Shims & Sustain ?

[tommyindelaware]

seems to me.......that if you insert a shim in one end of the neck pocket to change the angle of the fingerboard......you would be creating a gap between the flat bottom of the neck pocket & the flat back side of the neck.....having a negative effect on the sustain quality of the instrument.
the neck and the body have to interact w/ each other as one. the better the neck and body are coupled together...the better the instrument will sustain.
if your action is too high due to the neck pocket being too deep...install a spacer that is the same size as the bottom of the neck pocket that will allow the bottom of the neck pocket & the flat back of the neck to remain gapless & retaing the proper plane of the fretboard......while raising the fretboard to the needed plane.....or height........and allowing the body and neck to be coupled together as effeciently as possible w/ reguard to both vibrating as one......and the most efficient use of string energy. isn't this what the 5 & 6 bolt EB necks are all about ?
i would make the spacer from maple...... like the neck....

 

[hbucker]

I can't disagree with you in theory. But here are some things to think about:

1. Properly shimmed, I doubt you could tell a sustain difference between the shimmed guitar and the guitar without a shim. In a perfect scenario you wouldn't need shims. In fact, I'd be interested to hear why shims are a part of the Axis/EVH design in the first place. That being said, for practical purposes, a slight shim doesn't change sustain noticeably IMO.

2. The space you're talking about with a narrow shim (Like the ones used in the EVH/Axis) is VERY slight. So slight you'd have a hard time slipping a piece of paper into the gap or even seeing a gap in the first place. And with the proper shim, the neck is still contacting the body securely. Even if it isn't in quite the same way.

3. IMO you should use a hard, resonant material for shimming. If you can get it narrow enough, wood would be a good thought. Making it as narrow as you need is the trick. After a certain thinness, it will just start falling apart. We're talking as thin as the thinnest guitar picks or even thinner.

4. Part of using a very narrow shim at the base of the neck pocket is to angle the neck slightly so that you don't need a lot of shimming material and thus the original guitar tone and sustain are saved. If you put a flat shim in the neck pocket and raised the neck uniformly, you would need to use A LOT more shimming material. I'm not so sure this would be better for sustain and resonance than to use a very thin shim and letting the neck angle to work for you.

IMO A shim like the one you are talking about would no doubt become more of a characteristic in the guitar's over all tone and feel. Not something you really want from a shim.

Just my thoughts.

 

[tommyindelaware]

we will have to agree to disagree......

a gap is a gap... 1/96th of an inch......or 1/8th inch..w/ the same effect .....interupting string energy between the neck and the body...
a gap filled w/air will not transfer vibrations as well as a nice perfectly cut piece of neck matching hardwood compressed between the 2 flat surfaces.
i have never liked floyd equipped guitars as much as hardtails......i really think floyd guitars typically.. (even unshimmed).... lack a slight broad midrange punch. and.... granted......this is also a matter of personal midrange preference.

 

[bluebullet]

i hear what you are saying tommy but i can tell you sustain has never been a problem on my axis and i dont play at high volume levels either. i am curious as to why ebmm needs them though with the cnc equipment they use you would think that the neck pockets could be cut at the correct angle. if warmoth can do it surely music man can. but im sure there is a good reason though.

 

[SteveB]

I would guess that shims are needed at times because the necks are unfinished, and being made of wood, tend to react to humidity. Wood is not always consistent.. go to Home Depot and try to pick out a dozen straight 2 by 4's. You'll have to pick through a whole pallet. Theoretically, each one was cut using precise, highly automated machinery, yet you'll find them bowing in many directions.

I think we're talking about tighter tolerances, too. EBMM is known for great feeling and great playing necks. If it takes the odd shim to get an instrument tweaked to maximum playability, so be it.

 

[hbucker]

Like I said in my other post, I agree in theory that a shim would-should-could cut sustain and tone. In it's purest analysis, I think it probably does. But sometimes I think we apply audiophile tolerances to guitar tone that can't withstand that scrutiny. Ultimately the tone coming from out amps is generated by so many variables that are imperfect at best. It’s not like measuring harmonic distortion or exact frequency output on a curve.

In the end it’s the performance of the guitar and rig that matters. If you can tell a difference, I’m not going to tell you otherwise. But I don’t believe most people could tell the difference. I could segue into tone woods here since it’s a similar discussion but I won’t...

My EVH sustains excellently. AND I can tell you I like the feel better with the action lower on the upper frets. Without the shim perhaps my sustain would be a little better (hard to believe) but the guitar wouldn’t feel nearly as good due to high action on the upper frets. That’s a feel I do notice.

I personally believe the shim is designed into the Axis. Perhaps somebody with EBMM can tell me I’m wrong. But I’ve got two Wolfgangs, neither has a shim and the action is perfect. EBMM has the ability to make the neck routes exactly the way they want and could do it without needing shims if they wanted to.

 

[Jimi D]

It's been my experience - however personal - that a good shim job will more often than not improve the sustain and tone of a bolt-on instrument. On a non-Floyd guitar, I suspect this is due to increasing the break angle of the strings over the bridge, increasing contact between the saddles and the string and improving the transfer of vibration to the body. Old Tele hounds are famous for shimming their necks to improve tone and sustain. I think ultimately, it's a matter of personal preference, but blanket statements like "shims hurt tone" are demonstrably inaccurate, ime...

 

[tommyindelaware]

It's been my experience - however personal - that a good shim job will more often than not improve the sustain and tone of a bolt-on instrument. On a non-Floyd guitar, I suspect this is do to increasing the break angle of the strings over the bridge, increasing contact between the saddles and the string and improving the transfer of vibration to the body. Old Tele hounds are famous for shimming their necks to improve tone and sustain. I think ultimately, it's a matter of personal preference, but blanket statements like "shims hurt tone" are demonstrably inaccurate, ime...

i didn't make a blanket statement that "shims hurt tone" ....i was simply trying to say that some shims may work better than others.....based on what i have experienced.....there are good shim jobs .......and bad shim jobs....
i did use the word negative.....but try and think of it in the context that i was using it.......kinda like positive and negative on a battery.....or my amp distorts...
i'm not dissing floyd users or something......after all.......if satch, via, dan huff and buzz feiten use them all the time......it's obvious they get the job done very nicely....
starting to feel a little politically incorrect here

 

[Jimi D]

starting to feel a little politically incorrect here

Hey Tommy, I'm not trying to bring anybody down - sure, a bad setup, shimmed or not, can mess up a guitar's sustain... I was just sharing my experience, which seems to be contrary to the popular, "logical" assumption that a shim must be bad for your tone...

 

[tommyindelaware]

i think jon should make us come over to the amp room......and let us play some hardtails......put a few shims in this & that........this way & that way......
i got dibs on the y2d floyd & hardtail....

seriously though........i have seen some really nice shim work.
this one guy i use to work for (dana of the scoop guitar fame).....did these thin..small wedge shaped spacers that fit in the whole neck pocket.....got me messin w/ this stuff a while ago......the differences are barely noticeable (if at all) under typical conditions....but very noticable under others.

fun stuff to play & tinker with........

 

[hbucker]

Jimi,

Good point about shims possibly improving tone. While I was arguing that shims don't have to hurt tone, I didn't take it as far as you did.

The general school of thought is that more contact between parts: neck, pickups bolted to the body, fixed bridge, etc. the more resonance, tone and sustain there will be.

Yet it seems that if you get all kinds of vibrations occuring in the guitar while it's playing, some of those vibrations will cancel each other out. Thus making them irrelevant.

Changing the resonance of a guitar in some way whether it's a shim, adjusting the bridge or whatever, can change the resonance and actually enhance key frequencies in the guitar even though there may technically be less of them bouncing around at any given time.

It would vary from guitar to guitar, even between "identical" guitars. I wasn't aware that Tele players actually shimmed exclussively to get a certain tone.

Is there anything you don't know?

All hail Jimi

thanks