Re: Now Call me "The Titanium Man"
Found this explanation from a pretty brilliant engineer in reference to the Strat block only. Sounds about right to me;
QUOTE;
Personally, I think most of the perceived change in tonal character achieved through changing the material the "sustain" block is made of is due largely to the power of suggestion. Spend $150 on a titanium block, and you're going to do your best to convince yourself that it's better somehow. Understand, I'm not saying that it doesn't make a difference, only that its influence is probably overrated.
Having said that, there are some arguments that make sense, depending on the effect you're trying to achieve. Because different metals have different hardnesses and densities (among other characteristics), they respond differently to stress.
Metal Hardness Density
Titanium 334 4.43
Steel 130 7.75
Brass 60 8.5
Aluminum 160 2.7
Zinc 45 7.1
Disregarding the static tension a string imposes on its mounting points, the stress on those points is mainly vibration. The vibration of the string(s) is what we want to hear, so what effect is the mounting point's properties going to have on that?
Since the object of the exercise is to hear the strings vibrate, anything that absorbs those vibrations could be thought to be detrimental. So, you would want your mounting point to have a lot of mass so that inertia will tend to hold that point still. Going by that, the block materials that would make sense for increased sustain would fall in this order, from longest to shortest
Brass
Steel
Zinc
Titanium
Aluminum
For increased frequency response, you would want something harder. The block materials that would make sense for that would fall in this order, from highest to lowest
Titanium
Aluminum
Steel
Brass
Zinc
All things considered, steel is probably the best material overall for general purposes. Titanium will be brighter, but you'll lose sustain. Brass would have better sustain, but you'd lose frequency response. Aluminum and zinc don't appear to be particularly good at anything for our purposes, although from a manufacturing standpoint they're far and away the easiest/cheapest to produce.
It's telling that regardless of the numbers, aluminum and zinc are the most common materials used. Why? Cost is certainly a factor. Aluminum and zinc are fairly inexpensive just as raw materials, but so is steel. However, both the former are easily die cast, which eliminates a LOT of machining. That saves time and tools, which are both expensive.
Keeping in mind that all of the materials mentioned are going to be mounted to wood, which is considerably softer and less dense than metal, and that all the considerations have to do with vibration absorption, I think the reality is that when it comes to sustain blocks the difference the material makes is not prominent enough to justify anything exotic.
..... that titanium is largely a waste of money on a guitar. It's not a bad metal at all, and is actually better than what the OEMs use (die cast zinc), but it's not as good as milled steel or brass. You actually want some mass to the bridge assembly, so it doesn't absorb vibrations. Titanium will give you less of that than even the zinc. You also want hardness, and titanium is harder than zinc, but softer than brass or steel. So, if you want better sustain and frequency response (articulation), you want either a brass or steel sustaim block. Brass might a slight edge in sustain, steel might have a slight edge in frequency response, but they'd be comparable.
Then, you want a hardened baseplate so it doesn't wear at the pivot points, and milled saddles rather than those flimsy roll-formed pieces of crap Fender uses. "But they have tone!!!" No, they don't. They eat tone, and what's left is what people think is good.
In utopia, when you start a string vibrating, it never stops and it generates harmonics all the way up past the limits of human hearing. In reality, a dozen or so things are preventing that from happening. Your mission, should you decide to accept it, is to minimize the influence of all those things that are trying to eat harmonics and make the string stop vibrating. So, fewer joints, hard anchors and lotsa mass. That includes the neck joint - that's like a hinge on the whole assembly. You want that to be nice and tight. That's why I've been putting threaded inserts and machine screws in for years. It's also (one of the reasons) why I don't use Floyds. Too many joints.
You can always filter out frequencies you don't want with either the guitar's tone controls, the sfx's, the amp's, the PA or recording EQ, etc. You can't add them in if they're missing because the guitar itself is eating them at birth.
For increased frequency response, you would want something harder. The block materials that would make sense for that would fall in this order, from highest to lowest
Titanium
Aluminum
Steel
Brass
Zinc
then...
..... that titanium is largely a waste of money on a guitar. It's not a bad metal at all, and is actually better than what the OEMs use (die cast zinc), but it's not as good as milled steel or brass. You actually want some mass to the bridge assembly, so it doesn't absorb vibrations. Titanium will give you less of that than even the zinc. You also want hardness, and titanium is harder than zinc, but softer than brass or steel
[When I wrote that first bit I confused Titanium's strength-to-weight ratio with hardness. It's actually somewhat flexible, which among other things is what makes it desirable for air/space craft. You can make a fairly strong part that weighs less and won't crack or work harden as easily under stress, which is something neither steel nor aluminum is good at. But, being somewhat springy (relatively speaking) means it'll absorb vibration more than steel or aluminum, which are more brittle. It'll deform and bounce back, which would have a deadening effect.
Keep in mind we're talking relative numbers here. Titanium is far from "springy", but compared to untreated steel or aluminum it is. Still, small things matter when we're talking about the small vibrations you see in a musical instrument.]