# What pots and capacitors? And is phase switching good?



## HeinrichDerp (Apr 29, 2014)

Alright, so I am currently working on a sort of vintage-vibe Les Paul thing, and I'm onto the electronic portion of the build. I think I've settled on the GFS Surf 90's (http://www.guitarfetish.com/GFS-Surf-90-Alnico-II-Rockabilly-Pickups_c_259.html) in black and chrome, but I am wondering what pots (500 or 250) you guys recommend, and also what kind of capacitors you guys recommend. Lastly, is adding phase switching a good idea, since I'm experimenting with tones and I'm wondering how it will effect everything. Thanks!


----------



## greco (Jul 15, 2007)

There will likely be several opinions regarding your questions...so get ready...LOL

TONE POTS:
I would always use 500K ohm Audio taper pots for TONE pots. This concept came up recently in a thread and made a lot of sense to me due to the range/sweep for TONE.


VOLUME POTS:
I like 250K ohm Audio taper pots for single coils and for humbuckers for VOLUME pots. 
However, many prefer 500K pots for humbucker and 250K pots for single coils.
I have tried 500K pots with single coils and didn't like the sound.

There are other pots available for very specific applications (e.g., pull for coil switching, etc.)
Some of the typical and reliable brands are: CTS, Bourns, Alpha

CAPACITORS: 

The typical electronic values used are 0.01 uf, 0.022 uf, 0.033 uf and 0.047 uf (uf = microfarads)

The monetary values are form less than about $2.00 ea. to "the sky is the limit".
However, I am sure many will agree that Sprague "orange drop" caps are a popular/reasonable choice

Here is a good article about tone caps: http://proguitarshop.com/andyscorner/ez-mods-guitar-tone-caps

WARNING: You could end up reading about tone caps for years. 

Phase switching: Sorry, I can't help you with this.

BTW...I tried GFS pickups in the past...I wasn't very impressed.

I hope some of this was helpful.

Cheers

Dave


----------



## mhammer (Nov 30, 2007)

Many of the choices to be debated concern "strategic treble loss". The amount of treble to be _deliberately_ lost (or retained) will depend not only on your pickups, but your amp, your preferred amp settings, how you use pedals, cables, and your personal usage of on-board knobs....for starters.

In a very general sense, higher-value volume and tone pots will bleed _less_ treble, when they are set to full up. For this reason, they are preferred by those who use pickups with less treble to start with, and less frequently used by those playing pickups that they perceive as having _too much _treble to start with. However, as I've noted on many an occasion, the moment you start to turn your volume pot down a bit, the treble-retention advantage is lost. Some players tend to leave their knobs up full, and rarely work them, while others are twirling them incessantly. If you happen to be of the second type, then pot-value choice may be moot, and other means will be more critical in to achieving the tone you want.

Then there are always players like Jeff Beck, who cranks his amp, and purposely keeps the guitar volume-knob down to load the signal in strategic fashion, and bring it up to elicit not only more volume but more brightness from the amp when he wants. That is, he is not working the volume pot to dictate the sound of the guitar as much as using it to dictate the sound of the amp.

Tone cap values depend on the tone one is aiming for. I am a loud complainer when it comes to the "tradition" of using the same cap values for neck and bridge pickups. It has never made any sense to me, whatsoever. The higher the cap value, the duller the resulting tone will be when you roll the tone back. If you can find me a player that deliberately selects their _bridge_ pickup to achieve a dull tone, I will hire you to find the body of Jimmy Hoffa. So, if you have dual vol/tone controls, give serious consideration to using a tone cap for the bridge that is half the value of whatever you use for the neck. If you like .022uf for the neck, use .01 for the bridge. If you go with .047 for the neck, go with .022 for the bridge. The smaller value will allow you to "round off" the tone of the bridge pickup, as opposed to making it duller-sounding.

One of the things I like to do with guitars that have a Telecaster-like complement of controls is to make the tone control bi-directional. I use a 1M linear pot, to make each direction roughly equivalent from the mid-point, and use a smaller tone cap in one direction, and larger one in the other. At mid-rotation, the tone control has minimal effect (i.e., full bright). In one direction it does the "rounding" thing, and in the other it does the dulling thing.

Whatever the case, and value, pot *taper* will be important in yielding what you find as useful pots. The volume pot needs to be audio/log taper. Opinions vary on what delivers better "dialability" for tone pots. Happily, the taper of tone pots can be played with by adding assorted parallel resistances (see here: http://www.geofex.com/article_folders/potsecrets/potscret.htm ), although you generally need to start out with a higher value than you wish to end up with.


----------



## J S Moore (Feb 18, 2006)

mhammer said:


> Tone cap values depend on the tone one is aiming for. I am a loud complainer when it comes to the "tradition" of using the same cap values for neck and bridge pickups. It has never made any sense to me, whatsoever. The higher the cap value, the duller the resulting tone will be when you roll the tone back. If you can find me a player that deliberately selects their _bridge_ pickup to achieve a dull tone, I will hire you to find the body of Jimmy Hoffa. So, if you have dual vol/tone controls, *give serious consideration to using a tone cap for the bridge that is half the value of whatever you use for the neck.* If you like .022uf for the neck, use .01 for the bridge. If you go with .047 for the neck, go with .022 for the bridge. The smaller value will allow you to "round off" the tone of the bridge pickup, as opposed to making it duller-sounding.
> 
> One of the things I like to do with guitars that have a Telecaster-like complement of controls is to make the tone control bi-directional. I use a 1M linear pot, to make each direction roughly equivalent from the mid-point, and use a smaller tone cap in one direction, and larger one in the other. At mid-rotation, the tone control has minimal effect (i.e., full bright). In one direction it does the "rounding" thing, and in the other it does the dulling thing.


I will have to try that part in bold. I use .015 in the neck so it doesn't get too dark but never thought about it for the bridge. I'm rarely below 6 or 7 on the bridge tone but I'll bet that will make it useful all the way.

I actually don't have a tone pot on my Tele, I have a blend pot. If I want to darken up the bridge I roll in a little neck and vice versa.


----------



## blam (Feb 18, 2011)

Interesting..... 

I'm a 0.022 guy in my humbucker guitars and been thinking of going 0.015 in the neck since rolling it back is way too dark. 

In my tele I use 0.047 which I'm happy with. Not sure what I'm doing with my strat yet. 

As for pots, 500 for my humbuckers. My Tele has a 250 and my strat I'm going 250 as well


----------



## mhammer (Nov 30, 2007)

J S Moore said:


> I will have to try that part in bold. I use .015 in the neck so it doesn't get too dark but never thought about it for the bridge. I'm rarely below 6 or 7 on the bridge tone but I'll bet that will make it useful all the way.
> 
> I actually don't have a tone pot on my Tele, I have a blend pot. If I want to darken up the bridge I roll in a little neck and vice versa.


It's the sheer dead weight of precedence, my friend.  It gets in the way of our thinking in many ways.


----------



## mhammer (Nov 30, 2007)

The OP asked about phase-switching, and none of us have really addressed it.

Reversing the phase of a pickup in a 2-pickup instrument will provide a very different sort of sound, and expand your tonal palette. Not everybody finds it useful, though. The degree of cancellation is a function of the degree of overlap between what each pickup senses. If they are rather different from each other, there will be less volume drop because the two pickups will cancel each other out less. If they are fairly similar in their output tone and what they sense, you'll get a noticeable volume drop.

Phase reversal in an Albert Collins-style Tele (SC in the bridge, and HB by the neck) would yield better outcomes than phase-reversal in an SG, where the two HBs are so close together that they have very similar sounds.

The tone of phase-reversal in most instances can be likened to the sound of T-Bone Walker or Johnny Guitar Watson; a thin reedy tone. It's great for rhythm playing but less great for any sort of higher-energy strumming or picking.

I would imagine in many instances, some players may prefer to implement coil cancellation _instead of _phase-reversal. The change in tone and volume level is not quite as abrupt, and the shift in resonances is musically useful. But, since you're using the GFS Dynasonic-inspired pickups, coil cancellation is out of the picture, since there is no second coil to cancel.

I'm wondering whether some sort of implementation whereby phase-reversal is accompanied by the insertion of a resistor, or cap, or both, in series with one of the pickups, would result in less intrusive cancellation. I know the Jerry Donahue model Telecaster uses only 2 pickups, and inserts a cap in series with the neck PU for one of the 5 selector settings to get a respectable Strat "cluck". If you're going to install a toggle or push-pull switch, maybe a 3-way toggle that inserts a cap n series with one or the other pickup would be a productive, and viable option. If the neck pickup has some of the bass rolled off, that will breathe some new life into the N+B setting.


----------



## JHarasym (Mar 27, 2007)

mhammer said:


> ... some players may prefer to implement coil cancellation...


Mark, would you care to explain this a bit further (or post a link)? 
I googled it and didn't see anything useful.
Is this cutting out one of a humbucker's coils?


----------



## mhammer (Nov 30, 2007)

Yep. I suppose it really ought to be called coil-_bypassing_ since it typically involves placing a straight-wire connection in parallel with one of the coils, such that the coil being paralleled is effectively out of the picture and not contributing any signal. I suppose one could call it "cancellation", but in a discourse about phase-reversal, that's a bit of a misdirection, since it suggests that one of the coils on a pickup is somehow being cancelled by the actions of another pickup, and that's not at all what is intended. My bad.

In a recent issue of Guitar Player (the one with the Fishman pickups on the cover), Craig Anderton had a nice little article on the difference between coil-tapping, coil-cancelling, and a few other things that are often confused.


----------



## MReilander (Mar 16, 2011)

> Yep. I suppose it really ought to be called coil-bypassing since it typically involves placing a straight-wire connection in parallel with one of the coils, such that the coil being paralleled is effectively out of the picture and not contributing any signal. I suppose one could call it "cancellation", but in a discourse about phase-reversal, that's a bit of a misdirection, since it suggests that one of the coils on a pickup is somehow being cancelled by the actions of another pickup, and that's not at all what is intended. My bad.
> 
> In a recent issue of Guitar Player (the one with the Fishman pickups on the cover), Craig Anderton had a nice little article on the difference between coil-tapping, coil-cancelling, and a few other things that are often confused.


The proper term, which I rarely hear in the guitar world, is a coil shunt or shunting a coil. You are creating a direct path to hot or ground (usually ground) prior to the coil you would like to eliminate. This eliminates that coil from the circuit. The more common term that I see to describe this is a _coil split_.

As for your explanation on strategic treble loss... I couldn't have said it better myself.


----------



## mercimek (Jun 24, 2014)

@HeinrichDerp: Hi, the phase switching is the good idea as it eliminates the problem like early and tinny feedback, unbalanced sounds and the sound cancellation on some notes and that are mainly occurs due to the out of phase signals.

pcb and assembly


----------

