I was nosing around the Les Paul Forum today and came upon an older thread that had to do with pickup spacing. That’s a pretty irrelevant subject with 335’s and their brethren because Gibson never messed with the pickup placement on these guitars. Still it’s interesting and you can read it here. I think you can access it even if you aren’t a member. But a few of the posts discuss wolf notes-notes that are louder and more resonant and dead spots which is, essentially, the opposite-notes that are less loud and resonant. Fully hollow instruments have all kinds of vibrations going on and the relationship between these vibrations is key to how the instrument sounds. If the top is vibrating one way and the back is vibrating another, then they can cancel each other out. It’s a little like out phase pickups-certain frequencies are enhanced while others are diminished. There’s tons of math and physics involved in the finer points but the over all gist is that the front and the back should be vibrating more or less together to sound balanced. Violins and cellos have a post inserted between the top and the back (called, cleverly, a sound post) and it transmits some of the vibration from the top to the back helping them to vibrate more in sync.
I remember as a 4th grader taking violin lessons and the “A” was really loud and sounded almost like it was feeding back. You could feel the instrument come alive when you played an “A”. Sort of cool but not a good thing unless the only note you’re going to play is “A” (which probably would have been an improvement for me). My teacher looked inside the cheap rental violin and announced that it had no sound post. He rummaged around in a little box of parts and came up with a small wooden dowel-a sound post. He had this strange little bent metal tool and used it to wedge the post between the top and the back near the bridge. Problem solved-at least for the purposes of a 4th grader. An amplified instrument will make discrepancies like this become glaring. In general, guitars don’t have sound posts. Carved spruce top arch tops like L5’s, Super 400’s and a few others, can be “tap tuned” – the builder taps the top and carves away wood until the tone of the tap is consistent throughout-and this goes a long way in eliminating wolf tones and dead spots. Whether a sound post would improve it further is up for debate. I don’t get to play a lot of fancy arch tops. Feel free to send me one if you’re not using it.
This brings us to laminate tops like you find on ES models. The tops on all arched ES’s are stamped from a flat sheet of plywood. No carving (or tap tuning) involved. And if the top and the back don’t vibrate at the same rate, tough crap. You get wolf notes and dead spots. That explains the high level of inconsistency I’ve experienced from ES-330’s and ES-175’s. Some are just great but some just suck. In a worst case, half the notes seem dead, a quarter of them normal and the other quarter howling at the moon. Especially when amplified. Recently I’ve had a lot of ES-330’s and mostly, I’ve been lucky. The next time I get one that isn’t sounding right, I’m going to insert a sound post and see what happens. Stay tuned.
Finally, one of the best things about ES-335’s-particularly early ones-is their great consistency of tone. I rarely get a bad one and I find 90% fall into the classification of excellent tone. There are perhaps 5% that are exceptional-those magical ones that I hate to sell. Another 5% might fall into the “ho-hum” (that’s a technical term) classification-these are guitars that just don’t quite have that great 335 tone I’ve come to expect. There are a lot of ways to make a ho-hum sounding 335 better and I’ll write a post about that later. but, to the point, one of the biggest reasons that 335’s sound so consistently great is that big ol’ block of maple and spruce down the middle. It keeps the top from interfering with the back. It is, more or less, a giant sound post.