On Monday after work, I headed for the hills with my guitar and camera, hoping to get a few good shots for my newly redesigned website. I raced up the steep, overgrown path to reach the top in time for golden hour. We’ve had a lot of rain this year and the hillside was unusually lush and green. More
- Gear Diary
- Guitar Circuit Wiring
- Guitar Potentiometers
- Guitar Preamp Cable
- Guitar Tone Capacitors
- Guitar Treble Bleed
- Pedal Building
- Photo and Video
- Semi-Hollowbody Electronics
- VOX AC15
A couple weeks ago, my birthday rolled around, and I ended up purchasing a new Gibson 2013 Les Paul Studio. The Gibson is twice the price of my Epiphone and nearly ten times the price of the Monoprice. What are the differences? How do they stack up? More
My Epiphone Les Paul Tribute Plus came with Grover locking Rotomatic tuners. These tuners work phenomenally well. They stay perfectly in tune no matter how much I bend and beat on the strings- and adjustments are smooth and accurate.
On the Rotomatics, you just insert the string, and give it a wind, and an inner-cam rotates, locking the string into place under the string’s own tension. I always feel a little uncertain when changing strings on these because the process is a bit different from other tuners. Here are the instructions from Grover:
1. Turn tip of string post until it clicks into place. This aligns string post holes.
2. Note string hole is off center. Turn knob to rotate post until string hole is positioned away from knob. Thread string up through bottom of hole and pull firmly. See drawing.
3. Turn to begin tuning. At first, only inner “Locking Cam” is turning, securely locking the string. Once the string is locked, outer post will turn.
4. Bring string to pitch.
I was at a local music shop (ok, I admit it was Best Buy), and out of curiosity, I picked up an absurdly expensive Gibson Les Paul Traditional from the wall-o-guitars, plugged it into a Vox Night Train, and gave it a spin. I’ve never really given the Les Paul guitars much attention. Despite their iconic status and near ubiquity, I’ve always thought the Les Paul was just too heavy to consider. But… More
The set list ranged from some classic rock, right up to the present:
- Shine On – Peter Frampton
- Get Back – Beatles
- Penny On The Train Track – Ben Kweller
- Taste of Danger – Jonatha Brooke
- Stop – Joe Henry
- Wonderwall – Oasis
- Animal – Neon Trees
- Cough Syrup – Young the Giant
- Perfect Situation – Weezer
- I’m Sorry – Charles Besocke (original)
- Don’t Take It Easy – Laura Whitmore (original)
- The Only Exception – Paramore
- Help Me (She’s Out of Her Mind) – Stereophonics
- Level – Raconteurs
- Revelry – Kings of Leon
- Chocolate – Snow Patrol
- Loving Cup – Rolling Stones
- Had Me A Real Good Time – The Faces
I’m playing lead guitar on all of these, and some definitely push the limits of my abilities- so it’s been a great challenge. Also, and rather more nerve-wrackingly, I sing on most of the songs- mostly harmony with our lead singer Laura Whitmore, but I also had to sing lead parts on a couple songs. I’ve never been thrilled with the timbre and range of my voice, so I spent a lot of time working on the songs. As with anything, it’s definitely true that the more you practice, the better you get, but I have a looooong way to go. I’ll be writing more about voice training in another post.
A reader recently asked me a question about the low pass filter in a guitar tone circuit:
Will a 250k tone pot with a .02uF capacitor sound the same as a 500k pot with a .01uF capacitor (all else being equal)?
This is an interesting thought experiment, and the answer is simultaneously obvious and non-intuitive.
At first glance, you might be tempted to look at this standard low-pass filter schematic (borrowed from the LPF wiki), and the associated formula for cutoff frequency as 1/2piRC, and conclude that the two circuits would behave identically (since 250k*.02uF is the same as 500k*.01uF). However, the problem there is that the R in the formula is not the tone pot! That R is really the internal resistance of the guitar, or the resistance of the pickup.
In the tone circuit, the pot actually sits above the capacitor C, but below the branch to the output Vout, as shown at left. So, the formula for the cutoff frequency is more complex. In this analysis by a guitarist/mathematician named Bill, he suggests a formula for the cutoff frequency as follows:
How’s that for insanely non-intuitive?! Bill points out that the lower square root term only works with tone resistances less than about 20k (since otherwise the value would go negative producing imaginary numbers in the square root), thus explaining the often limited useful range of tone pots, and why log taper pots are more useful for tone than linear. Nevertheless, this seems to be an over-idealized formula, since in practice, I do see more variation in the tone pot even at higher resistances. This formula doesn’t seem to capture the full complexity of the reactive network made up of pickup inductor, and overall circuit resistance and capacitance (including cable capacitance).
Ok, so math is clearly the wrong way to think about this!! Too complicated! Back to the original question. Let’s think of it more simply. Imagine you turn both pots down to zero- you’re basically eliminating the variable resistance pot and wiring the cap directly to ground. Of course, the larger capacitance .02uF will sound darker than the .01uF. So they’re obviously not equivalent circuits.
Next up, experiment! Grab a couple pots, caps and some alligator leads and try it out! You’ll find that they do indeed sound quite different. The larger capacitance with the smaller pot resistance sounds darker, no matter how you slice it, when compared to the 500k pot and .01uF cap. Even with both pots up full, the larger capacitance with the smaller pot sounds a bit darker.
This all begs the question, why do guitar manufacturers often pair a 250k tone pot with a .047uF cap, versus the .022uF cap with 500k pots? The former will produce a darker sound both because of the larger capacitance but also because of the increased load on the pickup from the smaller resistance. “Double whammy” as Bill points out at the end of his paper.
Following last year’s All About Pickup Magnets, here’s another excellent article on guitar pickup magnets, courtesy of Pete Biltoft at Vintage Vibe Guitars. Thanks Pete for the permission to post this here!
In this article, Pete consolidates his own expert research on pickups, along with a bunch of information from the Wikipedia magnet entries and Magnet Kingdom, to give us an overview of magnets in general, as well an in-depth look at AlNiCo magnets for guitar pickups. More
Amp up your mojo with this strummable guitar shirt.
You touch the frets and strum with a magnetic pick and it plays through a little clip-on amp stack, which goes to 11 naturally.
Who says we can’t be both geek and guitarist? 🙂
They also have a drum shirt with the speaker/battery-pack embedded in the hem.
See the ridiculous band video here.