Does the Construction of an Electric Guitar Affect Tone?

So this is an age-old question with people firmly planted in both camps. One group will adamantly adhere to the idea that guitars are magical machines capable of defying physics as we know it and that each is unique and different wherein only one can make the very special sounds it makes. The other group are staunch adherents to physics and they know that the only sound an electric guitar pickup can make is that which is generated by the change in electrical output as a result of the changing magnetic fields produced by ferrous strings moving in said magnetic field.

I'm here to say that both camps are slightly correct and slightly incorrect and it's all about construction (and physics).

Physics is generally right in this case in that if the pickups don't move and the strings don't move, there is no output. It's just that physics on paper is simplified and much cleaner than reality and, in reality, things are always moving.

As an experiment, you can plug in your guitar, max out the volume on your guitar and headphones on the cleanest setting you can find on your amp with no effects of any kind. Also, don't strum, we don't want to deafen anyone. If you just tap on the guitar with a knuckle while adjusting the volume you might convince yourself that you hear the rapping in the headphones. For some guitars, you might be right. Now, let's deaden the strings by placing a cloth below the strings and on top of the pickups, thick enough that there's a good bit of pressure on the strings and you're pretty confident the strings aren't going to move, and do the same rapping. Are you still convinced you can hear the sound? Again, you might actually be and here's why...

If your guitar was made of a material that did not vibrate at all when struck, you'd never hear a sound at all (except maybe the standard 60-cycle hum), but guitars are made of wood, carbon fiber, or other materials that do have the ability to vibrate, some more than others. Now, also consider how your pickups are mounted. On my strat, they are screwed in place and backed by pretty heavy springs. The wood is a solid Alder or similar wood. When I rap on this guitar with the strings muted, I hear nothing in the headphones. This is because there is (for all intents and purposes) no movement between the strings and the pickups, the vibration is too small to create any perceptible sound. However, on my Ibanez superstrat, I have an HSH configuration and the humbuckers are floating on much softer springs so that when I rap on the guitar body, the pickups do move some. Without the cloth in place, they move a lot more than you'd think and some sound from the vibrating wood is heard from the pickup vibrating, yet the single coil in the middle is just like the strat and doesn't move at all and once again produces no perceptible sound in the headphones.

What does this mean to someone who thinks that a guitar should have it's own character and not just sound like whatever pickups are put in it? Well, the more things vibrate, the more the construction will affect what the pickups pick up. Choose pickups that float more softly instead of being rigidly attached to the body. Choose a floating bridge as well since the springs will allow the strings to vibrate with the body. Also, I've noticed that the more solid the body, the less vibration and the less solid the more vibration there is. My strat has the most solid body of all my guitars and pretty much doesn't have any body vibration coming through the headphones, so it is the cleanest tone and really is only colored by its playability (and my skill, which isn't so great). However, my Jazzmaster has a lot of open cavities inside, with a solid tailpiece, I still get quite a bit of what I can only describe as a kind of reverb in the sound when rapping the guitar. This might explain why it was a popular choice for Surf Guitar. The pickups on the JM are supported by two medium sized springs and foam, so they don't get much vibration on their own, but it is still enough to color the sound a little.

One other popular guitar is the Rickenbacker 360. One might wonder what gives it such a characteristic sound. For once, it is a semi-hollow body, so less wood = more vibration in the strings and pickups. Plus, this guitar has a special set of pickups you won't find on other guitars. The combination is an open and jangly sound that you just don't get from other guitars. That doesn't mean you couldn't take those pickups and put them on something like an ES-335 and get something similar, maybe even better. Go ahead, give it a try :-)

Note that the more things do vibrate, the less sustain you will have. This is because the body frequencies are nowhere near those of the strings and will likely be out of phase causing the stings to deaden much quicker. The less vibration you have, the greater your sustain will be. Combined with humbucking pickups which have the lowest output and weakest magnetic field and sustain increases even further. To maximize sustain, use active electronics instead as they will increase your output without increasing magnetic field strength, thereby allowing the strings to vibrate longer.

Now, with all of this said, I have to stress that the vast majority of your sound is based on your electronics. Everything in your signal chain will alter the sound much more than the construction of the guitar. Quality electronics can make wonders of a cheap guitar. My JM is a Squier, solidly built, but had lousy pots (and the stock pickups weren't that great either), so I upgraded those for a much higher quality of sound. The rest of the guitar is awesome, BTW! My Ibanez super-strat is also cheap and could stand to have better pickups and electronics. When I do upgrade it, I'll make sure the pickups don't float because I want a pure sound out of whatever pickups I choose to put in it. I'll also probably block the Floyd-Rose bridge so that it doesn't move either. With that combination, I might get something closer to a Les Paul in sound quality, all on a cheap body with a neck that at least plays well.

I hope this helps some of you out there in choosing your next axe or modifying an existing one. Rock on!

Squire Vintage Modified Jazzmaster Pickguard and Electronics Upgrade

Ok, so this is not my typical technology discussion, but I love guitar and finally purchased a cheap enough one to be willing to modify it.

To start, we have in Tucson a company called Bookman's. They started initially with just used books that people could trade in for cash or store credit (you always got more with store credit). Eventually, they started taking other things such as board games, puzzles, knick-knacks, and musical instruments. Over the years, I've traded in a ton of old books and gaming consoles, such that I had about $200 in remaining credit to use. Since I've been buying all my books on Kindle lately (I like the convenience, okay), I couldn't think of anything else to put my credit to. That is, until a friend of mine mentioned that they had a VMJM available. I've been looking for a cheap way into the P90 sound, so I went down and looked at it. It played really well. I mean, surprisingly well for a cheap guitar. I was amazed by certain aspects of the build quality (though was disappointed in the warped pickguard). The guitar itself wasn't exactly treated nicely, and I know that I could have bought a brand new one for about $100 more, but this was $200 that I already had in credit, so I went with it.

Original guitar

Incidentally, I played terribly in the store. I don't play in public and was so nervous having to plug in and play with at least 50 people having to cringe at my mistakes. But, I heard enough to like the guitar and to know that once I got it home, it'd sound much better.

Fast forward a bit and I found that that while it did have a nice sound with volume and tone at full throttle, once you brought the volume down a notch or two, treble was just completely lost (I have since learned that this is normal and that there is a common modification that people employ called a Treble Bleed Circuit). I decided that since I didn't spend any real money on it, that I could stand to purchase some other pickups, replace the pots (I actually hated the stacked volume/tone pots), and felt it could use a bit better shielding.

On Amazon, I found a replacement pickguard in vintage cream for $6. One thing to note is that the pickguard on this guitar is different from most Jazzmasters. Notice how this guitar has the separate metal angled output jack. Most Jazzmasters have the output jack where the second pot is in the image above, and the pots are both moved up. Also, the pickup selector switch is traditionally on the lower bout and in the upper is the rhythm circuit. I also bought a roll of copper shielding tape and shielded the entire underside of the pickguard and most of the guitar cavities.

Copper shielding on new pickguard

Shielded cavities

I could have spent up to $350 on a loaded pickguard, but I decided it wasn't worth that, at least, not yet. I needed to try this on the cheap, so instead I purchased a set of completely new J Mascis wired electronics with pickups for $100 on Reverb.com. This way, I didn't have to spend a ton on more electronics, or lots of time on figuring out exactly what I'd do if I built this from scratch. Besides, I didn't want to go to the trouble of figuring out the whole rhythm switch circuit and I couldn't find a pickguard to match the existing (the original was warped and I hated that about it). So, the J. Mascis set was a good option. Besides, I really liked the idea of adjustable pole pieces for fine tuning. I did not bother to add the treble bleed circuit yet.

Example of warped pickguard, you can't quite see the bulge near the neck pickup, but it was also very annoying

After shielding the pickguard, I attached the electronics. I did have to solder a few parts as there were two grounds in the cavity; one to the inset to the treble side riser for the stop tailpiece and one just under the neck pickup. I also decided that I might as well wire up the existing output jack. Only one should be used at a time, but I wasn't sure which would be more sturdy, assuming the one in the pickguard would be less robust.

J. Mascis electronics attached to pickguard

The real trick was actually getting everything in place. The pickguard wasn't a perfect fit. I had to trim around the neck quite a bit to allow for greater flexibility to align the screw holes with the existing. In some cases I just had to create new holes. All that was mostly fine. The biggest challenge was with the pickup selector switch. It was a tad too big to fit in the corner designed for it so that once I had the pickguard in place, part of the switch housing came loose causing the switch not to work properly. It took me a few tries to figure that out, and not before I screwed everything down twice. Once I did figure it out, the next trick was determining how to fix it. Originally I looked for some glue, but then it dawned on me that I could use solder to hold it together and also to build up a false ledge on that one side of the switch so that inside the cavity it would be angled away from the wall. That little trick was enough to get it to fit without malfunctioning. I don't have any pictures of this fix, as I'm not proud of the gerry-rigging I had to do.

However, the selector switch still broke after a few months, so I ended up routing out the upper bout a bit.

Routing of upper bout on cutaway side to make room for selector switch

In addition to this, I found that the tone and volume wheels for the rhythm circuit were hard to turn, so I had to do a little routing on that end as well.

Routing of cavity for rhythm circuit volume and tone controls

Complete with new pickguard and electronics. I have to say, the vintage cream on both look better than the stark white of the original

Once everything was all together and actually working, then I had to tweak the pickup height for the low action I was trying to achieve. In the process, I learned what the rhythm circuit actually does. The original configuration had stacked tone and volume pots so that each pickup was controlled individually. I also didn't like that configuration much because as I switched I'd find that the volume would change if not perfectly aligned. It also made setup a little more challenging. I'm used to a strat configuration where the volume was a set value and the the tone knobs were separate. The rhythm circuit is similar, but different. When not using the rhythm circuit, you have one volume and tone that controls both pickups equally, depending on the pickup selector position. When the rhythm switch is engaged, then only the neck pickup is active and it uses the separate volume and tone wheels on the high side of the upper bout. At first, I was confused by why one would want this. Then it dawned on me that in the heyday of the Jazzmaster, there was no "lead" guitarist, it was just "the" guitarist. The idea was to provide an easy way to preset a rhythm sound to switch to. With that in mind, I'm not sure how much I'll actually use the rhythm circuit, but since I understand it a bit more, I might actually try to find uses for it.

There are a few ways I might still modify the guitar. Obviously, I don't need two output jacks, so I could put in another control where the output jack is in the pickguard. That control could be a pan knob, or I could put in a push/pull pot to engage a treble bleed circuit, using the pot resistor to allow for fine tuning of the circuit (normally you put in a physical static resistor). I'd also like to add a switch to reverse the polarity of one pickup to allow for some subtle humbucking. Of course, I'll have to read up on that as I'm sure it isn't so simple.

In the end, how do I feel about it? Well, as I said originally, I liked how the guitar originally played and sounded. The new electronics sound better, especially since I had greater control of the sound with the adjustable pole pieces. I find this guitar to be rather unique. It is solidly made. The woods aren't the greatest, but one thing you'll find to be rare on these guitars is a maple fretboard, of which I really like the feel. Combined with the jumbo frets, which are phenomenally dressed for a cheap guitar, it's quite comfortable to play. The J. Mascis pickups are actually cleaner than the originals. I was kind of hoping for something a little darker, but I'm actually really digging the clean jazz tones I can eek out of this.

I like the adjustable pole pieces a lot. I know I've mentioned them several times before and for good reason. On traditional Jazzmasters, the volume of each string is naturally higher at the low and high ends of the spectrum. This is because you have strings heights relevant to each pole piece that are different. But with the adjustable pole pieces, you can keep the string heights relatively the same. In this way, you can capitalize on the natural resonance of the Jazzmaster and create a more well-rounded tone by maximizing the mid-range. If you've ever wondered how electric guitars can sound different even if they have the same electronics, consider recording them unplugged. I did this with my strat and the JM and found that the added heft of the JM as well as more open cavities provided both a resonance and sustain I couldn't get out of my strat. The pole pieces did not require much if any adjustment at the neck, but at the bridge it really made the difference. I'm not one who likes that tele or strat bridge pickup twang, it's too sharp and almost unpleasant to me. So, making the adjustments on the JM at the bridge was a tremendous improvement.

All in all, I'm pretty happy with this guitar and the mods. It's wonderful for both surf guitar and jazz. I also enjoyed playing some STP and Nirvana with it (while similar to a jaguar and sufficient at producing the tone, it still isn't a perfect match for Curt's sound). I also very much prefer it in the neck position to position 4 on the strat for Yellow Ledbetter, it's just more full sounding than the strat to me. I can also get a nice warmth and jangly tone from the neck pickup which when combined with a fair amount of spring reverb and slight gain on a Fender twin, produces the perfect surf rock sound of the 60's.