# Know lots about potentiometers



## noodles

*What is the difference between 250K & 500K pots? *

Either 250K or 500K pots can be used with any passive pickups however the pot values will affect tone slightly. The rule is: Using higher value pots (500K) will give the guitar a brighter sound and lower value pots (250K) will give the guitar a slightly warmer sound. This is because higher value pots put less of a load on the pickups which prevents treble frequencies from "bleeding" to ground through the pot and being lost. For this reason, guitars with humbuckers like Les Pauls use 500K pots to retain more highs for a slightly brighter tone and guitars with single coils like Stratocasters and Telecasters use 250K pots to add some warmth by slightly reducing the highs. You can also fine tune the sound by changing the pot values regardless of what pot value the guitar originally had. 

*What is the difference between Audio and Linear taper pots?*

Audio and Linear taper pots have the same total resistance but differ in which position of rotation the pot will reach the 50% value. Linear pots are usually marked with a B or Lin (examples 250KB, B250K, 250K Lin) and will reach 50% of its total resistance in the 50% rotation point. Audio taper pots are usually marked with an A or Aud (examples 500KA, A500K 500K Aud) and will decrease most of the resistance in the last 50% of the rotation. This can give a more gradual audio reduction is some cases. Most manufactures and builders either use Audio taper pots for volume and tone or linear for volume and audio for tone. However, if a problem of exists where a volume or tone pot has no effect on the sound, try a changing the taper. How to check the taper with an ohm meter: Set the pot to the center position (50% rotation) and measure the resistance between the center pin and each of the outer pins. If the the resistance is equal (50% of the pots value) the pot is linear. If the values are not equal, the pot is an Audio taper.

*What is a Fender TBX tone control and how does it work? *

Some Fender guitars come equipped with a special pot called a TBX Tone Control T (treble) B (bass) X (Cut) that cuts either treble or bass instead of a tone pot that cuts treble frequencies only. This is done with a ganged 500K-1M ohm control pot that is wired to work as a low-pass filter in one direction and a high-pass filter in the opposite direction. A center detent in the middle position is provided for the off or "flat" position. Although Fender altered their Start tone configuration to have the TBX control the middle and bridge pickups, it can be also be wired as a master treble/bass control. The TBX can also be used in place of any standard tone control on any guitar.

*What is a Fender No Load tone control and how does it work?* 

The Fender No Load Pot is used on some USA Strats, Teles and Fender basses and is wired like a standard tone control. From settings 1-9 it works like a standard tone then clicks in at 10 (full clockwise/ bright setting) and removes the pot and capacitor from the circuit. This eliminates the path to ground that exists with standard pots even in the full treble position. By eliminating the path to ground thru the pot, the only load on the pickup is the volume pot. So if 250K pots are used, the load is reduced from 125K to 250K and if 500K pots are used, the load is reduced from 250K to 500K (high resistance = low load) The reduced load allows more power output from he pickup and reduces the amount of high frequencies that bleed off to ground. This gives a noticeable increase in brightness and output in the full treble setting. The no load pot can be used in place of any standard tone control on any guitar or bass. 
How does the tone capacitor value affect the sound of the guitar? 

Most guitars and basses with passive pickups use between .01 and .1MFD (Microfarad) tone capacitors with .02 (or .022) and .05 (or .047) being the most common choices. The capacitor and tone pot are wired together to provide a variable low pass filter. This means when the filter is engaged (tone pot is turned) only the low frequencies pass to the output jack and the high frequencies are grounded out (cut) In this application, the capacitor value determines the "cutoff frequency" of the filter and the position of the tone pot determines how much the highs (everything above the cutoff frequency) will be reduced. So the rule is: Larger capacitors will have lower cutoff frequency and sound darker in the bass setting because a wider range of frequencies is being reduced. Smaller capacitors will have a higher cutoff frequency and sound brighter in the bass setting because only the ultra high frequencies are cut. For this reason, dark sounding guitars like Les Pauls with humbuckers typically use .02MFD (or .022MFD) capacitors to cut off less of the highs and guitars like Strats and Teles with single coils typically use .05MFD capacitors to allow more treble to be rolled off. Keep in mind that the capacitor value only affects the sound when the tone control is being used (pot in the bass setting) The tone capacitor value will have little to no effect on the sound when the tone pot is in the treble setting. 

*Does the number of control pots used affect the sound?* 

Yes: Since the load on the pickups is determined by the total parallel resistance of all pots that are being used at a atime, using fewer pots will reduce the overall load and give a slightly brighter sound. Also, connecting more pots is the same as using lower value pots, two 500K pots will loose or "bleed" the same amount of treble frequencies as one 250K pot. To lessen the effect, switching should be designed (when possible ) to remove pots from the circuit when the related pickup is not selected. An example of this is the Les Paul: bridge controls are out of the circuit when in the selector is in the neck position and the neck controls are out of the circuit when the selector is in the bridge position. 

*Pickup and Switch FAQs*

*What is the difference between single & four wire humbuckers? *

Single wire humbuckers, (also called single conductor) have the link between the two individual coils hard wired together internally. They also have one coil lead hard wired to ground. This means the pickup can not be coil split, reverse phased or switched to parallel. These pickups usually have a metal braided coaxial output wire. (braid=ground and the center wire=hot) Four wire humbuckers have both wires from each coil plus a ground wire (usually bare wire) all in one cabel to allow thw cois to be split, reverse phase or switched to parallel with custom and optional switching. For standard humbucker wiring (series-in phase) two of the wires (series link/ coil tap wires) are connected together and the remaining two wires are used as hot and ground. (the wire used as the ground is combined with the bare ground wire and soldered to the back of the volume pot or other ground spot. The wire used as hot is soldered to the pickup switch or volume pot. 
What are the differences between coil tap, series/parallel & reverse phase? 

*With a single 4 wire humbucker, there are six possible modes*. 

1. Series-In Phase This is the standard humbucker wiring. Maximum power output with strong bass and smooth attack. (hum canceling) 
2. Single Coil (South) Just the South coil of the pickup alone. Good traditional single coil tone with a sharper attack. (not hum canceling) Use in combination (series or parallel) humbucker in "North coil mode" or a standard single coil (north) for a hum canceling Strat/ P.R.S. style tone. 
3. Single Coil (North) Just north coil of the pickup alone. Almost the same tone as the south coil but slightly different due to its different position. (not hum canceling) Use in combination (series or parallel) with another humbucker in "South coil mode" or a standard single coil (South) for a hum canceling Strat/P.R.S. style of tone. 
4. Parallel-In Phase Great single coil style tone with no hum. Best option for clean, bright tone without the noise of standard single coil wiring. Strong treble with crisp attack but lower power output. (hum canceling) 
5. Series-Out of Phase Thin "phased" sound with good power. Great for funk. (not hum canceling) 
6. Parallel-Out of Phase Thinner "phased" sound with low power. (not hum canceling)

Original source: Potentiometers FAQ at GuitarElectronics.com


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## ohio_eric

Guitar Electronics.com is a good resource in general. That's a good link.


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## JPMDan

so 500k pot is better for volume, audio or linear? I'm looking to order 2 new pots for my ESP.


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## SeanC

For an X2N would it be overkill to use a 500k pot? Or is it better to use a 250k?


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## D-EJ915

Vic Rattlehead said:


> For an X2N would it be overkill to use a 500k pot? Or is it better to use a 250k?


I use a 500k with mine and it sounds awesome, remember that a 250k pot is just a 500k turned down a little bit.


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## MF_Kitten

D-EJ915 said:


> I use a 500k with mine and it sounds awesome, remember that a 250k pot is just a 500k turned down a little bit.



does that mean that you can change the K value of a pot?


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## BigM555

I ran across that link myself not too long ago.

Great one!


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## TomAwesome

Great info!


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## lostcomingdown

@mfkitten:

no, you can't change the K rating of a pot. well. kinda. see, variable resistance is kinda what pots do. it's a variable resistor soldered into place between the hot wire and ground points, and depending on where it's set, it bleeds off a little bit of your signal/all of your signal to ground, which makes for 0 potential between ground and input, which makes for no potential difference at the amplifier input, and no sound output. with the signal your guitar's putting out being so small, from a design standpoint, there's no difference between a 250, 500, and 1M pot, but um. they sound different, like the other guy said. sorta. someone kick me if i'm wrong, it's been known to happen.


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## Quicksilver689

nice link - thx for sharing!


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## Ultramog

Thanks for posting this. It helps as I spend waaay too much time drawing & redrawing pickup selector diagrams at work. 

Is there a No Load Volume Pot? Sounds like a dumb question, but here's what I'm after: 3-way toggle (Single Coils in Series, 2 Humbuckers, Single Coils in Parallel) plus 2 volumes. But I want to be able to get take individual pickups out of the circuit when volume is completely off.


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## MaKo´s Tethan

Just to leave it up, may be useful for somebody...

http://www.sevenstring.org/forum/pickups-electronics-and-general-tech/98265-the-secret-life-of-pots-if-you-wanna-know.html


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## Miss D Corona

You should change the title from 'potentiometers' to 'pots'


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## Hasmamagee

Hey everybody I put a thread in earlier about a wiring diagram for a guitar with 3 humbuckers 3 tone pots and 3 volume pots so far no one has commented but maybe one of you guys know some help would be seriously appreciated


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## JonnyDeath

MF_Kitten said:


> does that mean that you can change the K value of a pot?



In a sense, yes.
You can add a fixed value resistor in either series or parallel but ultimately no matter how you change the perceived value, you can't make a 250K pot function like a 500 K or 1 meg, only vice versa.


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## filipe200x

I have a 7 string with two humbuckers. I'd like to install a fender no load, would that be ok with this pot being a 250k? Also if not, does the fender TBX turns off at the center positions allowing the same amount of highs as if it had no pot, or does it just work like a regular pot on 10?


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## Scookers

filipe200x said:


> I have a 7 string with two humbuckers. I'd like to install a fender no load, would that be ok with this pot being a 250k? Also if not, does the fender TBX turns off at the center positions allowing the same amount of highs as if it had no pot, or does it just work like a regular pot on 10?



I used Fender No-Loads on my Rogue 7-string Frankenstein. There is a modification to use the Fender No-Load as a volume pot. They are 250K pots and they work. The only problem is when you turn the thing down to 0, it still lets some signal through. A noise gate fixes this pretty well. I also used a .002 uF capacitor in the tone circuit. It also has a Dimarzio Evolution 7 at the bridge. It's hot as hell. There is a special way to wire this thing up as a volume pot. I screwed it up at first and brought it to a guitar shop where some guy took all of my work and screwed it right the hell up. Then he told me it couldn't be done. This made me bound and determined to find the fuck up and make it work. I looked at the diagram again and said, "Duh!" It works great now. I might have to tear apart my guitar and make up the diagram. It's been years since I did it. Anyway, the downside is the volume not turning down all the way. The upside is a hot as hell guitar. Was I super impressed with it? Not really. Otherwise I would have done it to all of my guitars. Try it out and see if you like it. I just know that particular guitar is crazy hot. Let me know if you need the diagram. I'll make it for ya. I found it on guitarnuts.com, but can't find it there anymore.


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## yingmin

noodles said:


> *What is the difference between 250K & 500K pots? *
> 
> Either 250K or 500K pots can be used with any passive pickups however the pot values will affect tone slightly. The rule is: Using higher value pots (500K) will give the guitar a brighter sound and lower value pots (250K) will give the guitar a slightly warmer sound. This is because higher value pots put less of a load on the pickups which prevents treble frequencies from "bleeding" to ground through the pot and being lost. For this reason, guitars with humbuckers like Les Pauls use 500K pots to retain more highs for a slightly brighter tone and guitars with single coils like Stratocasters and Telecasters use 250K pots to add some warmth by slightly reducing the highs. You can also fine tune the sound by changing the pot values regardless of what pot value the guitar originally had.


Can someone explain to me why this works the way it does? I've been asking around, and even my guitar tech, who is otherwise never without an answer for things like this, couldn't explain it to me. It seems to me like it should be the opposite: since 500K pots have higher impedance, wouldn't they be putting more resistance on the signal? Conversely, using 25K pots like for EMGs with passive pickups totally chokes the tone, but by my way of thinking, it should let the most signal through. What am I missing? I'm not amazingly knowledgeable about electronics, so there's obviously something about this I'm misunderstanding, but can anybody tell me what?


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## SD83

yingmin said:


> Can someone explain to me why this works the way it does? I've been asking around, and even my guitar tech, who is otherwise never without an answer for things like this, couldn't explain it to me. It seems to me like it should be the opposite: since 500K pots have higher impedance, wouldn't they be putting more resistance on the signal? Conversely, using 25K pots like for EMGs with passive pickups totally chokes the tone, but by my way of thinking, it should let the most signal through. What am I missing? I'm not amazingly knowledgeable about electronics, so there's obviously something about this I'm misunderstanding, but can anybody tell me what?


I'd like to hear the answer as well, as I have the same trouble understanding it.


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## veggie7sXe

SD83 said:


> I'd like to hear the answer as well, as I have the same trouble understanding it.


 
Active pickups are wound to be low outputs. But i guess with the battery juice it makes them spit out over 500 ohms of aggression.


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## Racerdeth

yingmin said:


> Can someone explain to me why this works the way it does? I've been asking around, and even my guitar tech, who is otherwise never without an answer for things like this, couldn't explain it to me. It seems to me like it should be the opposite: since 500K pots have higher impedance, wouldn't they be putting more resistance on the signal? Conversely, using 25K pots like for EMGs with passive pickups totally chokes the tone, but by my way of thinking, it should let the most signal through. What am I missing? I'm not amazingly knowledgeable about electronics, so there's obviously something about this I'm misunderstanding, but can anybody tell me what?



I could be wrong but I think it's resistance between the signal and ground rather than the signal and hot, so when the vol's turned up full you have the full 500k resisting the signal going to ground, but if you had a 250 you'd only have 250k of resistance between ground, so more of your signal bleeds off. I'd appreciate someone to confirm this though.


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## Racerdeth

Correction- it works as a potential divider. Voltage divider


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## brutalslam

I'm looking to put new pots/cap in my Ibanez RG7421 when the new pickups go in. Can anyone tell me if this is the right stuff? 

Bourns 500K Audio Mini Guitar Pot

and these caps, just 1 set (.022 and .047)? 

Orange Drop .022 & .047 Microfarad Tone Capacitors


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## whosdealin

Great thread.... Maybe we can talk a bit about capacitors also. I havent experimented much with them and was wondering if anyone can share there experiences of trying different types, values.....and what the change in tone was. Thanks !


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## guitarneeraj

yingmin said:


> Can someone explain to me why this works the way it does? I've been asking around, and even my guitar tech, who is otherwise never without an answer for things like this, couldn't explain it to me. It seems to me like it should be the opposite: since 500K pots have higher impedance, wouldn't they be putting more resistance on the signal? Conversely, using 25K pots like for EMGs with passive pickups totally chokes the tone, but by my way of thinking, it should let the most signal through. What am I missing? I'm not amazingly knowledgeable about electronics, so there's obviously something about this I'm misunderstanding, but can anybody tell me what?



Basically, your guitar's pickup(s), the volume pot, tone pot, tone capacitor, and cable impedance form one RLC network, in essence a resonant low-pass filter of 2nd order to be precise.

If you're still with me, following is the circuit diagram for a pickup's equivalent circuit and the external load which consists of(all not shown) volume pot, tone pot, tone capacitor and cable impedance.







And here is how a resonant low pass filter looks like :






Changing the value of any of the components in this RLC network will affect the tone i.e. output of the instrument. 

The tone pot affects the frequency axis, while the volume pot affects the boost/cut around the center frequency.

With me so far?

Now, the higher the value of the tone and volume pots, the more the high end roll-off (steepness of the filter beyond cutoff frequency). Wikipedia has a good article on filter roll-off, if you're more interested further in the mathematical part of it. Roll-off - Wikipedia, the free encyclopedia

Also, just my  this guy has excellent demos:


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## oliviergus

Where can I get a "slow" pot in europe? The pot I have in my ibanez atm is too easy to turn.


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## Cannibalbritney

In all my frankentstrats I have one humbucker *bridge* and I wire my pickups direct to the output jack... no pots... maybe an on off switch... but i like it direct. I mean in most cases you have a tuner or a bypass pedal on your rig anyway... so just stomp it to remove noise... but in my opinion it sounds MUCH better, you get the full sound of what the pickup is trying to do... I mean EVH has been doing that for years, among many other major shredders... there has to be a good reason for it :-D


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## DropDizzle

Is there a difference between a 250k ALPHA pot and a 250k CTS pot?


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## maxz

MF_Kitten said:


> does that mean that you can change the K value of a pot?


no you cant change the ohms value/just change the pot to higher value . unhook um use a kill switch total output total tone/get rid of tone too. too get higher value with existing pots wire vol.&tone(make into a 2nd a vol.) in series more volume!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


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## maxz

try 1meg pots if u have to hav a vol. they have 2meg now even better/unhook the tone 4 more output-or turn it into another vol.run in series more gain. i do use pots;2 cut either coil on a humbucker pu most always the neck pu 3 difnt sounds 1 pu!
it takes 2 pots or more to work- if your good youll figure it out~!


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## guitarneeraj

maxz said:


> no you cant change the ohms value/just change the pot to higher value . unhook um use a kill switch total output total tone/get rid of tone too. too get higher value with existing pots wire vol.&tone(make into a 2nd a vol.) in series more volume!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



How does changing say, a 250K pot to 500K give more volume??! You're stating something wrong, my friend. The output from your pickup will always remain constant, you cannot increase it unless with some active circuit elements. So if you wire 2 pots in series, you have more resistance to ground and so the volume will of course decrease. Imagine the 500K pot as being two 250K pots. Hence, a 500K pot, in comparison to 250K, would mean that beyond 250Kohm resistance on the 500K pot (i.e. max position on the 250k) , you get an added 250K resistance to ground, which is (partly) what prevents high frequencies from getting lost; and also why you get more attenuation on your signal, than when using a 250K pot.

In essence, a "volume" pot (passive) is not like a "gain" control, it's more like an attenuation control. At Volume = max, you get the full output from the pickup, as you roll it down, the output gets attenuated because some current from the pickup's output is drawn by the resistance of the potentiometer.



maxz said:


> try 1meg pots if u have to hav a vol. they have 2meg now even better/unhook the tone 4 more output-or turn it into another vol.run in series more gain. i do use pots;2 cut either coil on a humbucker pu most always the neck pu 3 difnt sounds 1 pu!
> it takes 2 pots or more to work- if your good youll figure it out~!



This is a dubious statement my friend. Potentiometers are after all resistors, only variable. Therefore, same laws which apply for resistors, also apply for potentiometers. If you have higher value pots, they will be noisy like a futhermocker. This is because, the higher the resistance, the more the thermal noise.

However, I do agree that the tone pots on guitars are pretty useless with the stock ceramic disc capacitors that are put in there. Anyone wanting to get a richer and more intuitive control should definitely think about firstly replacing the tone pot with an Audio (logarithmic) Taper potentiometer, and then experimenting with different types (yes, types) of capacitors. A 0.047uF ceramic capacitor will sound vastly different from a Sprague orange drop, in a tone control. Please refer the previous YT link I posted for demos from the same guy about how different types of capacitors sound.

I really hope this thread does not spread misinformation. If you have any doubts about pots, don't hesitate to ask!! I'm sure there are a lot of knowledgeable people on ss.org who will be willing to answer!


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## guitarneeraj

DropDizzle said:


> Is there a difference between a 250k ALPHA pot and a 250k CTS pot?



Only in the quality!!


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## DropDizzle

guitarneeraj said:


> Only in the quality!!



care to explain to a newb? ^^


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## guitarneeraj

Okay, for example, let's take the CTS 450 Series pots (i.e. the standard ones which are available on eBay/AllParts), and ALPHA 16mm pots. 

The minimum tolerance for CTS pots can be upto +/-10%, whereas for ALPHA pots, it is +/-20% by default. Of course as the tolerance decreases the price of the part will increase, since we're talking precision here. To be noted is that cheapest CTS pots have, by default +/-30% tolerance. The tolerance is basically, the variation in the total resistance of the pot. So if you buy a 250K pot, it will never show exactly 250.0K ohm, on a multimeter. The tolerance means that the resistance value can vary anywhere between +/- X% of the specified value. 
So.... for 250K with 10% tolerance, the actual value can be anywhere between 225K to 275K, but with 20% tolerance, the actual value can be anywhere between 200K to 300K!!! 

With CTS pots, the power rating is also better than ALPHA. Another point to consider, is the robustness. In my opinion, CTS pots are better in terms of manufacturing quality. You might also want to look at BOURNS, which also makes superb quality potentiometers. All in all, it's always a trade off between precision, manufacturing quality and price. You will find that ALPHA pots are mostly present in Ibanez guitars as stock pots. A good benchmark, in my opinion, is to consider everything Ibanez uses stock (in hardware i.e. pickups, electronics, tuners) as complete crap. 

Hope this helps!


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## GorillaSalsa

Say I wanted to use no potentiometers with my guitar, how would this effect things? The OP says that more resistance = brighter tone, but I would think that zero resistance would mean a fuller tone, yes?

EDIT: whoops, sorry about that! vvvvvvvv


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## guitarneeraj

GorillaSalsa said:


> Say I wanted to use no potentiometers with my guitar, how would this effect things? The OP says that more resistance = brighter tone, but I would think that zero resistance would mean a fuller tone, yes?



Please read all the replies in this thread, user Cannibalbritney describes and has implemented the kind of wiring you mention..


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## Suitable

^ You noted 2 types of CTS pots, +/-30% and 10%. How do you work out which is which? Also for going 1 vol and 1 tone, 500k A pots would be best? And what brand/type caps are best? You said ceramic caps are shit, what are the other made from? Im about to change all the electronics in some of my guitars, so want to do it right the first time round.


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## guitarneeraj

Suitable said:


> ^ You noted 2 types of CTS pots, +/-30% and 10%. How do you work out which is which?



Well, you take a multimeter, measure the resistance and check which tolerance bracket it's in.. 

Just checked the CTS website, they have a new series called 450G, the "Guitar Series". 

http://www.ctscorp.com/components/Datasheets/450g.pdf

This datasheet clearly gives the part number you'd need to specify if ordering 10% or 20% whichever the case may be.



Suitable said:


> Also for going 1 vol and 1 tone, 500k A pots would be best?



For volume use an audio taper pot for sure. For Tone I would advise using linear taper, not many people like the feel of an audio taper pot for the Tone control. 

500k pots are not the "best", you can even use lower values like 250k or 100k(if you want lesser noise but can deal with a slightly darker tone). Depends what your goal is. 



Suitable said:


> And what brand/type caps are best? You said ceramic caps are shit, what are the other made from? Im about to change all the electronics in some of my guitars, so want to do it right the first time round.



There are many types of capacitors, depending on the material used for the dielectric. Polystyrene are the best for low values (upto 0.01MFD or so); beyond that they get bigger in size so then you use stacked metal film or metal film.


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## Kingarchetheros

does that mean that you can change the K value of a pot?


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## conjurer_of_riffs

Lets say that I have one volume and one tone. If I change from passive to active pickups or vice versa, will I have to change the volume and the tone pots or just the volume? Thanks in advance.


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## DaPsyCho

conjurer_of_riffs said:


> Lets say that I have one volume and one tone. If I change from passive to active pickups or vice versa, will I have to change the volume and the tone pots or just the volume? Thanks in advance.



Yes you will. Active pickups are electromagnets and hence require different amount of resistance to give out a "guitar" sound.

Basically, the lower rated the pots (the lower K it has), the more warmer/duller tone u get. Passive pickups aren't very trebly, at least not as much as actives, hence they have higher rated pots, to give them more "punch" or treble and make them sound like a guitar should (the balance between bass, mids, and treble).

But Active Pickups have much more treble, and not as much bass, which is why they almost never sound "muddy" and sound "crisp". But the thing is this extra treble needs to be balanced out, to give out a sound that is pleasing and more guitar-like. Hence to cut the treble, Actives use low rated pots usually 20-25K. U can see the difference between the normal 500 for a passive and a 25 for an active, and thus using a 500K pot on actives will sound quite terrible and m8 make ur ears bleed due to the insane amount of treble.


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## guitarneeraj

DaPsyCho said:


> Yes you will. Active pickups are electromagnets and hence require different amount of resistance to give out a "guitar" sound.



First off, no pickup is an "electromagnet". Electromagnets are the opposite of guitar pickups, look up the E-Bow.



DaPsyCho said:


> Basically, the lower rated the pots (the lower K it has), the more warmer/duller tone u get. Passive pickups aren't very trebly, at least not as much as actives, hence they have higher rated pots, to give them more "punch" or treble and make them sound like a guitar should (the balance between bass, mids, and treble).
> 
> But Active Pickups have much more treble, and not as much bass, which is why they almost never sound "muddy" and sound "crisp". But the thing is this extra treble needs to be balanced out, to give out a sound that is pleasing and more guitar-like. Hence to cut the treble, Actives use low rated pots usually 20-25K. U can see the difference between the normal 500 for a passive and a 25 for an active, and thus using a 500K pot on actives will sound quite terrible and m8 make ur ears bleed due to the insane amount of treble.



I won't get into the details of how and why, the bottom line IS this -> Active pickups = Passive pickups + integrated preamp (cast together in epoxy). The distinct character of active pickups depends on how the preamp is designed (almost always an op-amp in differential configuration) and then the opamp chip itself and preamp circuitry contribute to the tone.

With active pickups, it's possible to use ANY (yes, ANY) value for the volume and tone, however the lower limit depends only on the output impedance of the preamp circuit. An opamp's output impedance is very low, but for instance, EMG designs their preamp such a way that the output impedance is about 10k ohm. Which is why they recommend using 25k pots (Read about loading of a voltage source so you understand why you cannot theoretically go below 25k, although it IS possible). You can very well use values above this recommended value, but not BELOW. 25k is recommended by EMG as the thermal noise will be the least in a 25k pot.


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## Omer45615

Thanks for sharing.


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## TRENCHLORD

Bumping for advice.

Getting ready to install an old x2n (been in box for 15yrs lol) and a brand new d'activator-x neck into my Guerilla w/basswood wings.
I love the emgs in mahogany bodied guitars but am just wanting a different feel with this one, and that x2n is calling out to be used, I can really hear it .

My questions are;

Since I'd like to go toneless and be one volume only w/3-way switch, would I be better using a 1meg volume or 500k?

Is there any distinguishable noise increase going up to 1meg with an x2n or any super high output pickup?

Would there be any advantage to using two volumes, and if so what rating for them?

My goal is to get as much attack and jolt possible from the bridge, and honestly the neck's performance is secondary to that.
It's a thrash/DM guitar only so the neck will be for leads only (blended and separate).
I'm not that concerned with being too bright because my amp has treble and presence knobs . 
If a 1meg or pair of them won't really help with the jolt/thud and they increase thermal noise then maybe it's not worth it. /?

For any advice THANKS


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## TRENCHLORD

^^^^^

emailed dimarzio asking this, and they said;

In a one volume only guitar there would be no appreciable difference between using a 1meg or a standard 500k if you are using a high gain amp.

Anyone tried this and disagree?


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## guitarneeraj

TRENCHLORD said:


> ^^^^^
> 
> emailed dimarzio asking this, and they said;
> 
> In a one volume only guitar there would be no appreciable difference between using a 1meg or a standard 500k if you are using a high gain amp.
> 
> Anyone tried this and disagree?



That is correct.


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## Omer45615

Omer45615 said:


> Thanks for sharing.









http://plagiarismchecker.mobi/


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## cardinal

I hate replacing pots. Just thought I'd mention that after having to replace a failed volume pot with like five different wires grounded to the back of it.


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## AntonyMarsh

Hello...I need to recreate a Ni1000 temperature sensor, successfully a variable resistor that changes by approx. 5.5Ohms/°C. This is effortlessly accomplished utilizing a manual exactness turn potentiometer of reasonable range, however I might want an advanced strategy as pots are cumbersome and keep an eye on occupy a great deal of room and wiring and so on.


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## spudmunkey

I don't think so, but has anyone mentioned manufacturing tolerances? I've seen posts from folks elsewhere, where they measured pots from different manufacturers (based on the pots they had on hand). Manufacturing tolerences for some were as high as 10-15%, if I remember right. That could be a pratty large swing, from pot to pot, from the same brand. So a 10% swing could turn a 500 into a 450 or a 550. It's not like it's turning a 500 to a 250, but is it something one might consider at all?


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## KenA

Suppose a 1 pot guitar of 500k and just 1 humbucker. Considering not to use a push/pull pot and also not to split the hb coils, what are the mods I can do to the system? I mean add Caps into which pot's lugs combinations?


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