectively the same. I always use 50s wiring because it actually means there is *no* tone suck when turning down the volume. The only downside is that the volume goes down slightly when the tone is turned down, at least for 250k pots. I'll take that any day of the week.
Do you have a picture of how you usually see 50's wiring? I'm intrigued...
It might not make much difference as i say.

Yes the fourth way and dont know if alex was referring to:
-look at a standard rhythm circuit, the tone is wired using three pins like the volume is but has a tone cap in there. That might be more difference? But the practicality of having that on a switch I am not sure, other than, well jazzmasters have a rhythm circuit that does it so there may well be a use. Its different in that it uses a 50k pot. Checking the Jag lead circuit it is in fact wired this way with its 1meg plus some kind of resistor (for less volume loss?) and could be more like that.

User avatar
alexpigment
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 478
Joined: Mon Jun 04, 2018 3:02 pm

Re: Capacitor Placement

Post by alexpigment » Mon Jan 11, 2021 10:17 pm

To answer the questions above, I do it as shown in the top diagram here:

https://www.premierguitar.com/articles/ ... aster-pt-2

It’s just a quick 30 second solder job to move the wire on the vol pot from the outer lug to the middle lug. It also is slightly brighter and aggressive at full vol/tone despite what people will tell you “should” happen. Anyway, I’ve never looked back.

User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Re: Capacitor Placement

Post by Shadoweclipse13 » Mon Jan 11, 2021 11:08 pm

alexpigment wrote:
Mon Jan 11, 2021 10:17 pm
To answer the questions above, I do it as shown in the top diagram here:

https://www.premierguitar.com/articles/ ... aster-pt-2

It’s just a quick 30 second solder job to move the wire on the vol pot from the outer lug to the middle lug. It also is slightly brighter and aggressive at full vol/tone despite what people will tell you “should” happen. Anyway, I’ve never looked back.
Interesting. Thanks for the link! I like the switch that goes between both options. That might be fun to install in a guitar...
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

User avatar
timtam
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 1892
Joined: Sun Oct 22, 2017 2:42 am
Location: Melbourne

Re: Capacitor Placement

Post by timtam » Tue Jan 12, 2021 12:04 am

As Whacker says in the article, the two ways shown for 50s wiring are electrically identical - one is cap->resistance->ground, the other resistance->cap->ground. Same deal.
Image

Image

The tone control in the jag/JM rhythm circuit has a somewhat unusual wiring ...
Image

SD has also circulated a variation (open lug on 50k tone pot) that AFAIK has never been used by Fender ...
Image

User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Re: Capacitor Placement

Post by Shadoweclipse13 » Tue Jan 12, 2021 1:32 am

What would be the difference in variations for the rhythm circuit, sound-wise? Any point to one vs the other? My instinct would be to wire a rhythm circuit the way Fender designed...
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

User avatar
timtam
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 1892
Joined: Sun Oct 22, 2017 2:42 am
Location: Melbourne

Re: Capacitor Placement

Post by timtam » Tue Jan 12, 2021 2:02 am

I haven't compared the SD variation to the Fender standard rhythm circuit tone pot wiring but I have a note from somewhere attached to the SD variation ... "rhythm circuit tone pot wiring swapped to prevent VOL roll off with tone roll off ".

One reason for noting that the SD diagram is different is that a few people have probably used it over the years to wire their partsmasters without noticing the wiring difference.

User avatar
Shadoweclipse13
PAT. # 2.972.923
PAT. # 2.972.923
Posts: 9828
Joined: Fri Feb 07, 2014 9:22 pm
Location: Stuck in the dimension of imagination

Re: Capacitor Placement

Post by Shadoweclipse13 » Tue Jan 12, 2021 2:10 am

Very interesting. I've used SD schematics now and then, either for a complete guitar wire-up, or for bits and pieces during research for some of the schematics I've made for people around here. I wonder if I've used their JM/Jag rhythm circuit and not realized it...
Pickup Switching Mad Scientist
http://www.offsetguitars.com/forums/viewtopic.php?f=8&t=104282&p=1438384#p1438384

Post Reply