Evertune Calculator: Achieve Perfect Guitar Tuning and Intonation

Use our advanced Evertune calculator to determine optimal string tension for your guitar setup. Ensure your Evertune bridge performs flawlessly by understanding the physics behind perfect pitch and tuning stability.

Evertune String Tension Calculator

String Tension Reference Table (Selected Note)

String Gauge (in)	Tension (lbs)	Evertune Module Suggestion

A reference table showing calculated string tension for various common gauges, helping you choose the right strings for your Evertune setup.

What is the Evertune Calculator?

The Evertune calculator is a specialized tool designed to help guitarists understand and optimize the string tension required for their Evertune bridge system. The Evertune bridge is a revolutionary mechanical system that ensures perfect tuning and intonation across the entire fretboard, regardless of string bends, temperature changes, or playing dynamics. Unlike traditional bridges, Evertune works by maintaining a constant tension on each string, effectively eliminating tuning instability.

This Evertune calculator specifically focuses on calculating the individual string tension based on critical parameters like scale length, string gauge, target pitch, and string material. Understanding these values is paramount for setting up your Evertune bridge correctly, selecting the appropriate Evertune module (F1, F2, F3), and achieving the unparalleled tuning stability that the Evertune bridge offers.

Who Should Use This Evertune Calculator?

• Guitarists with Evertune bridges: Essential for setup, string changes, and fine-tuning their instrument.
• Guitarists considering an Evertune bridge: Helps in planning string gauges and understanding the system’s requirements.
• Session musicians and touring artists: For whom tuning stability is non-negotiable.
• Recording engineers and producers: To ensure consistent pitch in studio environments.
• Anyone interested in guitar physics: A great way to learn about string tension and its impact on tone and playability.

Common Misconceptions about Evertune

While the Evertune bridge is incredible, there are a few common misunderstandings:

• It’s an auto-tuner: The Evertune bridge is NOT an electronic auto-tuner. It’s a purely mechanical system that keeps strings in tune once they are set.
• It eliminates all setup: While it greatly simplifies tuning, proper setup (including intonation, action, and Evertune module selection) is still crucial for optimal performance. The Evertune calculator aids in this setup.
• It’s only for metal: While popular in metal genres due to its stability with aggressive playing and low tunings, the Evertune bridge is beneficial for any genre where tuning consistency is valued.
• It makes string bending impossible: Evertune has a “bend zone” that allows for normal string bending. The setup determines how much bend is available before the system locks into perfect pitch.

Evertune Calculator Formula and Mathematical Explanation

The core of this Evertune calculator relies on the fundamental physics of vibrating strings. The tension of a string is directly related to its mass, length, and the frequency at which it vibrates. The formula used is a variation of the Mersenne’s laws for vibrating strings, adapted for practical guitar applications.

Step-by-Step Derivation of String Tension

The general formula for the fundamental frequency (f) of a vibrating string is:

f = (1 / (2 * L)) * sqrt(T / μ)

Where:

• f = Frequency (Hz)
• L = Vibrating Length of the String (Scale Length, in inches)
• T = Tension (lbs)
• μ = Mass per Unit Length (lb/in)

To calculate tension (T), we rearrange the formula:

1. Square both sides: f^2 = (1 / (4 * L^2)) * (T / μ)
2. Isolate T: T = f^2 * 4 * L^2 * μ
3. Combine terms: T = μ * (2 * L * f)^2

For practical units (T in lbs, L in inches, f in Hz, μ in lb/in), a conversion factor is needed. The constant 386.4 is used to convert from poundals (force unit in imperial system) to pounds-force. Thus, the formula used in this Evertune calculator is:

Tension (lbs) = (Mass per Unit Length (lb/in) * (2 * Scale Length (in) * Frequency (Hz))^2) / 386.4

Variable Explanations and Table

Understanding each variable is crucial for accurate calculations with the Evertune calculator:

Variable	Meaning	Unit	Typical Range
L (Scale Length)	The vibrating length of the string from nut to bridge saddle.	inches (in)	24.75″ – 27″
d (String Gauge)	The diameter of the string. Used to calculate mass per unit length.	inches (in)	0.007″ – 0.080″
f (Target Frequency)	The desired pitch (frequency) of the open string.	Hertz (Hz)	82.41 Hz (E2) – 329.63 Hz (E4) and beyond
ρ (String Material Density)	The density of the string material. Affects mass per unit length.	lb/in³	0.283 (Steel) – 0.321 (Pure Nickel)
μ (Mass per Unit Length)	The mass of one inch of string. Calculated as π * (d/2)² * ρ.	lb/in	0.00001 – 0.00020
T (Tension)	The force exerted on the string, measured in pounds.	pounds (lbs)	8 lbs – 30 lbs per string

Practical Examples (Real-World Use Cases) for the Evertune Calculator

Let’s look at how the Evertune calculator can be used for common guitar setups.

Example 1: Standard E Tuning (High E String)

Imagine you’re setting up a standard 6-string guitar with a 25.5″ scale length, aiming for standard E tuning.

• Scale Length: 25.5 inches
• String Gauge: 0.010 inches (common for a high E string)
• Target Note: E
• Target Octave: 4 (E4)
• String Material: Plain Steel

Using the Evertune calculator:

• Target Frequency: 329.63 Hz
• Mass per Unit Length: 0.0000222 lb/in
• Calculated String Tension: Approximately 15.0 lbs
• Recommended Evertune Module: F2 (Medium Tension)

This tension is well within the typical range for a high E string and would likely use an F2 Evertune module, which is the most common.

Example 2: Drop C Tuning (Low C String)

Now, consider a guitar tuned to Drop C, often used in heavier genres, with the same 25.5″ scale length.

• Scale Length: 25.5 inches
• String Gauge: 0.056 inches (a common heavy gauge for low C)
• Target Note: C
• Target Octave: 2 (C2)
• String Material: Nickel-plated Steel (core is steel)

Using the Evertune calculator:

• Target Frequency: 65.41 Hz
• Mass per Unit Length: 0.000699 lb/in
• Calculated String Tension: Approximately 17.5 lbs
• Recommended Evertune Module: F2 (Medium Tension)

Even with a much heavier gauge and lower tuning, the tension remains manageable. This demonstrates how the Evertune calculator helps in selecting appropriate string gauges to achieve desired tensions, which is critical for Evertune bridge setup.

How to Use This Evertune Calculator

Our Evertune calculator is designed for ease of use, providing accurate string tension calculations to optimize your Evertune bridge setup.

Step-by-Step Instructions:

1. Enter Scale Length: Input the scale length of your guitar in inches. This is the vibrating length of the string. Common values are 24.75″ or 25.5″.
2. Enter String Gauge: Input the diameter of the string you are using or planning to use, in inches (e.g., 0.010, 0.046).
3. Select Target Note: Choose the musical note you intend to tune the string to (e.g., E, A, D, G, B).
4. Select Target Octave: Specify the octave of the target note. For standard E tuning, the low E is E2, A is A2, D is D3, G is G3, B is B3, and high E is E4.
5. Select String Material: Choose the material of your string. This affects its density and thus the tension.
6. Click “Calculate Tension”: The Evertune calculator will automatically update the results as you change inputs.
7. Click “Reset” (Optional): To clear all inputs and return to default values.

How to Read the Results:

• Calculated String Tension (lbs): This is the primary output, indicating the force (in pounds) required to bring the string to the specified pitch. This value is crucial for Evertune bridge setup.
• Target Frequency (Hz): The precise frequency in Hertz corresponding to your selected note and octave.
• Mass per Unit Length (lb/in): An intermediate value representing the mass of one inch of your chosen string.
• Recommended Evertune Module: A suggestion (F1, F2, or F3) based on the calculated tension. This helps you select the correct Evertune module for optimal performance.

Decision-Making Guidance:

The tension value from the Evertune calculator is key to a proper Evertune setup. If your calculated tension is too low for a given string, it might feel “floppy” or not engage the Evertune module correctly. If it’s too high, it might feel stiff, be difficult to bend, or put excessive stress on the guitar. Aim for a tension that feels comfortable for your playing style and falls within the recommended range for your chosen Evertune module.

Key Factors That Affect Evertune Calculator Results and Bridge Performance

Several factors influence the string tension calculated by the Evertune calculator and, consequently, the performance of your Evertune bridge. Understanding these helps in optimizing your setup.

1. Scale Length: A longer scale length (e.g., 27″ baritone) will result in higher tension for the same string gauge and pitch compared to a shorter scale (e.g., 24.75″). This is why baritone guitars can handle lower tunings with relatively lighter gauges. The Evertune calculator clearly shows this relationship.
2. String Gauge: Thicker strings (higher gauge) have more mass per unit length, leading to higher tension for the same pitch and scale length. This is the most common way guitarists adjust tension for different tunings. The Evertune calculator highlights the impact of string gauge.
3. Target Pitch/Tuning: Lowering the target pitch (tuning down) significantly reduces string tension. This is why heavier gauges are often needed for drop tunings to maintain a playable tension. The Evertune calculator helps balance gauge and pitch.
4. String Material: Different string materials have varying densities. For example, pure nickel strings are denser than steel, resulting in slightly higher tension for the same gauge and pitch. This is a subtle but important factor considered by the Evertune calculator.
5. Playing Style: While not directly an input for the Evertune calculator, your playing style influences your preferred tension. Aggressive players might prefer slightly higher tension for better attack and less fret buzz, while those who bend a lot might prefer slightly lower tension (within the Evertune’s bend zone).
6. Evertune Module Selection: Evertune offers F1 (low tension), F2 (medium tension), and F3 (high tension) modules. The calculated tension from the Evertune calculator helps you choose the correct module for each string to ensure it operates within its optimal range. Mismatched modules can lead to improper Evertune functionality.
7. Bridge Setup and Intonation: While Evertune handles intonation exceptionally well, the initial setup of the bridge (saddle height, spring tension adjustment) is critical. The Evertune calculator provides the target tension, which is a starting point for these adjustments.
8. Temperature and Humidity: Evertune bridges are designed to compensate for environmental changes, but extreme fluctuations can still have a minor impact. Understanding the baseline tension with the Evertune calculator helps in diagnosing any unusual behavior.

Frequently Asked Questions (FAQ) about the Evertune Calculator and Bridge

What is an Evertune bridge?

An Evertune bridge is a patented, all-mechanical guitar bridge system that keeps your guitar perfectly in tune and intonated across the entire fretboard, regardless of string bends, temperature changes, or playing dynamics. It achieves this by maintaining constant tension on each string.

How does the Evertune calculator help with Evertune setup?

The Evertune calculator helps you determine the ideal string tension for any given string, scale length, and tuning. This information is crucial for selecting the correct Evertune module (F1, F2, or F3) for each string and for fine-tuning the individual spring tension on the bridge to ensure optimal performance and feel.

Is the Evertune calculator only for electric guitars?

Yes, the Evertune bridge is primarily designed for electric guitars. While the underlying string tension physics applies to all stringed instruments, the Evertune system itself is integrated into electric guitar bodies.

Can I use any string gauge with an Evertune bridge?

While Evertune is highly versatile, the choice of string gauge must be appropriate for your desired tuning and scale length to achieve a playable tension. The Evertune calculator helps you find this balance. Each Evertune module (F1, F2, F3) also has a recommended tension range, so matching your string gauge to the module is important.

Does Evertune affect my guitar’s tone?

Some players report a slight change in sustain or resonance due to the Evertune bridge’s mass and mechanical nature. However, the primary benefit of perfect tuning and intonation often outweighs any perceived tonal differences for most users. The Evertune calculator focuses on the physics of tension, not subjective tone.

What are the different Evertune modules (F1, F2, F3)?

Evertune modules are interchangeable spring-and-lever mechanisms designed for different tension ranges. F1 is for low tension (light gauges, very low tunings), F2 is for medium tension (standard gauges, common tunings), and F3 is for high tension (heavy gauges, high tension setups). The Evertune calculator provides a recommendation based on your inputs.

How do I choose the right string gauge for my Evertune setup?

Use the Evertune calculator! Input your scale length, target note, and octave. Then, experiment with different string gauges until you find a tension that feels comfortable for your playing style and falls within the recommended range for your Evertune module. Generally, heavier gauges are needed for lower tunings.

Does Evertune require special strings?

No, Evertune bridges work with standard guitar strings. The key is to choose strings with appropriate gauges for your desired tuning and to set up the bridge correctly, which the Evertune calculator assists with.

Related Tools and Internal Resources

Explore more tools and guides to enhance your guitar knowledge and setup:

• Guitar Scale Length Calculator: Understand how scale length impacts playability and tone.
• String Gauge Comparison Tool: Compare different string sets and their characteristics.
• Guitar Tuning Guide: Comprehensive guide to various tunings and their applications.
• Guitar Intonation Guide: Learn how to set up perfect intonation on any guitar.
• Guitar Setup Checklist: A step-by-step guide for maintaining your guitar.
• Fretboard Note Finder: Quickly identify notes across your guitar’s fretboard.

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// Let's use a very basic canvas drawing for the chart, not Chart.js.

// Re-implementing chart drawing without Chart.js
function updateChartNative(scaleLength, targetNote, targetOctave, stringMaterial, currentGauge, currentTension) {
var canvas = document.getElementById('tensionChart');
var ctx = canvas.getContext('2d');

// Clear canvas
ctx.clearRect(0, 0, canvas.width, canvas.height);

if (!currentGauge || !currentTension) {
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ctx.fillText('Enter valid inputs to see chart', canvas.width / 2, canvas.height / 2);
return;
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var gauges = [];
var tensions = [];
var labels = [];

// Generate data points around the current gauge
for (var i = -3; i <= 3; i++) { var gaugeStep = 0.001; var gauge = currentGauge + (i * gaugeStep); if (gauge > 0.005 && gauge < 0.1) { gauges.push(gauge); labels.push(gauge.toFixed(3)); var density = stringDensities[stringMaterial]; var targetFrequency = getFrequency(targetNote, targetOctave); var stringRadius = gauge / 2; var massPerLength = Math.PI * Math.pow(stringRadius, 2) * density; var tension = (massPerLength * Math.pow(2 * scaleLength * targetFrequency, 2)) / 386.4; tensions.push(tension); } } var maxTension = 0; for (var j = 0; j < tensions.length; j++) { if (tensions[j] > maxTension) {
maxTension = tensions[j];
}
}
maxTension = Math.ceil(maxTension / 5) * 5; // Round up to nearest 5 for y-axis

var padding = 50;
var chartWidth = canvas.width - 2 * padding;
var chartHeight = canvas.height - 2 * padding;
var barWidth = chartWidth / (gauges.length * 1.5); // Adjust bar width and spacing

// Draw Y-axis
ctx.beginPath();
ctx.moveTo(padding, padding);
ctx.lineTo(padding, canvas.height - padding);
ctx.strokeStyle = '#333';
ctx.stroke();

// Draw X-axis
ctx.beginPath();
ctx.moveTo(padding, canvas.height - padding);
ctx.lineTo(canvas.width - padding, canvas.height - padding);
ctx.strokeStyle = '#333';
ctx.stroke();

// Draw Y-axis labels and grid lines
ctx.fillStyle = '#333';
ctx.font = '12px Arial';
ctx.textAlign = 'right';
var numYLabels = 5;
for (var k = 0; k <= numYLabels; k++) { var yValue = (maxTension / numYLabels) * k; var yPos = canvas.height - padding - (yValue / maxTension) * chartHeight; ctx.fillText(yValue.toFixed(0), padding - 10, yPos + 4); if (k > 0) {
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ctx.lineTo(canvas.width - padding, yPos);
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ctx.textAlign = 'center';
ctx.fillText('Tension (lbs)', padding - 30, canvas.height / 2, 40); // Y-axis title

// Draw X-axis labels and bars
ctx.textAlign = 'center';
for (var l = 0; l < gauges.length; l++) { var xPos = padding + (l + 0.5) * (chartWidth / gauges.length); var barHeight = (tensions[l] / maxTension) * chartHeight; // Draw bar ctx.fillStyle = (Math.abs(gauges[l] - currentGauge) < 0.0001) ? '#004a99' : '#a0c0e0'; ctx.fillRect(xPos - barWidth / 2, canvas.height - padding - barHeight, barWidth, barHeight); // Draw X-axis label ctx.fillStyle = '#333'; ctx.fillText(labels[l], xPos, canvas.height - padding + 20); } ctx.fillText('String Gauge (inches)', canvas.width / 2, canvas.height - padding + 40); // X-axis title // Chart Title ctx.font = '16px Arial'; ctx.fillStyle = '#004a99'; ctx.fillText('Tension vs. String Gauge for ' + targetNote + targetOctave + ' (' + scaleLength + '" Scale)', canvas.width / 2, padding / 2); } // Initial calculation on page load window.onload = function() { calculateEvertuneTension(); }; // Override the updateChart function to use the native canvas drawing updateChart = updateChartNative;