23 August 2012

Howlings, whistlings: the Microphonics' Monster


You plug your preferred guitar on your preferred amp and, when going up on your gain level, you start to hear microphonics issues. Whistles, howlings, an uncontrollable feedback that ruins your tone and pains your ears. WTF?. Everything sounded fine yesterday!. What's happening?.

Microphonics is one of the big Monsters that eat our tone and ruin our performance and, they can happen everywhere in our gear but, WHY our gear goes microphonics?.

I want to share with you a recent experience, among other well known issues that I had in the past. I hope, it could help you to defeat your own monster.

Why do we have microphonics?

To make a large history short, we have microphonics because some device in our signal path has metallic parts that can freely vibrate. The sound pressure coming from our speaker makes that parts to vibrate. Such a vibration is being catch by our pickups, amplified by our amp and sent back by the speaker. The metallic part vibrates even more, being catch by our pickups, amplified again and sent back again at higher volume, what increases the vibration and... well... you get the picture. This is an eternal feedback that goes every time louder and that creates some howling or whistlings in the resonance frequency of that vibration.

Where do we have microphonics?

Mmmh... free vibrating metallic parts, do you mean?. I have not such a thing on my chain!.
Well, dude, you are damn wrong!.
Let me show you some examples and be prepared for some surprises.

Cords and Patch Cables

Cords and patch cables with solid core conductor have no microphonics issues but, since they are in fact a continuous bar of copper, they aren't flexible enough and, they are not normally used for guitar cables or patch cables. Cables with multiple thin copper strands are being used, instead.

High end cables (not necessarily, super expensive cables) are well built and, even that they are slightly prone to microphonics issues, they stand in a good position.
But, cheap cables, with cooper strands and a cooper mall for the cable' shield have a lot of little metallic parts that can freely vibrate!.

While your guitar is plugged on your amp, and your high gain stuff cooking the amp, create a loop in a short portion of the cable and, firmly grave the two extremes of the loop in your hand. With the other hand, beat the cable with a solid piece of whatever you have around (the bridge's tremolo, by example) on any part of the loop. If you clearly hear the beat sounding thru your speakers. You have a microphonics cable.
You can test on that way even your patch cables.

The only cable with multiple cooper strands on its core that I know is trying to reduce that micro-collisions between strands is The Forte, by Evidence Audio, who is treating every strand individually with a protective coat that avoid the direct contact metal against metal.


Loose jacks are often a source of microphonics (among other) issues. Review your jacks and be sure their nuts and washes are strongly screwed and the jack seems tightened.
Jacks are everywhere on your gear: pedals, amps, guitars...

A warning also about cheap jacks. If their internal plates move freely, they can become microphonics. Use quality jacks, as the swiftcraft's ones, by example.

Take also into account cheap jack plugs. If the internal parts of the plug can freely move, they can be microphonics. Once again, try to use quality jacks, as Neutrik's ones, by example.


Well, at least that the pedal was wired with solid core wires (what I seriously doubt, even on the expensive ones), they are using multi-stranded core wires and... we already discussed that, right?.
If your pedal goes microphonics because of its wiring... there is really few you can do, apart of try to reduce such a feedback by using a Noise Gate on your chain.

Pedals have also jacks and, we already talked about this.

Pedals have also mechanical switches, with movable parts. If the switch isn't of quality, it can be another source of microphonic issues.

If the pedal goes microphonics, check first if there is inside something that needs to be tightened: as the screws of the circuit, the jacks, whatever and, if everything is tight then... consider to remove such a pedal from your chain or use a Noise Gate (if it works).

Switching systems, with lots of loops, have lot of wire and lots of jacks to review!.


Guitars are usually the main source of microphonics issues.
We have wires inside (that can be microphonics).
We have the guitar's jack.
We have a lot of movable metallic parts, even than some are more critical than others.
And, we have pickups. Pickups are the main source of microphonics issues on a guitar.

A pickup has one or more magnetic coils, wrapped with long lengths of cooper wires, thin as a human hair.
To avoid the free movement of those long turns of a single wire, pickups are nowadays Wax Potted the most of times. But, we aware that most of the Antiquity, Vintage-right, or whatever name they have to make an exact reproduction of a vintage model, are usually un-potted and then, very prone to microphonics, once gain reaches some level.
Even, if they are potted, sometimes some pickup isn't correctly potted and, becomes microphonics.

Then we have some pickups with a metallic base plate. This metallic base plate is being used for two things: to bound back the magnetic field generated by the pickup, what increases the middles and the punch and, to serve as the bridge ground (since pickup' screws are in contact with the plate and the metallic bridge (in Telecasters).

We have pickups that are being mounted with metallic springs, those can vibrate, as well. Some pickups' makers, as Seymour Duncan, are including surgery tubes instead of metallic springs for pickups' screws, what mitigates vibrations of the screws themselves, which can be transmitted to the plate and catch by the pickup and... well... well... you know the history.

And we have bridge plates, as in the Telecasters, that can be prone to little vibrations and become microphonics.

I was working on a Telecaster of a friend of mine, wiring it. When I went to test the Telecaster, as soon as I switched on bridge pickup, the amp started howling and screaming as a crazy. I've change every electronics parts with new brand ones: pots, switches, jack, caps, wires... everything new brand!. And the howling didn't disappeared.
I was stuck for a long while, running out of ideas. Checking the wiring with a multimeter, with the logic saying that the design and implementation were absolutely right and, trying everything it came to mind without success.

Desperate, I've searched on Internet and found that this is a common issue with Telecaster bridge's pickups. Telecasters with steel bridges form part of the magnetic field of the pickup itself. The plate under the pickup increases the strength of such a field, also so, at the end, you have some kind of big pickup very sensitive to anything that moves around a big magnetic field.

Well, in those cases, there are a lot of things to test, increasing the difficulty:

  1. To firmly glue the plate to the pickup's base. I've used Loctite for that.
  2. To substitute springs with surgery tube or any proper plastic, vinile or rubber tube.
  3. To use screws with higher gauge to fix the bridge's metallic plate to guitar's body. Any loose screw there and your plate will vibrate and create feedback.
  4. To wax pot your pickup
  5. To drill to additional screws in the front of your bridge's plate to force it to remain over the body without additional vibration.
In my case, I've totally fixed the issue gluing the base plate to the pickup, substituting the springs with a plastic tube on every pickup's adjustment screw and, substituting the 4 screws that secure the plate against the body with 4 new screws with an slight bigger gauge.
That fixed the issue instantaneously and, now, my friend can enjoy his loved Tele.


We have wires also. The most of well built amps will use solid core wires to wire the different components but, they can use multi-strand wires so...
We have jacks, also.

But, honestly, the most of microphonics issues that occur in an amp are related to tubes and, specially to the very first preamp tube (usually named V1).

The tube has a lot of metallic parts in its structure, inside the bottle. The constant vibration that are getting from the speaker itself and, some degradation due to the use, can make some little parts loose and then, microphonics issues attack us again.

Microphonics in amps are usually solved just swapping the first tube with a low-microphonics high quality tube. Power tubes can go bad also, after some time so, if your work on preamp solves nothing, maybe it's time to swap your power tubes.

As ever, review jacks also and, any other potentially movable metallic part inside.


Once you have a microphonics issue, you need to isolate the source first. Use your guitar directly plugged to your amp and, try to determine if it's the amp, the guitar or the cable what is microphonics (check with other guitar and other amp, check a loop in the cable as explained above...).
If it's the amp, try to swap first V1.
If it's the guitar, your pickups are probably the source of the issue.
If it's the cable, try another cable.
If your amp hasn't a gain channel, try then with your gainer pedal between your guitar and amp.

Usually, tubes, pickups or cables are the common source but, be prepared for any other source, as we have explained above. Sometimes, a microphonics issue can take a long time to be chased but, at least, you now where to search now.

11 August 2012

Wiring DIY - Part 10

Other Modules

Following modules, aren't directly related to just a coil or pickup but, they are more generic.

ArtieToo's Coil Swap

Once more, Artie came with a nice wiring that allows to create some virtual humbuckers, giving more combinations to your axe. Interesting idea. See the following diagram:

Each pickup's hot is routed to the right place (the volume pot or the selector switch, etc.).
When the switch is off, both humbuckers work on standard humbucking mode but, when the switch is toggled on, both humbuckers interchange their coils so, we are creating two new virtual humbuckers where the screw coil belongs to pickup A and the slug coil to pickup B and, where the screw coil belongs to B and slug to A.
Because of the distance between coils (one from neck and one from bridge pickup), we are having more openness in the sound.
This mod works better when each pickup has unmatched coils (not twin coils), because in that way, the differences between the two real humbuckers and the two virtual humbuckers are more distinguishable.
We just need a DPDT on/on switch here and, therefore, can be implemented with a pull/push switch.

Kill Switch

This is the typical button that someone press, intermittently to momentary interrupt the sound. Very liked by metalheads, it can be install on any axe, including active pickups based axes.

For this, we need a momentary on switch, so some sort of DPDT on/[on] switch.
The switch will toggle to kill switch mode while we maintain the pressure over the button. Those kind of switches are very usual in a press-button format and, there are some models that are small enough to be installed in any axe.
But, for sure, you can do it also with any regular DPDT on/on but, in that case, you will need to manually toggle on/off the switch.


A way to add some more combos to your Stratocaster or Telecaster is to install a bridge-on switch. When this switch is on, the bridge pickup will be added to any of the rest positions doesn't having the bridge pickup active by default.

When the switch is "off", the bridge's positive wire is routed the the normal lug on the selector switch but, when the switch is "on", the bridge's positive wire is linked to the regular output (from common lug) of the selector. This will add the bridge pickup in parallel to the three first positions of your strato so, you will have:

Neck in parallel with Bridge
Neck in parallel with Middle and Bridge
Middle in parallel with Bridge

As new-brand combos.

This mod can be implemented with a simple SPDT on/on switch or one pole of a DPDT on/on so, you can use a discrete pull/push pot for this.

Volume bypass

This mod allows you to bypass the volume control. This gives you an slight boost on the overall volume and, the sound is just a bit darker. It also allows you to immediately pass from a moderate volume level (by example, volume pot at 7) to full-throttle, as soon as you activate the switch and, to come back to your original volume once you are done with the full-throttle sound.
For that people that loves to control the amount of distortion of his amp just rolling off the volume pot, this can be useful to instantaneously swap from light drive to distortion at any moment and, come back to light drive exactly on the same volume pot position he has!.

We need any DPDT on/on switch, therefore, you can use any pull/push pot for this.
The hot input (from the pickup or the selector switch) is usually routed to the volume input but, when the switch is on, it's routed to the jack's output, instead.

For sure, you can use same trick to bypass everything, including tone control.

Stacked volume and Tone

Well, to include some interesting changes to your guitar maybe leads you to sacrifice one pot (and substitute it with a rotary switch or a toggle switch, by example). This sacrificed pot is often a tone pot. Even that most of people is working with its tone pot(s) at full all the time. But, if you want that tone pot come back after sacrificing its natural place, we have stacked pots to do that.
With a stacked pot, we can have volume and tone in a single pot. Usually, the edge of the pot has two different shafts, the lower one corresponds to the upper pot and the upper one corresponds to the lower pot. Those will need special knobs.
You can have two pots with different resistance values stacked together.

Look at this picture:

On the picture, the upper pot is the volume pot, while the lower pot is the tone pot. They are wired in modern way but, remember that you can always wire them in whichever of the 4 ways that we already described.

Be sure to don't confuse a stacked pot with a blend pot. Blend pots, usually have just one shaft that rolls to the upper pot in a half and that rolls to the lower pot on the other half of its rotation and, they usually have a center detention spot.

More mods?

We have described the most usual mods and even, some more but, as far as the imagination goes, the mods go so, be sure we aren't describing all possible mods. By example, you can select the mix of a pair of pickups with a blender pot, you can mix a piezo system with your passive pickups or, you can mix your active with passive pickups, etc.
I am always seen new ideas coming up when someone is ordering some wiring design to me (and I love it!).

End of Wiring DIY parts

Respect of describing the basic building blocks for our diagrams, we are done.
On future articles, I will introduce some wiring design and will discuss about what's special on it.
On a future article, I will describe the right way to solder a wiring design, as well as how to shield your guitar.
Those commented wiring will be delivered from time to time, with no planned schedule.
I am quite sure you have here information enough to start the most common modifications and, I hope you will appreciate it.

08 August 2012

Wiring DIY - Part 09

Humbucker modules

Even that we are naming this modules as humbucker related, you should take into account that those apply to any combination of two coils or two pickups.
Remember than, even that the output negative wire is shown as grounded in all these schemes, it can be prolonged out of this module to be used in further modules.


This will be used to toggle between parallel and series arrangement of pickups or coils. See this picture:

The first scheme corresponds to the usual way to select between series and parallel. There is just a single signal output and, it's mainly used to select series/parallel within a humbucker.

The second scheme corresponds to a way to connect two pickups in series or parallel, while sending it's outputs to the corresponding pickups' selector switch.
When they are in parallel, HOT1 corresponds to output signal of the upper coil (or pickup)  and, HOT 2 corresponds to the output signal of the lower coil (or pickup). When they are in series, both hots (HOT1 and HOT2) have the same signal output, that is, both coils (or pickups) in series.
This is a tricky way to avoid some blackouts on selector switch when putting two pickups in series.

Splitter switch

This kind of wiring will allow us to choose one of the coils of a certain humbucker but, remember, it can be used to select one or other pickup, as well. Look at this picture:

The first schema is being used to split to inner coil (the one that points to the neck), in this case, the slug coil.

The second schema is being used to split to outer coil (the one that points to the bridge), in this case, the screw coil. Remember our previous discussion about this way of selecting the screw coil. It can have side effects but, the most of times it works.

First and second schemes can be implemented by using just a SPDT on/on switch but, for sure, you can always just wire one row of a DPDT on/on switch (as a pull/push pot, by example).

The third schema corresponds to a switch that will select inner coil / humbucker / outer coil.
This needs a SPDT on/OFF/on or a DPDT  on/OFF/on and, it will modify the aspect of your guitar.
The good thing is that allows you to select any of the pickups of a humbucker or the native humbucker mode (on middle position).

If you wanted the 4 fundamental tones of a humbucker (split-inner, split-outer, coils in parallel and coils in series) you will need at least a 2 poles and 4 throws switch, as the Telecaster 4-way or any DP4T you can find, including rotary switches. See the picture below:

Both switches are doing the same:

Position 1: humbucker (coils in series)
Position 2: coils in parallel
Position 3: screw coil
Position 4: slug coil

But, the potential issue that we described with the split to screw coil option is still there. To make it bullet-proof, we should need a 4P4T switch and, this is usually only available as a rotary switch.

We have still one more way to select the 4 foundational tones of a humbucker by using a couple of DPDT on/on switches (that is, two pull/pushes, by example). Look at this picture:

This was designed by user ArtieToo, that you can find on Seymour Duncan's forum. A real wizard of electronics and, a wise and kind man. I've learnt everything from him.
The original design was made by Frank Falbo of Seymour Duncan' staff but, Artie improved it to reduce any potential side effect. First time I saw this tricky wiring, I was absolutely shocked.

To get the 4 positions you need to work on both switches.
When both are down, you have coils in series (standard humbucker).
When both are up, you have coils in parallel.
When one is down and the other up, you have the two splits.
Very useful, if you don't like to change your guitar's appearance.

On next part, we are going to talk about other useful things, that are more general or that include a couple of humbuckers, by example. We will discuss the Artie's Coil Swap switch, the kill-switch, the bridge-on switch, the bypass switch, etc.

Pedals: Wampler Sovereign


To my taste, Wampler makes the most interesting gain pedals but, Wampler is mainly doing amp-in-a-box type of pedals. That's nice if what you are looking for is just that and, certainly, I love the tone of the Pinnacle and SLOstortion and, I will probably love the Triple Wreck but, what I wanted is a pedal that I can tweak to my taste, without being an amp-in-a-box distortion type.

Thanks to the request from Guitar Center, Brian Wampler did a versatile distortion unit and named it the Sovereign. Unfortunately, to buy this pedal is possible only in two Musical Stores in USA. You cannot even buy it directly to Wampler. Importation and transport fees are too much to order this from Europe so, even wanting it to death, I decided to wait until the Sovereign was released for European Stores.
But, I had good luck, at the end!. A friend of mine was on Holidays on NY and asked me if I wanted something from there. Sure... I want a Sovereign pedal!. And, he went to GC and bring me that little beast.

The half hour that I spent the very first day he bring it to me, I was smiling like a mad. Finally, a good and modern distortion unit that can take the place to the RAT.


On the line of the rest of Wampler's pedals. Comes in a discrete white carton box, with some sticker on the front, with a picture of the pedal and Wampler's logo. The pedal comes inside a fabric bag and wrapped on bubble plastic. Inside the box, as ever, a single-sheet "user's manual", one sticker with Wampler's logo and some info about other pedals.

The pedal seems built as a tank with the appeal of a racing car.



Sets the overall output level of the pedal. It's is better to leave it a bit over the unitary level, while dialing the wanted distortion tone and then, to set up to Unitary Volume Level.


Sets the distortion level and character but is highly influenced by all the rest of controls and, specially the boost and bright switches.

Even / Bright toggle switch

Even mode has pronounced middles and balanced basses and trebles, it's more oriented to solid Rock tones. The Bright switch re-equalizes everything bumping the high end of the pedal. For some positions of the Tone control, it can be extremely harsh and, it's like using a razor blade to cut your ears.
The Bright toggle switch can help to some dark settings of the Middle Behaviour control and, has some resemblance to the edgy highs of some old fuzzes.

Standard / Boost toggle switch

On the Standard mode, the pedal sounds more crunchy and chunky and, it's more like a high gain overdrive than a distortion pedal. Since I've got overdrives enough and, I wanted a distortion unit, I feel at home with the boost always on, where you can get liquid and solid distortion.

Mid Behavior

This control sets the focus on the middle frequencies that you need for every case.  To the left, it focus over darker low-middle frequencies and, to the right it focus over harsh high-middle frequencies.
Settings affect to everything else, including volume, tone and gain.


This one helps to set the right amount of trebles, even if the Bright toggle switch is pushing hard.

Playing it

The standard mode is a bit out-of-my-scope, since I was interested more on the high gain side of this pedal. Even that it has usable sounds, I prefer the sounds I am getting from the rest of Wampler's overdrives for that work.

Toggle the switch to boost mode and, this is day and night. Something similar to the crunch/drive settings of the SLOstortion, even that the SLOstortion crunch mode seems to me more useful, instead.

Once the boost is on, you have THE distortion pedal. You can set up practically every wanted distortion sound. Maybe, it cannot cover extreme metal settings. Maybe, for this, you will prefer the Triple Wreck.
But, if you are after a liquid, singing distortion, with all the reminiscences of a big amp cranked to its best, organic, well structured and defined, this is your distortion pedal.

I was testing extreme settings in both directions: extremely harsh or extremely dull and dark. The tonal range of this unit is outstanding. I cannot imagine any user don't getting his/her dreamed distortion sound from this unit (except for extreme metal tasks, where I am not so confident).

I ran my tests with a PRS 513 Rosewood and, since this axe has the possibility to work in single-coil, humbucker and high-output humbucker modes, it's quite easy to see if the pedal is just a one trick pony for just a type of pickups and, it's not!. It works awesome with any type of pickup.

Particularly, I like the pedal more when the gain is between 11:00 and 14:00h. There you can get a gain structure very similar to a great amp well cooked, with lots of interesting harmonics.

First day I tried it with a Fender Stratocaster and, comparing the results with the PRS, I can say that the pedal preserves the foundational tone of your axe and, just adds what is needed to achieve that distortion tone that you were after.

Perfectly stacks with the rest of pedals and, without radically changing the distortion character of the Sovereign, any of the Overdrives of Wampler add their own touch. But, honestly, this pedal doesn't needs to be pushed, because it has gain enough.

Enough writing!. I think it's better that your hear the video I did during this session.


Not too much speech on this video, just the first 1:45". The video is lenghty, about 38 minutes of test.
I am demoing first the guitar "clean" tone and then, going to check random settings on the pedal.
I am starting on low gain settings, just to check what it does.
Then, I am pushing the gain with the boost toggle switch and checking the difference.
After this, I am checking more settings with medium and high gain settings, moving all the controls to several positions and, searching extreme settings, just to evaluate the versatility of its distortion tones.
Then, I am showing my proffered setting and testing it with the Neck pickup, that sounds absolutely awesome, as a flute and, comparing it with the Bridge pickup sound, brighter but with attitude.
After this, I am leaving my preferred setting there and checking how this pedal stacks with Wampler's overdrives: Paisley, Plexi Drive and Euphoria.
Then, I am comparing the sound of the Sovereign against the Pinnacle and the SLOstortion.
Finally, I am doing a test changing from single pickups to humbuckers and to high-output humbuckers to see if the pedal has some preference for a particular pickup type.
Get your pop corns, something to drink, wear your headphones and crank the volume. Enjoy!.
Forget my unstructured and sloppy playing, just hear the voice of the Sovereign!.

06 August 2012

Wiring DIY - Part 08

Modular approach to your wiring design

The best way to start designing your wiring project is to take a modular approach. Please, consider the following:

  1. Resolve everything related to a single pickup (coils out-of-phase, pickup out-of-phase, coil split, coils in parallel, etc) first.
  2. Resolve everything related to two pickups later.
From every "module" our goal is to get maximum two wires, the positive (the signal, the one that will be routed to the hot path) and the negative (the one that will be grounded as soon as possible).

If there is no need for using the negative wire in a further module, we will ground that negative wire whitin the module and, then, just the positive wire will exit that module.

Look at this random design approach:

The four conductors of the Neck pickup go to a Series/Parallel module, where we choose between to put both coils in series (standard humbucking) or in parallel. At the exit of this module we need to extend the negative wire, because we will allow to change the phase to whichever coils arrangement we choose on previous module. The negative wire can be then grounded on the OOP module, since there will be not needed anymore. The signal (coils in series in phase, or coils in series out of phase, or coils in parallel in phase, or coils in parallel out-of-phase) is then routed to the Neck controls (Volume and Tone, by example) and, from there, to the pickup selector (a blade switch, a swiftcraft switch or whatever else).

The four conductors of the Bridge pickup are reduced just to a signal output on the Module Humbucker/Split. This module will choose coils in series and in-phase or split to slug coil. Since the negative wire isn't needed anymore, because there are no other modules that need it, it would be grounded whitin this module. The output of this module (the positive, the signal) will be routed to the Bridge Controls (Volume, Tone...) and, from there, to the pickup selector.


For convenience, during the rest of wiring articles, we will use the following color schema for wires:

For Humbuckers: Seymour Duncan's color schema:

  1. Green: negative of humbucker and start of the screw (or outsider) coil.
  2. Red: positive or hot and finish of the screw (or outsider) coil.
  3. White (represented in light blue in diagrams): negative and finish of the slug (or inner) coil.
  4. Black: positive of the humbucker and positive and start of the slug (or inner) coil.
  5. Light Grey: the bare wire or any other plate ground wire.
For Single-coils:

  1. White: positive of the coil
  2. Black: negative of the coil
  3. Light Grey: plate ground (if there is)
  4. Red: positive tap of the coil (if tapered)
For the rest of the wiring:

  1. White (represented in light blue): positive wire, hot path.
  2. Black: negative wire, ground network.
  3. Inverted triangle: ground spot to the ground network.
  • Even if I am missing the plate ground wire of any pickup on the schema, plate ground wires go ALWAYS to ground.
  • Even if I am not representing the following wires: guitar's bridge ground, guitar's shield ground, those wires go ALWAYS to ground. Any other ground wire not represented goes ALWAYS to ground.


As we saw, we can get a maximum of 288 unique combos with two humbucker but, for this, some special switches must be used. When describing the several modules, we will consider that the complexer switch that we can have for each one is just a DPDT on/on switch.  This is convenient because, most of people doesn't like to modify the external appearance of his/her axe and, the use of DPDT on/on switches under a common pull/push or push/push pot.
When other switch is being selected for a certain mod, I will warn about it.

Single Coil Modules

We will discuss here the modules that can affect to just one single coil pickup, even that some of them can be used in general, as well.

Volume Control

Look at this picture:

The first schema corresponds to the typical way to wire a pickup to its volume control but, in a dependent way. If you have more than one single pickup wired in the same way, whichever volume control affects the whole output of the signal (that means dependent volume controls), because every volume control is "shutting up" the jack's hot.

The second schema corresponds to the independent volume control way of wiring a pickup to its volume control. The idea here is to "shut up" the pickup, instead of the jack. In that way, what happens to just on single pickup is not affecting to the overall output. This is the recommended way when more than one pickup (having its own dedicated volume control) can be selected at same time with others.

All the grounds should be linked together to create a grounding network and, it's very important that there is no ground-loop, since ground-loops are a source of noise. The best way to link all those grounding spots is in a single spot, that can be the backside of a pot's case, some screw on the shielded guitar cavity or, some improvised metallic ring where all the ground wires will finally land. It's up to you but, this is basic!.
Other side note about all this. If your electronic devices (switches, pots, etc) are all mounted over a foil or a conductive surface part of the shield, you don't need to throw any grounding wire to connect two different devices (that is, a wire from the back side of the switch to the back side of pot A, and from pot A to pot B, etc). If they all are laying over a conductive surface, their cases are already in contact so, you just need to solder your grounding wire to the backside of its case, to put every ground into contact.
Even that they aren't being represented in the picture above, your bridge-ground wire and your shield-ground wire (if your guitar is shielded) should go to the same central grounding spot as the rest of ground wires.
All these remarks related to ground are common to every module that we can see later so, I will not repeat this anymore!.

Finally, this picture are representing two ways of wiring a pickup to a volume pot for a right-handed guitarist!. If you are a left-handed guitarist, be sure to swap the two external lugs of the volume pot in this diagram!.

This diagrams apply to humbuckers and any other kind of pickup also, once you selected which coils will be in the hot path, they can be considered as single-coil pickups.

Volume and Tone Controls

There are three electrically equivalent ways to solder a cap to a pot to create a tone control. Look at this picture:

This creates some confusion but, in fact, the three ways are electrically equivalent.
We often see the second one on Gibson's LPs, by example, while the first and the third are more common on Fender's guitars. I can use any of those ways in my schemes at my convenience.

The important thing is to understand that a certain range of the high frequencies present on the signal wire (the light blue line) will be captured by the cap (orange) and then, throw to ground as soon as the tone pot is being rolled on.

Note that the negative lug of the cap is soldered to the case of the pot and, that case is being grounded (and, therefore, the cap). In guitar wiring, we don't use electrolytic caps so, any lug can be used for ground or hot but, many people prefers to ground the lug that is connected to the external plate or foil of the cap. We are always trying to leave the signal enclosed in a Faraday's cage!.

Once again, this schemes correspond to a right-handed guitar. If you are left-handed, please, swap the two extreme lugs in these diagrams.

Let use any of those three ways of wiring a cap to a pot and, let see the different ways to connect the tone pot to the volume pot. Take a look to this picture:

There are 4 ways to arrange volume and tone controls and, each one serves for a certain purpose.
As we seen, if the output signal is wired to the wiper (central lug), we have dependent volume mod and, if the output signal is wired to an extreme lug, we have independent volume mod.
If the tone input is wired to the volume's input, we have modern tone mod.
If the tone input is wired to the volume's output, we have '50s tone mod.

So, the first picture above corresponds to a dependent volume with a modern tone mod wiring. This is the most common way of wiring guitars that have global volume and tone controls. The drawback is that the sound goes very dark as soon as the volume control starts to being rolled off. That's the reason why a lot of people is trying to preserve part of its high-end content when rolling off the volume, with the help of a treble-bleed mod. This is the way as modern LPs were wiring, as well.

Second picture corresponds to a dependent volume with a '50s tone mod wiring. Tones were wired in this way on the earlier guitars but, changed to modern tone wiring later. This way of wiring the tone is smoother darkening the signal when the volume is being rolled off and, ads a bit of high-end to the signal when the volume and tone are both full on. The '50s tone mod is a good thing to test first before going for a treble-bleed mod. Is quite easy, requires no additional electronics (no more caps and resistors) and, it can be just what the doctor recommended to you. Try it!.

Third picture corresponds to an independent volume with modern tone mod wiring. This can be a way to make independent your volume controls in a LP-like guitar. By default, when you roll off one of the volumes, you are affecting the whole signal and, when one of the volumes go completely off, the guitar shuts up. With independent volumes, you can remove one of the pickups and the other will still sound, without issues. Since we have a modern tone wiring, no additional bright will be added so, if you liked the guitar sounded a tad darker, everything is OK.

Forth picture corresponds to an independent volume with '50s tone mod wiring. This is how the earlier Gibson's LPs where really wired. This gives total Independence to each pickup volume and, gives a bit of bright to the sound that helps pickups to shine a bit more over the dark wood tone. The '50s mod helps to maintain in a naturaller way the high end when the volume is being rolled off.

Once again: these diagrams correspond to right-handed guitars. If you are a left-handed, please, swap the two external lugs in EVERY pot (volume and tone)!.

Treble Bleed Mods

If you are looking for a Treble Bleed mod, first be sure to test the '50s tone mod, because it's a very natural way to loose trebles when the volume goes down but, if didn't worked for you then, it's time to test a Treble Bleed Mod. Look at this picture:

The upper one is the simplest treble mod that you can do in a guitar. It was often used in old Telecasters, to retain the snappy tone when rolling off the volume pot. To determine the right value for that cap has not direct rule, since it depends on the characteristic of your guitar's cable, the exact resistance of your volume pot and your pickup. Usually, values to work are between 620 pF and 2000 pF. Your ears will say which is the better value for your case. The drawback is that the guitar can sound unnaturally bright when turning down the volume.

Below, at left, we have the Kinman's Treble Bleed. This one uses a resistor in series with the cap, to reduce the amount of treble to be bleed out. The value of that resistor (and cap) must be determined also by every one but, usually, resistor values between the 50% to 100% of the pot resistance do the trick.

Below, at right, we have the Duncan's Treble Bleed. In this case, the resistor is in parallel with the cap, instead that in series, like in the Kinman's one. This changes the taper of the volume pot to better match the amount of treble bleed.

For single-coil pickups, the common values are a 1200 pF cap in series with a 130 KOhm resistor (for the Kinman's) and a 2000 pF cap in parallel with a 100 KOhm resistor (for the Duncan's).
For humbuckers, usually just a cap of 1000 pF does the job. I prefer Kinman's, because I don't like to change the taper of volume pot. Or 820 pF for the Bridge pickup and 1000 pF for the Neck pickup.

Note that any of those mods are linking the signal input and output lugs so, it works the same if we are wiring the pot as independent or dependent volume way. Note also that those mods are made on each volume pot that needs it but, it doesn't substitutes a Tone pot so, it's just an addition to what we were discussing previously.

Just search for treble bleed mod discussions and read the comments for every setup, to see which one can better suit your needs.

Full / Tap pickup selection

For those pickups with a taper, we can use a switch to select the full length of the wound wire or just up to the tapered spot.

Look at this picture:

The first schema is the most common way to select between the hotter and the weaker sounds of a tapered pickup. This is the way when the taper is closer (in number of wound turns) to the full finish wire.

The second one is the way if the taper is closer in wound turns to the start of the pickup.

For the third, we need an special switch, a DPDT on/on/on and therefore, it can change the aspect of your guitar. This kind of wiring makes sense only in the case that we can have turns enough of wiring between the negative wire and the tap and, between the tap and the positive wire as if they were two virtual pickups. By example, imagine that we wound from start to taper for a vintage-like single coil and, from taper to finish we wound for a Texas-hot single coil. If we choose from start to taper, we have a vintage pickup; if we choose from taper to finish we have a Texas-hot pickup; and if we choose from start to finish, we have a high-output modern pickup. Crazy, isn't it?.

Phaser switch

This can be used to change the phase of a pickup (single coil or humbucker), or to change the phase of a single coil (split humbucker, by example). If it is done inside a humbucker, it puts its coils out of phase.
If it is done at pickup level, it will put both pickups out of phase when both are being selected together.

What this DPDT on/on switch does is to reverse positive and negative wires. In-phase would mean that the input positive is being linked to the output positive and, the input negative to the output negative.
When the output negative isn't needed for a further module, you must directly ground it.
If you have one more module after (by example a serializer) you will need or not that negative output (depending on which pickup is being grounded by default in the serializer).

The phaser switch has no effect applied to just a pickup or coil. The effect takes place when the pickup is being combined with other pickup or the coil with other coil.

See that, in the picture, I am drawing a single-coil pickup with a bare (plate ground) wire. It's important that you do OOP operations with pickups that have the negative (start wire) from the plate ground wire, otherwise, you are positivizing something that was designed to control the noise.
This mod can, for sure, work even in two conductors single-coil pickups but, be aware that the risk of catching more noise is there!.

In other hand, not so much people loves the OOP sound, since the sound becomes nasal, hollow, thin and harsh. Anyway, I love more the OOP sound under high distortion, when you need a razor-like distortion that cuts everything with edgy trebles. It usually works better to put OP the Neck pickup, instead of the Bridge pickup, it's a bit smoother.

Be aware that, even that we named to this operation "to put out-of-phase or in-phase" a coil or pickup, we aren't affecting the phase of the signal in any single sense. We are just changing the electrical polarity of such a coil or pickup!.

Ok. On next part, we are going to describe modules that involve two coils or pickups.

05 August 2012

Pedals: Wampler Sovereign - First contact

My friend flyed back from NY and, bring me that highly wanted pedal as a gift to me (God bless you, friend!).
Even that it wasn't the best moment to carefully check the pedal, I couldn't wait more. I had to test it and, I did it!.

Well, I was waiting a great distortion pedal, based on the videos I've already seen but, I wasn't expecting the best distortion pedal I've ever heard.
Does it resembles any particular gain voice?. Mmm... I don't think so.
Can you get any type of gain?. Still not sure, I bet it but, I really don't care.

The word is ORGANIC. There is nothing that can sound remotely synthetic on this pedal. No fuzz-like distortion, no SD1-like distortion. It is like to step over a pedal to switch to the gain channel of an awesome amp. What I hear is just the harmonics exploding in my valves.
Note definition is at the same level as the Pinnacle (even better) but, the gain structure is way different. There is not that harsh high-end that you can find on Pinnacle (but, I bet you can even tweak this).

I spent no time checking every controls position. I just incorporated the pedal to my pedal board (oin the place that I was already reserving for this exact pedal) and tweaked a bit the controls to obtain a liquid, lush and sustained distortion with pristine note definition and, I've enjoyed the short session.
I have to check everything in depth (and I will release a dedicated article after it) but, at least, it was damn easy to get an awesome distortion voice in a minute. Practically, plug & play and, the sound was there!.

What interested me more about this pedal was just the generic approach of this Wampler's creation. Not emulating any particular amp this time but, just getting the best of any good tube amp.
What I wanted is just a good and versatile distortion pedal to sculpt my own signature distortion sound and, OMG, this is certainly the tool!.
Up to now, the most organic distortion in a pedal that I've heard was the ProCo RAT (when gain was just a bit over 12:00h) but, this Sovereign enhances this late in a geometrical progression.
Imagine that you have a good full stack amp, well cranked, with its valves boiling and exploding in harmonics and, you will be in the same ball park of the sound that the Sovereign delivers.

Once again, thanks a lot Brian. God bless your ears and your ability to transform what you hear in an pedal effect. I don't know how do you do it but, please, don't stop doing it.
But, over everything else, thanks a lot, from heart, Pep, you made me the gift I've been waiting for a long, long time!. You made me really happy, more than what I could explain.

Stay tuned. I will come back with an in deep test of this pedal during this next week.

Wiring DIY - Part 07

Humbuckers' sounds

A humbucker has two coils, therefore, we can have the sound of each coil separately, or the sound of both coils together arranged in several ways. That gives us the following 6 possibilities:

  1. Coil A
  2. Coil B
  3. Coil A in series and in-phase with Coil B
  4. Coil A in series and out-of-phase with Coil B 
  5. Coil A in parallel and in-phase with Coil B
  6. Coil A in parallel and out-of-phase with Coil B.
Those combos can be sorted from stronger to weaker in the following sequence: 3, 5, 1, 2, 4, 6.
Independently that this particular pickup can be put out-of-phase respect any other pickup (single or humbucker), its own coils can be put out-of-phase respect the other.

The standard way of wiring a humbucker is with their two coils in series and in-phase. This is the typical humbucker sound, powerful, warm, a tad dark, with good sustain and less bite and definition than single coils. Original humbucker had the wires of both coils soldered together and, what we had was just the starting wire soldered together to the plate wire and those, soldered to the metallic cover of a braided cable. The finish wire was soldered to the inner conductor of that braided cable.
In some cases we had this humbucker coming with a separate wire for the plate ground, but this is really rare.
Those kind of humbuckers have a single sound, both coils in series and in-phase (pure humbucker sound). They doesn't allow any other combination. Even that we could put that pickup out-of-phase with other, this is a bad thing, since we are positivizing the cover of the pickup and the braid of the braided cable, removing the Faraday's cage that covered both, the pickup itself and the inner signal conductor, potentially making the guitar very prone to catch noises of any kind.
To be able to put a humbucker out-of-phase, without risks, we need the plate ground in a separate wire (usually a bare wire) and two not-braided conductors, that can be twisted together.

If you are thinking on doing some mod to your humbucker loaded guitars, be sure to get a humbucker with 4 conductors + plate ground wire, instead of the classic single braided conductor ones. In that way, you will be always able to select any of the 6 combinations we already mentioned above and, even to safely put out-of-phase this humbucker respect any other pickup in your axe.

Look at this picture:

We are using here Seymour Duncan's color code. The coil with adjustable poles is often named screw-coil and, the coil without adjustable poles is often named slug-coil.
The start wire of the slug coil is the black wire and, its finish is the white one (represented here in light blue).
The start of the screw coil is the green wire and, its finish is the red one.

The first picture is the standard humbucker mode, that is, both coils in series and in-phase.
The second picture is coils in series but out-of-phase (OOP from now). Note that the wires of the slug coil were inverted on connections.
The third picture is coils in parallel and in-phase (from now, if we omit it, it means in-phase).
The forth picture is coils in parallel and OOP.
The five picture is really two pictures. The first one corresponds to the selection of the slug coil, where the white wire goes to hot and the black to ground. The second one corresponds to the selection of the screw coil, where the green goes to ground and the red to hot.

When one of the coils is selected, instead of both coils, it's being named coil-split. So we can coil-split to slug or to screw coils. For sure, every humbucker is not made the same and, while the most have one slug coil and one screw coil, there are other designs were both coils have adjustable poles, or even blades or, the cover doesn't shows the poles below.
We will use this convention to name the two coils of a humbucker, just for our convenience and, will represent any humbucker in that way, independently of the real aspect because, at the end, the only important thing is to understand how to get the 6 different sounds and which one to choose for each application.

When we need to put this pickup OOP with another one, we will just need to swap the black and green wires in those pictures above.

The most wanted mod, respect of humbuckers is just the ability to choose humbucker or split mode with the help of a switch. Look at this picture:

The first corresponds to a way to select humbucker/split to slug. It needs just a SPDT on/on but, you can use any bigger switch but, just use one pole.

The second corresponds to a way to select humbucker/split to screw. It also needs just a SPDT on/on but, this is a bad way to do it. The issue here is that white and red are put together with black in the hot path. This shortcuts slug coil but, there is something the risk of some bleeding from that coil.

The third picture corresponds to a way to select split to slug/humbucker/split to screw. It needs a SPDT on/off/on (center off) switch but, it presents same potential issue than the previous one.

A better way to do this two last mods is to use a DPDT and a 3PDT switch instead, to completely remove the slug pickup from the hot path. See the following picture:

The first case corresponds to humbucker/split-screw, with the help of a DPDT on/on switch and, removing any possible bleeding from the slug pickup (as happened before).
The second case corresponds to screw/humbucker/slug, with the help of a 3PDT on/on/on switch (type 2).
If you don't understand how it works, just print out this picture 3 times and, put in each printing, the status of the switches so you can get the picture what is being connected for each case.
The exit of both pictures is the orange wire (HOT) and, the ground is being represented by this inverted triangle.

The two first schemes of the first picture and the first schema of the second picture can be implemented by using a pull/push or push/push pot and, therefore, the mods will not alter the external aspect of the guitar.
The last schema of each picture need some toggle or rotary switch, instead.
That's why, we will usually see a humbucker/split switch that will split to just one of the coils; which one will depend on how are we wiring the switch but, the usual is to split to slug coil.

To be able to select the 6 different sounds of a humbucker, we will need a 4 poles 6 throws switch and, this is usually only possible with a double-wafer rotary switch.

In the above picture, the positions correspond to the following:
  1. Humbucker (in series)
  2. Coils in Parallel
  3. Split to Slug
  4. Split to Screw
  5. Series OOP
  6. Parallel OOP
Rotary switches can be placed instead of a pot, they usually fit to same space.

If your guitar has 2 humbuckers and you put a 4P6T rotary switch for each humbucker (to select its own 6 sounds) and you place one more 4P6T switch to combine both pickups, you have all the possible sounds that 2 humbuckers can generate. That means 6 * 6 * 4   = 144 different combos for the central position, when both humbuckers are selected together, that, combined with the 6 sounds of each pickup alone, makes a total of 156 unique combos with 2 humbuckers.

It can sound very exciting but, to be honest to test more than 20 combos it's really difficult, first because of the time it requires and, second because when you are trying the 21 you already forgot the previous 20.
This is a good exercise to make to a lab guitar, to help you to exactly determine which combos make any sense for your needs and then, design the right wiring diagram that includes those must-have combos.

You will see with the time that not everything is useful for you. Many people doesn't like OOP, since it makes the sound weaker, thinner, nasal, hollow and tiny but, Peter Green's middle position has the Neck OOP respect of Bridge and, it sounds damn good.
You will discover that there is not so much difference between the slug or the screw coil and, this is specially true if the humbucker has twin coils. In some cases, the difference is so notable that you will prefer to just get one of the two and not the other.

Don't be worry if you don't fully understand the schemes above. You can come back to this page one you are more schooled in wiring diagrams.
On next part, we are going to discuss the modular approach to design your own diagrams.

03 August 2012

Wiring DIY - Part 06

Pickup' sounds

Well, pickups have a default sound but, this sound can change in determinate circumstances. We are going to see the different ways that common pickups are working and which alternate sounds can give.

Single Coil Pickups

We saw that a wire is wrapped around a magnet (or magnets) in a long run of about 7500 turns. One of the extremes of this wire is the Start wire and, the other extreme is the Finish wire.
Usually, the start is considered negative and it's being grounded, while the finish is considered positive and it's linked to the signal output. This will deliver the sound as it was designed, with the right magnetic and electrical phase.

Every coil has an start and finish wire and, every pickup has a plate ground wire.
So, we can have three wires in a single coil pickup: the start, the finish and the plate ground. On single coils, usually the plate ground is being soldered together to the start wire.
If the pickup has a metallic cover, that metallic cover is soldered to the plate ground. That helps to create a Faraday's cage around the pickup, with a good rejection of EMI and RF interferences.
The drawback is that, if you do an out-of-phase mod, and you aren't separating the plate ground wire from the start wire, you are positivizing the cover and creating some kind of antenna that it's potentially noisy.

So, if you ever had to work with an out-of-phase mod for a single coil with cover (as some P90, by example), you should separate the plate ground wire (that would be grounded, always) from the start (negative) wire (that can go to hot or ground, on demand).

See this picture, where it is shown the two ways to wire a single coil pickup.

The upper case corresponds to the regular way to wire a single coil pickup. This is being (wrongly) called in-phase.
The lower case corresponds to the alternate way to wire a single coil pickup and it's being (wrongly) called out-of-phase.
What in and out of phase really mean is that you reversed the electrical polarity of the signal but, signal phase has nothing to see with all that. But, because this is the wide spread name, we will use it to describe this kind of arrangement in our wiring.

Remember that, the plate ground and start wires can be soldered together (this is the usual stock way of delivering single coil pickups). You will notice that some Telecaster's pickups have 3 conductors, instead of the typical 2. This is because they are separating the plate ground from the start wire, to allow you to perform some mods that include an out-of-phased pickup (as seen in the Fender Tele Baja Player, by example).

Any pickup out-of-phase alone, has no noticeable change on its sound (well, some people can hear very discrete and negligible differences). When it makes the real difference is when it's being selected together (in series or parallel) with other pickup then, the sound becomes hollow, thin, nasal and twangy. The depth of the effect depends on the two pickups being combining and, how their respective frequencies are being cancelled or reinforced.

Tapered single coil pickups

A tapered coil has two finish wires. The first one corresponds to the number of turns that provide a vintage-like tone while, the second one adds some additional turns to make the coil hotter. This is a very wise way to use same coil to deliver two very different flavours, one vintage and, one more modern, with more attitude. Imagine that you connect a wire to the turn number 7500 but that, you continue wounding the coil up to 15000 turns, where you have the real end of your coil's wire.
To choose one or the other finish wire can be done with the help of a SPDT on/on switch.

Look at this diagram:

There are two ways as you can considered the tap wire. If the tap wire is closer in turns to the finish wire, you can use the diagram above, this will consider all the turns between the coil start and the tap wire and, the whole coil for the finish wire.
In the case that the tap is closer in turns to the start, you can ground the tap to achieve less turns, instead.
In any case, if you route to hot the tap wire, you will consider the number of turns between the start wire and the tap wire. If you ground the tap, you will consider the number of turns between the tap wire and the finish wire.
Therefore you can have up to three different sounds in a tapped coil: start-to-tap, tap-to-finish and start-to-finish. Three different number of turns, lead to three different sounds.
Sometimes, the number of turns between the tap wire and the finish wire are so small that we cannot achieve an useful sound for tap-to-finish combination but, if the pickup is hot enough, we can do this:

On this diagram, the different status of the DPDT switch are shown with that purple lines connecting the lugs of each pole for each of the three positions of this DPDT on/on/on type 2 switch.
The Upper case, will give us a tap-to-finish coil' sound.
The Middle case, will give us a start-to-finish coil' sound.
The Lower case, will give us a start-to-tap coil' sound.

So, imagine that we have the coil wound as vintage from start-to-tap and, vintage-hot from tap-to-finish. We can achieve very three different sounds: up = vintage-hot, middle = modern-hot, down = vintage.
But, this is only possible depending on how the pickup was tapped.

We will continue describing the 6 different sounds of a humbucker, in next Part 07.

Wiring DIY - Part 05

Slide Switches

Slide switch types are very limited. An inner plate slides over two rails establishing contact with a couple of lugs (per pole). The most common types are SPDT and DPDT. They work exactly the same as we were describing on Part 03. DPDTs can be with center on or center off. In the case of center off, there is no contact in the middle position. In the case of center off, we have a DPDT on/on/on Type 1 (as shown in Part 03).

Gibson' Swiftcraft type switch

This is a tricky DPDT on/on/on switch.
The two poles are the two central lugs. When the handle is on the middle, the 4 lugs are in contact but, in pairs.
When the handle is at right, the 2 lefty lugs are in contact and, when the handle is at left, the 2 righty lugs are in contact.

This picture shows the three positions, looking at the bottom of the switch.

The upper lug on this picture is the grounding spot for this switch.
So, usually the two central positions (poles) are soldered together (to the output) and, each extreme is usually linked to one pickup (or the volume pot that controls that pickup).

Fender' S-1 switch

This is a push/push pot that comes with a wafer with 4 poles and 2 throws by pole, that is, a 4PDT on/on switch. Every time that you push the button, the switch changes the throw.
Everything that you do with an S-1 switch, can be done with a mini-toggle 4PDT on/on switch but, a toggle 4PDT will require additional space in your electronics cavity and, will need to route some other hole in your pickguard or guitar body. The nice thing of the S-1 is that is hidden under one of the pots and, it's small enough to be fit guitar's cavity.
This switch is usually seen in Deluxe or very special models, where a lot of alternative combinations are being offered stock.

This is what happens on this switch (seen from the bottom):

The lugs or contacts of this switch aren't arranged on columns or rows but, they work under same principles of any 4PDT on/on switch.

Rotary Switches

Rotary switches  have a lot of variety, they are multi-pole and multi-throw. Usually, way more throws than poles in the same switch. The most usual rotary switches that you will find in a guitar will have 2 or 4 poles.
Usually, for each pair of poles, those poles and their corresponding throws are distributed in a circular wafer. So, a double pole rotary switch will have a wafer and, a four poles rotary switch will have two wafers.
Usually, it makes no sense to use a rotary switch with less than 6 throws, since we already have blade switches that cover up to 4 poles and 5 throws (as the super switch) but, sometimes, there is not room enough in our cavity to mount a blade switch. In those cases, one pot can be sacrificed and a rotary switch can be installed in its place, instead.

Some PRS models are using a rotary switch to select their pickups' combinations. Some Gibson's include the Varitone mod, that works with the help of a rotary switch. There are some other uses, for sure.

Look at this picture, showing some samples of Rotary Switches, seen from the bottom:

The upper left one is a DP4T rotary switch, the poles are those red and dark blue dots. Usually, poles are placed on the center, if the switch has just a wafer.
The upper right one is a DP6T switch.
The lower left one is a 4P3T switch, a rare case where there are more poles than throws.
The lower right one is a 4P6T, with two wafers. The occult wafer corresponds to the lugs that are shown peripherally. Note that the poles of the lower wafer aren't on the center (lugs labeled as C).

Rotary switches are the kind of switches that have more diversity so, if you are looking for a certain combination of poles and throws, it would exist a rotary switch that has it.
The drawback is that every rotary switch is being implemented in a different way. Where are poles placed and, to determine which position corresponds to each throw isn't always easy so, be sure to read their specifications to have a clear picture on how they work. What is common is that for each turn (throw or position) every common (pole) that the switch has, will be connected to the lug that corresponds to such a position. If the switch have 6 poles, and we are switching to position 1, every one of the six poles will enter in contact with its lug corresponding to position 1.

At this point, we reviewed the main electronics components that we can find in a guitar so, we can start describing the different ways to connect pickups and which sound we can obtain for each way. This will be described in next Part.

02 August 2012

Wiring DIY - Part 04

Blade switches

Blade are the quickest switches for a pickup selector. From the very beginning, Fender's guitars come with some blade switch to selecting the different combinations of their guitars.

There are 3-way switches, with just 3 real throws and positions, that just individually select one of the pickups (neck, middle or bridge), there are 3-ways with a pair of notch-positions that allow 5 positions, there are 4-way switches used in Telecasters and, there is the Super-Switch, with 5 real throws and 4 poles.

Usually, those switches have 2 poles and from 3 to 5 throws so, we are talking about DP3T, DP4T and DP5T switches, except in the case of the super switch that, since it has 4 poles, it is actually a 4P5T.

Each pole of this switches have a lug for the pole (named common) and a lug for each throw.
Let see some examples:

The one named Fender is the typical DP3T (5 handles) switch found in Stratocaster guitars. The common lug is labeled C in this picture. Lug B corresponds to Bridge pickup, lug M to Middle pickup and, lug N to Neck pickup. Each side is independent of the other one.
As you can see the Stewmac is similar but, arranges lugs in different order and, Mega-Switch (Schaller) and Asian importation switch arrange the two sides in the same row but, they also differ on the position of the lugs corresponding to the two poles (or commons).
The lug labeled with a G corresponds to GROUND, the grounding lug for this switch.

Look at this picture:, that corresponds to a Fender's old 3-way blade switch, a DP3T with just 3 positions..

On light blue are being shown which lugs of the first pole are being connected, when the blade is on the 3 different positions, being Pos 1 the typical position to select the neck pickup and, the highest position number is the typical position to select the bridge pickup. But, for sure, you can do anything else!.
Each side of the switch, that corresponds to the different alternative ways (B, M, N)  for a certain pole (C) is totally independent of the other side.

Now, look at this new 3-way switch, with 3 throws but 5 positions (2 notch-positions) that is being spread used in Stratocasters:

As you can see, positions 2 and 4 (the notch-positions) are tricky, since there are two throws connected to the common at same time. This is the typical DP3T-5 positions switch of Stratos.
The Stewmac, the Mega-Switch and the Asian importation switch, all work in analog way but, lugs are being arranged in a different order.

Be careful with Ibanez switches, some are following the same connection pattern shown above but, there are some models that work in a very different way and that are being designed to cover some special coil combinations in axes with a pair of humbuckers.
Also the 4PDT with 3 positions that they are using in some axes to select pickups, works with a center position very different of the 4 types that we described before.

The upper switch corresponds to the most common implementation of a 4PDT on/on/on switch (we named it Type 2) but, look carefully to the lower switch, the Ibanez version arranges the central position in a way that doesn't corresponds to any of the types we already described. So the learning is: be sure on how the central position of your switch is being implemented, in case of Toggles and, in case of the rest of switches, it is also important to understand how they work, before facing any project.

The Fender's 4-way is typically found in moded Telecasters with the bridge in series with neck additional position. This works like the old 3-way position but, with one more lug, throw and position. It is a DP4T switch.

And now, we have the Fender' Super-Switch, probably the most interesting type of switch for any kind of modification in a guitar. Since it has 4 poles, it allows to select 5 different ways for 4 different wires at a time and, that is a bunch of different possibilities.

As you can see, there are 24 lugs on this switch, separated into 4 groups (one by pole).
Lug 1 corresponds to position 1 that corresponds to when the blade is in the upper side (typically, neck), and position 5 corresponds to when the blade is in the lower side (typically, bridge).
Each group (common and lugs 1-5) is completely independent on the rest of groups.

There are also Mega-Switches and Asiatic switches that work similarly but, they have two groups in each face of the switch.

We will describe some more typical switches in next part, as the Gibson's, the Stewmac's Freeway, the Fender' S-1, slide switches and rotary switches.