Several things can cause tonal changes in the lowest strings, including –

If the string saddle is far back, due to intonation, it can cause the (stiff) low strings to round the front edge of the saddle poorly, which means that the string is not lying solid on the front part of the bridge, and can (in some cases) create a subtle muddiness (because the string length is changing very slightly as the string vibrates). Rare but can occur.

The action, height, can produce muddiness occasionally. Experimenting with higher or lower action by adjusting the height of the saddle may make a difference. (Be sure to adjust truss first to get flat fretboard if it has moved; see Megatar Owner’s Guide for correct trussrod adjustment procedure. Anyone can download a free copy in the documents section of the Megatar main website.)

Your playing, your touch, can make a difference, though it’s hard to specify.

Your particular amp or effects chain can make a difference. Try others at the guitar store to see if that’s it. Try removing all effects. Most likely problem effects would include chorus, and certain kinds of reverb. ‘Helpful’ effects would include the ‘aural exciter’ type of effect. And when your EQ kills all the highs, the ear cannot track low notes well, and can in some cases be perceived as muddiness.

If you’re tuning to something other than standard notes, then you may not get the best tone because the gauges and tension may not be optimum. If using a non-standard tuning, you may have to use non-standard gauges, to change the tension, to get the best sound. Careful experiment is the only way to find out.

Of course, do realize that all tapping instruments have a different sound than a plucked bass. If you ‘pluck’ your bass with a pick right next to the bridge saddle, you are triggering the string very similar to what tapping does. And this will not have the same soft pop as a bass plucked with vigor near the fretboard.

Other brands/kinds/gauges of strings — we’ve not experimented with other types. When designing, we wanted to use the most commonly available type of string, so that players could easily find strings that would work well. For this reason it’s difficult to say how other types of strings will work, and so cannot report much about that. If using other types of strings, you are the pioneer, and so you’ll need to experiment and compare.

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Not really. Of course, the better you tune up, the better you will sound. However, the Feiten system is installed by making small adjustments to string length at both ends of the strings. On one end, the nut (or zero fret) is moved slightly. On the other end, the string saddles are adjusted to +/- a few cents here and +/- a few cents there.

The result is kind of like the ‘stretch tuning’ commonly used on pianos to make them sound more ‘in tune’ to our ears. Pianos have used this advanced ‘stretch tuning’ system for 700 years. But guitars never had such an adjusted tuning until Buzz Feiten, a southern California studio musician, developed the system.

A guitar has to have adjustments in two dimensions. Adjustments *along* the length of the string, and adjustments *across* the strings (one string against another). It’s not a perfect system, but it sure sounds a lot sweeter than no system at all!

Because the adjustments are already done, at both ends of the strings, you can tune up any way you wish.

So tune up using any method you like — tuner, ear, harmonics, beats — and it will sound better than a normal guitar, because the string saddles have offsets, and each string is biased a little against the other strings. There is a suggestion in the Mobius Megatar Owner’s Guide for one way to tune up, but you can tune it any way you wish, and it will sound more ‘in tune’ than would a normal guitar tuned up in the same way

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Experimentation is your friend. Here are some possibilities –

RECEIVING BROADCAST HUM

There is something in the environment which is “broadcasting” RFI in the room where your equipment is located. Common sources of Radio Frequency Interference include motors (vacuum cleaners, refrigerators, and automobile distributors), and transformers (high-intensity lamps, fluorescent lights), and from big magnets like speaker coils or television sets. The sound from autos are likely to vary in frequency. The sound from lamps and lights and refrigerators are likely to be be consistent, and at 60 cycles per second, which is what we normally call ‘hum.’

The RFI can be picked up either by strings (antennas) or by pickups (coils) as the signal is induced into the circuit created by the guitar and its parts, or into the cord (usually not possible if cord is properly shielded on both the guitar and the amp end), or into the amp.

The RFI is then *not* filtered by the humbucking pickups. Normal hum *is* filtered by humbucking pickups. In our shop, when we build the Mobius Megatar Tapping Basses, we do our lab work two feet under a fluorescent light, just to ‘hear’ if there is a problem, and this hum is normally filtered out.

So the best way I know to get an idea that strong RFI in the environment is some part of the culprit is to get the hum going, and then change the orientation of the instrument. If you hear hum while the instrument is flat on the table, but not when it’s upright, or if you hear hum while the instrument is upright facing east but not when it’s facing north, then probably there is a strong RFI source in your environment. Remember that it may be behind a wall or a ceiling or floor. Wood and sheetrock is no barrier to Radio Waves.

If the instrument seems the same in all orientations, then consider the cord and the amp. Try moving them to a different room or part of the room.

TOUCHING METAL

Sometimes you will hear hum, and then you touch the strings with your hand and the hum vanishes. Or you touch the (metal) tone/volume knobs, and the hum goes away. I’ve been told this has something to do with the ‘capacitance’ of the human body, and I think that means that the body soaks up alternating signals. But that’s too vague. It doesn’t get us anywhere. I suspect this is a meaningful clue; I just don’t know what it means.

A GROUND LOOP

Hum can be caused by something called a ‘ground loop.’

We can think of an electrical power plug as have a left and a right prong, or we can think of a signal having a signal and a ground wire. If you’re not using two amps then the question of their having the same side (left or right) as the ‘ground’ should not be an issue, though it is *possible* that an input jack on your mixer *might* be reversed from the others ones *if* repair work was ever done on the mixer.

Likewise, if some of the inputs on the mixer are for ‘line level’ like synths, and others are specifically built for magnetic inputs like guitar, or others are specifically for mikes (and either with or without phantom power) then it is possible that all inputs are not equal. Sometimes there are switches associated with the inputs.

HUM SPECIFIC TO TAPPING GUITARS AND BASSES

On specialty tapping instruments, like the Chapman Stick, Warr Guitar, and Mobius Megatar, usually two outputs are provided. One for the bass pickup(s) and one for the melody pickup(s).

In Mobius Megatar and other instruments that I’ve seen, the bass and the melody have the same ground.

Normally, the ground is common throughout the guitar — The pickups cavity is grounded all around, the pots and pickups and outjack are all grounded to the same place. Even the strings are grounded to the same place. Therefore, the stereo cord goes into two mono cords, and the two mono plugs — one for bass, and the other for melody strings — have the same ground.

On Chapman Stick or a Mobius Megatar tapping bass, these output mono jacks, have signal on the metal tip, and ground on the metal sleeve of the jack, and it’s the same ground all the way back to the pickups and guitar components and the shielded cavity.

Therefore, unless one uses a mutant and miswired stereo cable, the sleeves of the two mono jacks should both be ground. A voltmeter connecting the two sleeves should show zero resistance.

HUM COMING FROM MIXER OR AMP WITH TWO MONO CABLES

But if a hum is coming from any mixer or amp when two common-ground mono cables are plugged into two inputs, it might be suggested that there is either (a) a 60-cycle induced hum that has been induced across the two signal tips; or (b) that the signal/ground is reversed on one of the mixer/amp signal paths relative to each other.

This article is not capable of analyzing or diagnosing the device you are using, but a fast way to find out if that’s the source of trouble is — carry your Megatar or Chapman Stick to Guitar Center. plug it into a bass amp, and plug it into a Guitar amp, and play it. No hum? Then there is nothing wrong with the guitar or the cable.

Get them to stop the kid playing Stairway to Heaven with his amp set to eleven while you do this test.

ELECTRICAL OUTLETS AT YOUR HOUSE OR ON THE GIG

The electrical outlets in the wall are ’spozed to have proper grounding. However … maybe they don’t. Even if they have three prongs, maybe somebody just stuck those part on the wall and maybe that third, grounding wire isn’t connected up to an actual ground.

If you have more than one amp or effects, best to plug them all into the same outlet. Or carry your own multi-outlet strip.

An easy way to create a ground loop in the power is to have two devices that have two prong plugs. Plug one in rightways and the other one reversed. Just about nearly always you’ll hear hum, and with the right equipment you can shock yourself seriously. Not even a joke.

Plugs these days are ’spozed to have one fat prong and one thin one, so they cannot be reversed, but it doesn’t always work. And remember … some human may have wired up that plug. Oops.

SINGLE COIL PICKUPS

Single-coil pickups are part of a radio-receiver circuit. Remember the coil of wire you made when you built a crystal radio in cub scouts? Signals can be induced into coils rather easily. They are natural ‘receivers.’ Any source of RFI is likely to sound through single-coil pickups. Darn.

Specialty touchstyle basses like the Chapman Stick, Warr Guitar, and Mobius Megatar, designed for two handed tapping, will usually have the instrument’s gain turned higher than a standard guitar, because we’re just tapping gently on the string instead of strumming like all get out.

Turning the gain up increases the signal, but also boosts the background noise, including hum, as well, so dealing with hum may require a bit more attention, if you want a quiet sound.

SORRY INSTRUMENT DESIGN

Cheap instruments, in some cases imported strat knockoffs, sometimes do things so sloppily that they do not have any shielding around the electronics. The cavity around the electronics and pickups should have a solid conductive material all around these components. It’s called a ‘Faraday Cage’ after Michael Faraday I suppose, and it keeps those nasty vibes from annoying the components.

I have heard, but don’t know whether it is true, that the basic Fender Stratocaster design has ground-loop errors in the basic design. I am dubious. Not Leo! But for certain, a guitar maker could make a blunder, I suppose. If it’s on one guitar but not another, take it to a whiz guy.

SORRY CABLES

The teeny signal is running on a wire across (to the signal) a vast distance to get to the amp. Lots of signals in the air could disturb it, but it is ’spozed to have a big fat woven wire all around it — again a Faraday Cage — protecting it from bad vibes. And this big fat woven wire would optimally be connected to ground on the tapping guitar, and to ground at the amp.

But is it?

A fancy name and expensive price tag may not be the best cable. However, again, a trip to Guitar Center with the noisy guitar and cable, and if you try some of their cables and the noise goes away … it’s a definite clue.

[This post adapted with permission from the Reducing Hum article at the Two-Handed Tapping website.]

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There is also the popular bass-strings tuning we call ‘Inverted Fifths’ which has some enthusiasts among touch-stylists. Yet you can still play the ‘Easy Touch-Style’ method in that tuning. Because this tuning is popular, upon request we will provide instruments with bass strings tuned this way, and the method book covers Inverted Fifths tuning as well as our standard tuning.

If you’re an existing bass player or guitar player taking up touch-style we suggest you try the standard ‘Bass Bottom’ tuning, because we think you’ll find it familiar, and it seems better for many types of music. And if you’re just starting out, we still suggest you try standard ‘Bass Bottom’ tuning. In our opinion, it’s much simpler, and faster to learn.

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It’s the same idea. You don’t play them all at once. In fact, we start out just playing three strings just above fret two. If you play guitar or bass, your left hand already knows how to fret these notes, and you don’t need to pick or strum, so you just touch the string to the fret and it plays. Now here’s where you get lucky …

All of your ‘left hand learning’ was really just training your head, and your right hand is wired into the same head. What that means is that whatever your left hand knows, your right hand almost knows already. You’ll discover that your right hand can very quickly be playing like your left hand.

If you’ll start out with our standard ‘BassBottom’ tuning, you’ll notice that the left-hand set of strings are tuned exactly like a standard six-string bass. And the notes on the right-hand set of strings just above fret twelve are *identical* to the left-hand notes just above fret two. This means that you can play both hands identically; in fact you can train them simultaneously.

This method of play is somewhat easier to learn than guitar because the straight fourths tuning makes unnecessary learning additional scales and chords to deal with the ‘B’ string like on guitar. And it’s a little easier than piano because piano requires you to operate your left hand and right hand differently to move up a scale. In this method of play, you operate both hands exactly identically. The BassBottom tuning gives you the only two-handed instrument in the world which lets you play two-handed and operate both hands identically.

Pick up a free preview copy of our method book in the ‘Documents‘ section of this website — or subscribe to our free newsletter and we’ll send you the complete book as a bonus — and you’ll see how surprisingly easy it can be. The book is written so you can try it on any six-to-eight string instrument, and it even works with the unusual ‘Inverted Fifths’ bass-strings tuning.

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