Ask the Guitar Guy: About Intonation

Ask the Guitar Guy: About Intonation: Intonation....if you are a guitar player, you've probably heard that word many times. What exactly is intonation, and how does it affect...

About Intonation

Intonation....if you are a guitar player, you've probably heard that word many times. What exactly is intonation, and how does it affect the performance of the instruments.
Funny, I used to listen to the Beatles tracks on vinyl, and wondered why everything sounded like it was maybe not quite in tune, and then, in another passage of the song all was okay, and that resonate 'warbling' seemed to go away.
Well, what was wrong back then was their instruments, though they were some of the best for that time, were not properly intonated. In fact, Paul McCartney's bass guitar was almost impossible to intonate. It was a Hofner, and it was prior to Hofner's introduction of a truss rod. Being a short scaled instrument, as he played up scale (anything past the seventh fret) the guitar progressively became out of tune. I'll explain why in a bit, but suffice it to say there was not a lot the Beatles could do back then to make things better.
Since then, with the advent of digital remastering, they were able to take existing tracks and specifically correct the tuning of Paul's guitar, one note, and one song at a time. One of the big reasons digital remastering has caused some conflict with the original recordings.
Anyway, enough about that.
What is intonation? Basically it is re-defining the fretboard on any instrument to provide consistency in pitch as the guitar is played up scale.
A guitar neck is made up of a series of equations, and all have to coincide in order for it to work correctly. There is the scale of the neck, that is basically the distance from the inside of the nut, to the centre of each of the saddles on the bridge. Scale length can change depending on the instrument. For instance, a bass guitar can't be expected to have the same scale as a six string. And a dual octave, or twenty four fret guitar has a different scale length than a 22 fret instrument. Still, regardless of either, the centre of the guitar is alway the half way point. The Twelfth fret.
Other equations that fit into the mix here are the fretboard radius, the amount of relief on the neck, the thickness of the frets, and even down to the type and size of the string used on the instrument.
Basically, in a nutshell, intonation, depending on what other equations we have discussed, is the exact distance between the nut and the twelfth fret, and the twelfth fret and the bridge saddle.
Once a guitar is set up with the proper gauge of strings, and is tuned to whatever tuning it is normally tuned to (and believe me, there are many) the very last thing that is checked, set, or reset, is the intonation.
How is this done?
Most guitars, Fender, Gibson, PRS, G&L, Ernie Ball, and others, all feature a bridge made up of adjustable saddles. Intonation is set at the twelfth fret. The string is played 'open', and then checked at the twelfth. If the pitch of the note is higher at the twelfth than the open string, the saddle must be adjusted to compensate for all of the other variables we spoke of earlier. If the note rings higher than the open note, the saddle must be adjusted toward the tailpiece. If lower, towards the neck.
One would almost think the opposite, but keep in mind you are not tuning the guitar, you are selecting a bridge saddle position that best centres the string for both scales, on either side of the twelfth fret, which is the exact centre of the fretboard.
Years ago, saddles were not adjustable. One could fine-tune the bridge on the guitar, simple by moving it around. They floated on the guitar, and could be moved back or forth, and even tilted in order to get the guitar close to pitch.
Might have worked for the day, but that was really a poor approach to intonation.
A string's thickness also affects the intonation on the instrument, so intonation should always be checked when strings are changed to a heavier, or lighter gauge.
Changing the gauge of the strings also affects the relief on the neck. Relief also affects intonation.
Floyd Rose tremolos, are great for what they can do to change the sound of the instrument, but they are also a nightmare to set up, if you are not really familiar with them, and intonation on these can be a bit of a chore to set up.

What about acoustic guitars? Do they have to be intonated?
Of course they do. Acoustic intonation works much the same as their electric family members, the only thing different, is they usually feature 'fixed' intonation, by means of a compensated bridge / saddle. You might notice the bridge saddle slot on acoustics is milled out at a slight angle, never straight. This is the compensation for the intonation. Sometimes this is not enough to maintain the guitar's intonation and pitch, so the bridge saddle is further compensated on the bridge saddle. Have a close look if you own an acoustic, you might notice the saddle is stepped back, usually at the second string, to further compensate pitch.
A high end guitar might feature compensation on all of the individual strings.
It is important to remember which way the saddle goes into the slot when you remove and replace strings, because if it falls out and becomes reversed, your guitar is not going to sound right. Same applies for an electric archtop with a floating bridge. If the bridge comes loose as a result of string removal, you first want to maintain it's position as far as how it is facing the tailpiece, and exactly where it was situated on the guitar, to maintain intonation.
Always mark the position of the bridge on an archtop with a piece of black electrical tape. Simply align the tape with the position of the bridge prior to removing strings. Don't mark the guitar. After you reposition the bridge and install the strings, simply remove the tape. No mess, and no headaches.

Can you turn a right handed acoustic into a left handed acoustic guitar. Basically, no!
This simply will not work.
I have seen where the fella at the music store down the street, in order to make a sale, switched the nut on a right handed acoustic to a left handed nut. I would say he might have made up a new nut, but he wasn't that bright. He then went on to string the guitar upside down. This doesn't work.
Why?
Intonation! Plain and simple. The compensation on the saddle will be facing in the wrong direction, so as a person plays the guitar upscale, it continues to go out of tune.
Don't do this. It's not cool. If you need a lefty, buy a lefty. They make them everyday.
Regardless of the stringed instrument, intonation is a requirement.

Now, let's get back to Paul McCartney's bass.
Why was it sounding out of tune as he played the higher notes? He played a Hofner bass.
Back in the day Hofner never built a bass with a truss rod. Not even a steel re-enforced neck. So when Sir Paul used to tune his bass to A-440 hz, or piano pitch, the neck used to bow up on relief. This changed the respective position between the nut and the twelfth fret. The problem couldn't be rectified by adjusting the floating bridge on the Hofner 500/1, because the problem was between the nut and the twelfth fret, not the 12th fret and the bridge. So it would have been very difficult to eliminate in the day. Hofner has since corrected that problem, and installed a truss rod in their necks. Huge improvement.
Still, if Paul would have just used a Fender Precision back then, in all likelihood, that would never have happened. Thanks for digital mastering. The old recordings used to make me cringe.

So that is a bit about intonation. Maybe now you'll know what folks are talking about when they mention that word.
Till next time folks! Keep rockin'!!

Brett McNaueal

Tonewoods Part Two

Last week we talked a bit about tone woods, and what most guitar manufacturers use, and why they use that specific type of wood. This week I would like to talk about the 'other' wood used on the acoustic guitar, that being the soundboard.

The soundboard on an acoustic instrument is the top of the guitar, or the part of the instrument you would rest your hand on to play.

Though they can differ from manufacturer to manufacturer, the majority of the folks that build them use spruce as a soundboard.

The reason for spruce? That word 'resonance' returns again at this juncture in our story. It's how the wood vibrates and transfers sound to the sound box. Guitar builders have tried many other woods over the years, like poplar, maple, cypress, cedar, birch and many more as a sound board, but time and again 'spruce' seems to be their first choice.

Spruce can be somewhat fragile so it is usually the premium select grade that is used here. It can't have knots or wavy grain or other anomalies. That would simply change the tone.

A soundboard must be consistent in grain and is usually book-matched with a similar piece to make up the soundboard on an acoustic instrument. Book-matching means taking a piece, usually hewn from the same part of the tree, and glueing both pieces together, side by side. This makes the wood resonate better, and cosmetically is more attractive on the instrument. Some builders choose to laminate their soundboards using a combination of varying pieces, and glueing these together, but those guitars are usually low end, or guitars that are painted, so as the laminations aren't as visible.

There are many different types of spruce, but the choice of most builders usually comes down to three, Sitka, Englemann, and Adirondack, with the majority of this wood coming from Canada, the U.S. and Europe.

To get the proper 'timbre' (pardon the pun...that is not timber) or resonant tone, these soundboards have to be seasoned very gently, as drying of the wood too quickly will only go on to cause cracking and other issues down the road.

Some guitar builders, and I will use Martin again for an example, also take this a step further and reduce the thickness of their soundboards in certain areas to create more volume from the instrument and differing tones, depending on where one would strum the instrument.

Nonetheless, I could go into great detail on this subject, and still come up with the same common denominator, and that is soundboards can vary in dimension and type of wood used, but they all do basically the same thing, and that is amplify the instrument through the sound box and back out the sound hole, or 'F' holes if it is an archtop guitar.

Cedar can also be used as a soundboard in guitar building. Though it is used mostly to build classical instruments, it is also starting to be used more and more as a soundboard by some popular steel string builders as well.

Cedar is a little more 'dull' in sound in comparison to it's spruce cousins, but the right type and thickness of cedar can feature similar tones to spruce. Cedar is a very fragile, delicate wood, and must be conditioned with care before being used as a soundboard. Some cedar is found in Canada and the U.S., but the majority of the cedar used to build fine quality instruments comes from European countries, and also from Norway, Sweden and Finland.

Electric instruments are not as fragile as their acoustic relatives, and the choices of woods for their make up can be much the same as acoustics, and much different at the same time.

Some electric builders, like Gibson, PRS, Gretsch, and quite a few others, also tend to use mahogany for the production of the necks and headstocks on their instruments, and in some cases, the bodies as well. Some of these builders utilize a 'set' neck design, which shares a lot of the same characteristics as the dovetail on the acoustics. The neck is set, or glued onto the guitar in such a fashion that it marries the body in what looks like a mortise and tenon joint. Kind of like over-lapping one onto the other. The guitar is notched out to meet the neck extension, and that is glued together directly below where the

neck pickup is mounted to the instrument. The advantage of this is 'tone'. Massive tone!! And that is started at the headstock, where the strings attach, transmitted through the neck and fretboard and directly into the body of the instrument. Disadvantages?? Well, if you ever have to remove the neck, because it might have suffered a broken neck, or requires a neck reset, you are pretty well out of luck here.

You would have to bring it to a certified luthier to have the neck removed, repaired and replaced on the instrument. Sometimes, it's just as easy to buy a new guitar, for what the repair is going to cost.

Fender, on the other hand, doesn't do it this way. The bulk of the guitars and basses Fender makes, all feature a 'bolt on' neck, which really isn't bolted on at all. It is screwed on to the body. So, I am not too sure where that term ever came from. Some builders, like myself, prefer to bolt the neck onto the body. That is achieved by installing threaded inserts into the neck and instead of using wood screws, you would use machine screws, or bolts. This adheres the neck better to the body, thusly improving tone, and there is less chance of the neck moving if the headstock gets bumped, or the guitar suffers a fall.

Fender's choice in woods did vary, but only slightly. Fender is very traditional with what woods they use to build their guitars.

Fender necks are usually always made up of select rock maple, and their fretboards are usually, either rosewood, or maple.

Fender bodies can be made up of a multitude of different woods, but their stock instruments are usually made up of either 'Alder” (American clear poplar) or Swamp Ash, though Fender has also dabbled with other woods for their bodies, like Koa, White Ash, Walnut, Rosewood, Cherry, Curly or Flamed Maple and Mahogany.

I have built a few guitars of my own recently, where the bodies were built for me by a friend of mine in California at Matt's Woodworking. His name is Keith Brommerich. These guitars were solid one piece walnut. They turned out beautiful. Walnut has to have one of the prettiest grains I have ever seen, and these guitars come to life with just a little light finishing on the bodies. They also come to life when they are played, and sound unlike anything I have ever heard before. Thank you Keith.

Fender, unlike Gibson and others, uses single coil pick ups in their guitars. Some argue that regardless of what wood is used on the guitar, by using single coils, one doesn't change the tone, or sound of the guitar. Well, I really don't believe that to be true. I believe that anytime any pickup is somehow fastened to an instrument, the sound is changed by the type of wood that the pickup is attached to. Ash sounds different than alder, and Cherry sounds different than walnut.

Gibson, with their humbucking PAF design pickups? Well, that is a whole new ball game.

Gibson knew what they were doing from the get-go, by using the all mahogany body and the humbucking pickups. That was just the sound that everybody was looking for at the time. And the heavier the guitar, the better the tone. Though wearing a 13 pound guitar all night is not what I would call appealing at best, Gibson has sold some guitars, and continues to, even to this day. The Les Paul or the SG hasn't really changed in look a lot, but they have in sound. Why? Well some brilliant engineer at Gibson decided to take what was already great and put his spin on it, and came out with the natural series, the weight relieved and the chambered series guitars. Guitars that look the same, but don't sound the same. Mainly because they removed from the guitar what mattered most. The wood. It is seldom at best you can get a solid wood anything from Gibson. In trying to save the planet, it seems they forgot about what matters most...the tone!! And what makes the tone? A combination of things, with the wood being number one. Pure and simple.

Though Fender has changed some of their lineup of instruments, they haven't changed their basic guitar design and principle. That of course being what Leo Fender started years ago when he would hand select the neck and bodies himself for his guitars. Don't mess with what works. Gibson needs to take a good hard look at this, and go back to what they used to do. Again, don't mess with what works.

That is also why you see companies like PRS, Carvin,and MusicMan, building some great guitars. They are just simply doing what companies like Gibson used to do, and are doing it a whole lot better.

Their quality control is better and more consistent and they make their guitars out of what matters most....real wood.

That's all for this week. Have a good one. See you next time.

Cheers!

Brett McNaueal

About Tone Woods

Hope everyone had a great week.

This week I would like to talk about tone woods. What makes them different, and what you can expect in how these woods perform

You might think, like a lot of folks, that a guitar, acoustic or otherwise, is just simply made of wood, and when you put strings and electronics on it, it makes music. Well... it's something like that, but just a bit more involved.

There are a multitude of different tone woods that are used in the manufacturing of acoustics, solid bodies, arch-tops and basses.

Let's start with acoustic guitars.

The most widely used tone wood used in building acoustic instruments is mahogany. Why? Well, it's affordable. It is reliable, (doesn't twist and is a relatively tough wood) it is an attractive wood, and it is easily finished. It also lasts for years, and requires little to no maintenance. But, the biggest reason for using mahogany is that is resonates so well.

Martin Guitars tend to use a lot more of this wood, comparatively to other manufacturers such as Gibson, Larivee, Breedlove and others.

Martin uses Mahogany on the backs and sides of their guitars, as well as the neck and their head stocks.

Martin guitars have a distinctive sound unlike any other guitar. Though other Luthiers and guitar manufacturers have been trying for many years to find out how they achieve the sound they do, even with the right equations and engineering to duplicate the Martin 'sound', they have always come up short. They are truly a remarkable instrument.

Though Martin, like so many other builders, do not like to share their secrets, other builders, even in coming close to duplicating the Martin sound, have in their own right discovered their own unique sound.

The sound of the instrument is not 100% dependant on just the tone woods alone. With Martin, and so many others, it is the right combination of a lot of things.

Let's move on to other tone woods and why they are used, and where they are used on the guitar.

Sticking with acoustic guitars for this portion of this blog, Rosewood is probably the next best choice for guitar builders. Rosewood comes in many varieties. Macassar, Indian, African and the most popular, Brazilian. Rosewood is a very fragrant, oily, and porous wood. Still, when it is seasoned properly, rosewood can be as dense a ebony and duplicate a lot of similar characteristics in tone, but at half the price. Again, this is one of the reasons rosewood is a popular choice for use on acoustic, and some electric instruments.

Where is it used? Rosewood is usually used as fretboard material, headstock laminate and most importantly on the back and sides of the instrument. As a soundbox choice, (the back and sides of the acoustic guitar) rosewood is less aggressive and more resonant than mahogany, it's cousin, but if used on dreadnaughts and jumbo guitars, rosewood provides a very rich and distinctive tone. Rosewood has been used for years by many manufacturers as an alternative to mahogany and other tone woods. Rosewood is also used in the manufacture of the bridge plate on the guitar, as well as the sub plate, that is the plate affixed to the guitar's bracing and is attached to the underside of the soundboard, or 'top' of the instrument. Rosewood is also used as the inner purfling on a lot of higher end instruments. Why? Simply because it vibrates and resonates better.

The only problem with rosewood is that it is a somewhat 'oily' wood, which makes it difficult to adhere to the neck material, as well as the soundboard on acoustics. Great caution has to be taken to make sure the wood is properly conditioned and seasoned, or 'aged' as well as the use of correct adhesives for the process.

As guitars mature, one will often see where binding attached to rosewood has started to crack and craze and eventually pull away from the instrument. Gretsch and Gibson, to name a few, are re-knowned for these issues. Gibson also had problems with their rosewood bridge plates lifting on their guitars, and eventually moved on to a different wood for this purpose.

Ebony is next on the agenda.

Ebony is a very dark, black wood. It is very dense and somewhat fragile with age, if not conditioned properly.

Where is it used on the instrument? Usually ebony is used as fretboard material, but can also be used as a bridge plate, or a laminate with other woods for dressing a headstock.

Ebony has an advantage over rosewood in that it is extremely dense, less prone to wear and usually works well in adherence to other woods like mahogany.

A huge advantage in using ebony as a fretboard material, is that ebony does not wear out like some rosewoods do. So there is never the concern to having 'divots' in your fret beds.

These divots, or wearing out of the fret beds (in between the frets) has always been a great concern to manufacturers, because when this happens, there is usually little one can do to repair this, but replace the fretboard, or in some cases, even the entire neck on the instrument.

Now that is all the good stuff about ebony. Surely there has to be some disadvantages right?

Well, to answer this...yes there is.

The biggest problem with ebony and its choice for either a fretboard, or a bridge plate, or anything else on the guitar, is simply that it is a very fragile wood. Ebony never stops expanding and contracting as it takes on and expels moisture and humidity. This is caused by the raising and lowering of the humidity in the ambient air in the guitar's environment, and also from the very moisture in your hands and fingers. Due to the constant changing of this wood's conditioning, it is prone to crack, and it can also cause problems with adhesion on either the neck, or contact with the soundboard.

The largest problem with ebony is fret removal. When used as a fretboard, ebony can become very stiff and fragile, and when frets need to be removed and replaced, the fret slots can gaul or shatter. Caution and care have to be used when removing frets on an ebony fretboard, and this is usually done with the use of heat, by means of an iron, and very slow and careful removal of these frets. In many cases, when new frets are installed, they usually have to be glued into the fret slots, and then clamped individually so as proper adhesion can be assured.

Another disadvantage of ebony, is that it is not always readily available, and it's cost far out weighs rosewood.

Though there are definitely advantages and dis-advantages to both, rosewood seems to be the favourite choice by most makers for fret boards and bridge plates.

Next week we'll talk a bit about soundboards, and what woods they are made up of, and we will touch on some electric guitars as well, and what woods they are made up of.

Until then.....take care, and keep playing.

Brett McNaueal

Guitar electronics

Today I am going to talk a bit about electronics. I can get into great detail on this subject, but I really don't want to do that. There are varying opinions on the subject of what pickups are better than others, what guitar company wires their instruments the best, and on and on.

What I do want to talk about is what makes a guitar an electric guitar. Where does the sound come from, that you hear in your amplifier, and what makes that happen.

Basically, electric guitars and basses operate on the same principle. They have pickups, controls, switches, etc.

A pickup is a series of magnetic poles. These poles could not effectively 'pickup' the sound from the strings without a few important things. Number one is a fairly strong magnet, that is attached to the poles, 6 and 12 for guitar, and 4, 5, 6 and more for basses.

Number two is a coil of insulated wire with a start and finish end.

The insulated coil wire is wrapped around the magnetic poles, and the amount of wraps vary from one manufacturer to another.

There is an elite group of pickup manufacturers in todays market, and depending on what sound you are looking for, they will custom design a pickup that is just right for the sound you want to hear from your guitar.

That, in a nutshell is what makes the sound. Again, I am not getting into detail in this blog.

So, what happens from the pickup? How does that sound get to my amplifier?

The pickups convert the sound that the strings make on the guitar to an electronic signal. Based on how many pickups you have on an instrument, this is usually routed through a switch. The switch basically sends the signal from one, two, or three pickup guitars to a volume / tone potentiometer, or 'pot'. The potentiometer varies the amount of signal that you would want to go to your amplifier on to the guitar's output jack. So when you plug your guitar into your amplifier, you can control the volume both on your guitar and your amplifier.

Potentiometers are also referred to as 'faders', because that is what they do. There are also tone, or treble / bass potentiometers on your guitar. These vary the bass / treble, or 'tone' on your instrument through a small capacitor. On some guitars, there are either one, or two tone controls, and the same is true of the volume controls.

By raising and lowering the pickup, either closer to, or further away from your strings, one can add a lot of colour and tone to your 'sound'. There are factory specs for Fender, Ibanez, Gibson, PRS and many more. But ultimately you are the one that has to decide what sound your are looking for from your instrument.

Some pickups require an 'active' circuit, by means of a small on-board pre-amplifier. These Pre-amps are usually powered by the use of a 9 volt battery, which, like the pre-amp, is installed in the control cavity of the guitar.

Acoustic guitars can also be amplified by use of a pickup. Newer acoustics utilize 'piezo' technology. A 'piezo' is a tiny pickup that is designed to pickup vibration and resonance, as opposed to a magnetic signal.

Some of the new manufacturers of acoustic pickups have gotten incredibly good at making an acoustic sound amazingly like it should sound 'acoustically' by means of the use of these pickups.

The piezo pickup is also operated on battery technology, or 'phantom' power. Which, in simple terms is power that comes back into the instrument from an external device, like a DC power supply, sound board, or a digital interface.

The Gibson guitar company features a PAF (patent applied for) pickup on their guitars. These are also called humbucking, or balanced pickups. They are basically two single coil pickups that utilize two different magnets. The magnets are mounted in such a fashion that their respective poles attract (North-South and South-North) On the 6 string models, they feature 12 individual poles and on most PAF's one set of poles is covered by the chrome pickup cover. It is debatable as to whether or not the pickup cover is really required on these, and on some models it is dis-attached from the pickup.

Fender pickups, for the majority, have always been single coil. That just works for them. Like Gibson, and so many others, Fender has always maintained an 'if it ain't broke....' approach to their guitars. They may have changed their guitar designs and colours a bit, but their basic pickups are still the same.

Bass guitar pickups are built much the same as their electric 'cousins' but are usually overwound to better re-produce the lower frequencies of those bass notes. Basses also utilize both the humbucker, single coil and active designed pickups, but most of the bass guys I know prefer the simple old single coils, or active single coils. The Fender Precision Bass is still one of the biggest selling basses on the planet, and they are pretty much the same guitar they were when they were introduced in the 50's.

It's just that pickup technology has gotten so much better than the old ceramic or 'rare earth' magnets.

Newer designed magnets (Alnico 3&5) will outlast their counterparts, because the magnetism will not fade like it did on the old pickups, and as a result, neither will the tone.

Some guitar manufacturers use both humbuckers and single coil pickups on their guitars. This combination of pickups gives the player a wide range of sound. Not just volume, but different 'tonal' characteristics as well. Different pickups can totally change the sound of your guitar, and they can be an exact retrofit for your guitar. In other words, nobody will ever know but you.

I have my favourites, but again, that is not what this blog is about.

Hopefully this has given you a better insight as to how electric guitars work.

Have fun!

Brett McNaueal