Author Topic: Sustain block? (Read 659 times)

richbass939 · « **on:** May 29, 2005, 06:05:14 PM »

Can someone explain the theory behind the sustain block? What are its dimensions? Exactly where is it? Is it brass? Are there any pictures of one being installed? Pictures of the hole it goes in? How is it installed? I would appreciate the info.
Rich

David Houck · « **Reply #1 on:** May 29, 2005, 06:36:41 PM »

The sustain block sits underneath the bridge; and yes it is brass. The picture of the bass in progress on this page shows the routing for the sustain block along with the pickups. The routing in the picture shows the size of the block. On a bass with no sustain block, the bridge screws directly into the wood; thus there would be no routing as in the picture. The block is screwed into the body with a single screw; the bridge is then screwed into the sustain block with two screws. As far as the theory, it's been discussed before but I can't remember technical stuff. In fact, someone in the group did some experiments with sustain blocks of different materials and reported the results.

David Houck · « **Reply #2 on:** May 29, 2005, 07:10:25 PM »

Found it! I looked at the FAQ section and found this thread that answers your question about the theory behind the sustain block. Oh, and it was Bob Novy who did the experiments with different block materials. Here's another thread on the subject.

bob · « **Reply #3 on:** May 30, 2005, 12:28:57 AM »

... which reminds me, I haven't yet gotten around to posting my results, though it would probably be more than most of you want to read.

The simplistic answer is that the extra mass of the brass helps to keep the energy in the strings, rather than bleeding out into the body, so you get more sustain.

While I believe that's generally true, I'm convinced I hear differences using blocks that weigh the same but are made of different materials. This is perhaps more a difference in tone across the strings, than overall sustain (which was slightly less interesting to me personally).

But then again, using the same material for two blocks, and inserting some weights in one of them, I preferred the heavier one for more even response, which favors the argument that (for me, at least) heavier is better.

I've settled on a block I made that contains a high proportion of tungsten, and weighs 450 grams, versus the 300 gram brass block I started with (I was going for a full pound, missed by just a few grams).

I'm not sure I should admit this, but I actually tried 11 different blocks. In hindsight, brass is pretty darn good...

I wasn't able to compare the basic difference between having a sustain block, or just screwing the bridge into the body - that's a somewhat more difficult experiment. But I think it's safe to say that you will definitely get more sustain, and more consistent tone (balance of harmonics) across the strings. I also believe it will somewhat reduce the influence of the body woods, though these will still certainly make a difference.

David Houck · « **Reply #4 on:** May 30, 2005, 06:02:23 AM »

Thanks Bob!

richbass939 · « **Reply #5 on:** June 01, 2005, 04:01:54 PM »

Well, it?s taken a little while but I finally read and digested all the posts referenced above.
I previously thought that all Alembics had sustain blocks. I thought that my Epics had blocks that were buried in the body and the bridge-height adjustment screws were screwed into them. I never noticed on pictures of the other Alembics that there appears to be a block that is flush with the top.
So, if I finally have this right, neck-thru basses have them and set-necks do not. Block material does, as we would expect, have a significant effect on the sound.
Now back to my specific application. I am rebuilding a bass I made a dozen years ago. It is a fretless and will have flatwound strings on it. I am using maple for the body core to brighten it up a little. It has a maple neck. It is currently a bolt-on but I am going to make it a set-neck this time around.
I wanted to consider the sustain block early in the planning. It seems now that I might not even want to install a sustain block as none of the Alembic set-necks have them. I love to experiment but I trust the elves to know what helps and what doesn?t. I don?t want to spend extra time and money if there will not be any real effect. Besides, I suppose you wouldn?t start out with a fretless if killer sustain is your goal.
A lot of the info in these posts can be put to good use in selecting a material for the bridge. It seems that some of the same theory applies.
Thanks to you all.
Rich

sfnic · « **Reply #6 on:** June 01, 2005, 04:25:50 PM »

(Personally, I think a set-neck fretless with flatwounds is a _perfect_ candidate for a sustain block. It should brighten the string somewhat, and seriously increase the mwah factor.)

jagerphan84 · « **Reply #7 on:** June 01, 2005, 04:40:41 PM »

I'd have to agree with your speculation there, Nic... [gratuitous link to my custom]

-Adam

[note: strings are now TI jazz flats.]

(Message edited by jagerphan84 on June 01, 2005)

bob · « **Reply #8 on:** June 01, 2005, 05:57:21 PM »

It looks like you're right, that the block is standard on a neck-thru and not on a set-neck. However, I wouldn't read that as saying they think it would be a bad thing on a set-neck.

Keep in mind this is a very large chunk of brass. Even on a narrow 4 string it will still be about half a pound, and brass isn't cheap. Oddly, you can't figure it out from the custom quote generator, but (don't quote me on this) I seem to recall that as an option it would be on the order of $250-300, so it would increase the price of the set-necks quite a bit.

My guess is that is more likely the reason, as opposed to it doesn't work, and I'd also be in favor of adding one.

David Houck · « **Reply #9 on:** June 01, 2005, 05:59:59 PM »

neck-thru basses have them and set-necks do not

As far as new basses, I don't know the answer. But I don't think it necessarily holds true on older basses. Neither my 84 Spoiler nor my 90 Essence came with bridge blocks, though the Essence is currently in Santa Rosa and a bridge block is one of the mods it's getting.

smokin_dave · « **Reply #10 on:** June 01, 2005, 06:55:10 PM »

Interesting.I was just going over the catalog that was supplied to me when I received my Rogue in 2003 and every bass discribed in there states that they have a sustain block.I think all Alembics,set neck or not,have a sustain block and alway's have.I'm not about to rip apart the top off my 94' Epic to find out but I'm sure it's there.Maybe Val or modder Dave can shed some light on the history of the block and when they were incorporated in Alembic basses.

David Houck · « **Reply #11 on:** June 01, 2005, 09:08:19 PM »

Dave;

I have no idea about the history, but looking at the Showcase section, it does appear that very early basses did have them.

But I don't believe your supposition, that all Alembics have always had sustain blocks, is correct. After all, the folks in Santa Rosa only just recently routed my '90 Essence for a block. And if you don't see that your bridge is screwed into a piece of brass, then it's probably not there. I do think that there have been exceptions where someone custom ordered a bass with a hidden sustain block; but I think the general rule is that if you can't see it, it's not there. However, I can understand why you would think it is there; even the basses without blocks sustain well. And I imagine the brass bridges are a big part of why they do. My Essence had very good sustain without the block. I'm just looking to add a little more!

trekster · « **Reply #12 on:** June 02, 2005, 04:41:29 AM »

Hmmm..this brings up an interesting question in my mind. I have a book on Guitar Electronics and Modifications, where the author does the sustain block under the bridge. However, instead of a one-piece slug 'o brass, he used several plates stacked upon each other (I beleive his thinking was that he could experiment with different weights/sizes/materials).

It makes sense from the experimentation POV, but I wonder if doing it this way would take away from the sustain qualities vs a solid block? I'm supposing that, as long as the plates are perfectly flat and he has them compressed together with a single or couple screws, it would act as one piece.

Comments?

--T

(Message edited by trekster on June 02, 2005)

kmh364 · « **Reply #13 on:** June 02, 2005, 06:54:00 AM »

Sorry, repeat post.

(Message edited by kmh364 on June 02, 2005)

kmh364 · « **Reply #14 on:** June 02, 2005, 06:54:21 AM »

I don't know about all set necks, but my Orion definitely doesn't have one. The only set neck I actually recall seeing with one is this one (click below), but it was a custom option. Had I known beforehand that I could have gotten the block and the wide neck lams, I would have done so. I don't know about the effect on sound, sustain, etc., but I would have got them just cause they were cool and not everyone else has them, LOL!

http://club.alembic.com/Images/631/932.html?1031117669