Les Paul Guitar Setup Guide

Today I’ll be performing a full setup on a Les Paul style guitar.

If your Les Paul seems a little out of whack then follow the guide carefully and together we’ll get her singing again.

Firstly you should tune your guitar to your usual playing preference. I always recommend tuning in playing position whenever possible as tuning the guitar as it lies on its back can often differ.

• 1. Check & adjust neck relief.

A good starting position for any setup is to check the guitars neck relief. Gibson’s recommended method for accomplishing this is to place a capo slightly behind the first fret then press down on the low E (thickest) string just behind the 14th fret with your finger. This allows the relief to be accurately adjusted without any influence from the nut or bridge.

Now, using your free hand, slide a 0.25mm (0.010″) feeler gauge between the low E string and the top of the 9th fret. If you don’t have a feeler gauge then a standard business card works great. If the gap is to high the truss rod needs to be tensioned. If the gap is too low then the truss rod should be loosened. Twist the truss nut clockwise to tighten and counter-clockwise to loosen in quarter turn increments until the gap is perfect.

Once step 1 is complete remove the capo and tune the guitar again.

• 2. Check & adjust string action.

To measure the action of the guitar we will need our feeler gauges again. If you don’t have any feeler gauges then a small mechanics ruler should suffice.

Allow the strings to sit in their natural position and measure the distance between the bottom of both the high and low E strings and the top of the 12th fret. The recommended heights should be as follows;

• Top/High E string (thin) = 1.6mm (4/64″)
• Bottom/Low E String (thick) = 2.4mm (6/64″)

Each side of the bridge has a simple screw adjuster, which when turned, will adjust the height of the E string on the same side. Tightening the adjuster clockwise will lower the string and loosening the adjuster anti-clockwise will raise the string. Make half turns then measure until the action is correct on each of the E strings.

Once finished tune the guitar and take the measurements again to ensure both are still correct. If not repeat until the action is correct whilst perfectly tuned.

• 3. Adjust the string intonation.

If you look at the bridge you will see that each of the strings sits on a small saddle. You will also notice that each saddle has a small adjustment screw which is what is used to control intonation.

Plug your chromatic tuner into your guitar and starting with the low E string ensure that it is perfectly in tune. Now hold down the 12th fret and try again, it should match the open string E note perfectly. If the note is too sharp you will need to lengthen the string by adjusting the saddle towards the bottom of the guitar. If the note is too flat then you will need to shorten the string by adjusting towards the neck. Adjust in half turn increments, re-tuning the open string after each saddle adjustment.

Once the open and 12th fretted notes match perfectly we can move on to the A string. Repeat this process until all strings are completed. Afterwards give each string 2-3 tugs upwards, between the pickups,  to ensure everything is seated nicely. Retune again and the intonation will be correct.

• 4. Check for fret buzzing.

Once your guitar has been setup I always like to check for buzzing. This is simply checked by playing each fret, one by one, a string at a time. If you are experiencing fret buzzing after correctly setting the action and neck bow then your next step should be to check for a raised fret using a fret rocker.

If your frets are all perfectly even then the next most common cause of buzzing is a worn or damaged nut. Replacing the nut should hopefully eliminate the problem. The recommended string heights from the first fret should be approximately as follows:

• Low E: 0.030″
• A: 0.030″
• D: 0.022″
• G: 0.022″
• B: 0.015″
• High E: 0.015″

Sometimes nut slots simply need a little lubricant when they are causing issues but if the slots have and broken edges the nut will need replacing. On occasions nut problems can be caused by changing string gauges so ensure that only 1/3 of the string is exposed from the nut and that the other 2/3 is snugly sat inside its slot.

There is a multitude of products available to assist with string buzzing caused by the nut, the most popular of which are graphite powder and Big Bend’s Nut Sauce. Personally whenever changing strings I always rub each slot with a standard sharpened pencil.

• Pickup Height.

This all comes down to personal preference and will also vary depending on the type and brand of your pickups. The closer the pickup pole is to the bottom of the string, the hotter the signal and the lower the pole is away from the string, the cooler the signal. Depending on how hot your pickups are you will want to adjust this to your own liking however it is always best to start with the factory recommended heights and work your way from there by ear.

The pickups are adjusted by loosening and tightening the central screws on either side of the pickup covers. To measure hold your finger down on the guitars last fret and place a small mechanics ruler on the poles to measure its distance from the bottom of the string. Do this on the first and last poles and measure the height for the high and low E strings which should match each other perfectly.

Les Paul’s will normally come pre fitted with stock Humbuckers however, you will also occasionally find models fitted with P90’s. The factory recommended heights are as follows;

• Neck Humbucker: 2.4mm (3/32″)
• Bridge Humbucker: 1.6mm (1/16″)
• Neck P90: 4mm (5/32″)
• Bridge P90: 2.4mm (3/32″)

Note that P90’s are hard to give any specific recommended setting as they are far more sensitive to feedback issues. When adjusting P90’s set them to the above heights as a starting point and fine tune accordingly.

In the world of guitars there are no settings written in stone. It all comes down to personal preference and experience. Getting a feel for your instrument and figuring out what works best is part of each guitarists secret formulae to achieving their “perfect” tone. You will often see some of the greatest tones coming from the most poorly setup, terribly maintained and bashed up guitars you will ever see, but it just works for that player. It’s all about finding the sweet spot between player and guitar that can only be perfected through experience.

If you have any different methods, corrections to my settings or other tips please be sure to leave a comment. I’m always looking to improve upon my own setup.

VOX AC15C1 Amp Upgrade

The great prices of the modern AC15 and AC30 custom models (C1) is bringing VOX back into the limelight of affordable practice amps. The base budget models come pre fitted with Celestion Greenback speakers but for around an extra £100 you can buy the premium model fitted with The all famed Celestion Blue speaker.

Unfortunately Celestion speakers are not quite what they used to be when they were manufactured in the U.K. and have a very high pitched shrill sound which many owners attempt to counter by snipping the bright caps however, this sparkle is part of the VOX charm so I’d recommend leaving them as is until completing the following steps as I found that the caps weren’t the cause of the sharp treble.

I purchased a completely stock, used, AC15C1 from eBay for £375 to begin my project. After a bit of a clean I was surprised that it was in almost new condition.

1. Glass Tube Valves

My first step was to remove the stock, Chinese made tubes. I have nothing against the quality of these budget tubes but I’m going for a vintage creamier sound so fitting a better quality set seemed a good investment.

After researching the commonly known brands I was still not satisfied with my options so decided to go with a full set of tubes from the legendary tube manufacturer, Peter Watson’s company, PM Components. They produce extremely high quality tubes with great vintage British tones and have recently been famed for their amazing 12AX7 HG (high gain) tube which is one of the best I’ve used to date.

Peter Watson’s 12AX7 High Gain valve

The 12AX7HG is fantastic in V1 position alongside a matched pair of their awesome EL84’s, their 12AX7LM for the phase inverter and 12AX7A for reverb position. This is one of the cheapest mods you can make with an immediate improvement over the stock Chinese tubes.

Assuming you are looking at the back of the amp, going from left to right, the first preamp tube (the one with the shield) is v1, and is thefirst gain stage for both the normal and the top boost channels. The second is v2, which is the second gain stage for the top boost channel. The third (the one closest to the power tubes) is the phase inverter.

2. Speaker Replacement

As I previously pointed out, the stock Celestion speaker is no longer British made, but is instead manufactured in China. Unfortunately they can be quite shrill which people often try to counter by snipping the bright caps. Personally I believe it’s better to solve the issue at the core of the problem by replacing with an actual British made Celestion.

Since vintage British Celestion blues are so expensive and rare I went in search for a cheaper alternative and was happy to find a modern Celestion speaker, manufactured in the U.K, custom designed and manufactured specifically for Bad Cat amplifiers. These speakers combine the percussive low end of a G12H30 but with the creamy cone response of a vintage Bulldog Alnico.

This 65w 100db speaker pulls all the mids together, provides solid bass and sprinkles a smooth creamy layer over the top. This gives a solid upgrade over the stock speaker and is probably the best pound for pound upgrade you can make.

I picked mine up from the good fellows at coda-music.com. 😁

3. Reverb Tank

The stock Accutronics & Belton BS3EB3C1B just didn’t do it for me. Anything past around half way would start to sound very thin and distant which was a deal breaker for me. I removed the tank and replaced it with a MOD 8EB2C1B which was an immediate improvement. This may have something to do with how the transducers on MOD tanks are wired directly to their respective RCA jacks rather than being connected to a detachable plug.

Mod 8EB2C1B Reverb

That’s all I did up to this point however there are huge amounts of mods for this amp. I felt no need to snip the bright caps after performing the above steps and decided to leave them standard however, that is the next most popular step taken by modders.

4. Bright Cap Mod

I personally found that the sharp tinny sound of the stock C1 was caused by the Chinese Celestion and didn’t need to perform this mod however, for many this is the first step they take due to the simplicity, zero cost and immediate effectiveness of the modification.

I’d recommend only performing the bright cap mod if you still find the treble too sharp after replacing the tubes and speaker.

The “bright cap” is a tiny capacitor which is responsible for the famous Vox chime. Some find that it gives way to much treble on a stick AC15C1 and report that removing this provides an immediate fix. You can simply snip the legs to remove the cap or desolder properly invade you ever wish to fit it again. The more experienced electricians amongst us can even fit a toggle switch to turn the cap on and off at will. I will cover this switch mod in a future article.

Simply remove this cap

I’m really happy with the results of this project. I was surprised to find a huge community of “modders” specifically for this amp, with an enormous list of simple and technical modifications to improve upon it. These guys are far more knowledgeable with electronics than myself however, I do have a very good ear and feel no need for further mods. Further modification may improve upon the tone even more but I personally believe that going further than the steps above is pointless and simply means that your just not happy with the amp and are trying to completely change its sound. If so you may be better simply replacing it for something better suited.