Height of the bridge and sustain

[Guitarman555]

I spent tons of time with setting up pickups, bridge, experimenting etc on my 64 jag. Sounds great now, thick tone with tons of mids, no buzzing, great stratish tone thanks to 64 staggered pickup.

What I am still thinking about is sustain -sustain is ok but could be better in comparison with the same period jazzmasters and 62 jag. Is it worth to get bridge higher to get bigger angle of strings direction to tail and get bigger sustain? I would have to increase angle of neck (stewmac shim with non sufficien angle is installed) with additional piece of thin wood/any material shim to get the bridge higher? Not sure if the higher bridge would really impact sustain recognisably.
I measured height of the high strin E2 saddle - distance from the wood to the top of the saddle where string touches the saddle. It is about 3 or 4 mm lower in comparison with other guitars.

Not sure if it is really worth to setup everything again. Maybe just business card on top of the stewmac shim in the rear of neckpocket would help?

[Guitarman555]

I have just uninstalled 5degree stewmac shim and discovered a dent inside the pocket. There is also repaired neck pocket wall by plastic(the blueish colour at the right side of pocket). The holes are too big (only in the pocket), not neck itself. The screws just flow through the pocket. But they fix well in the neck part of connection so i let it be. I installed back the stewmac and a thick sandpaper and it allowed me get bridge much higher. Sustain did increase. Thinking if to put tiny slices of wood into the 4 holes in neckpocket. Also thinking if to fill the dent inside pocket or let it be.

[andy_tchp]

The holes are too big (only in the pocket), not neck itself. The screws just flow through the pocket.

They are supposed to, the holes in the body are not 'too big'. You do not want the screws 'biting' into both surfaces being fastened together, just the neck itself.

[superficial]

Indeed. It’s called a ‘lag screw’ and is how you get the neck to sit tightly in the pocket.

[DrippyReverbTremolo]

I doubt that a higher bridge will have more sustain. But I'm open to facts and hypotheticals.

[46346]

sometimes sustain can be lost if the pickup is too close to the string, creating a magnetic pull on the string.
when that is the case, raising the bridge can help sustain. but more commonly, i would lower the pickup height to see
if sustain improves.

unfortunately, changing the pickup height from the string will also affect the tone and volume.

and just like you noticed, raising the bridge to increase the break-angle of strings to the trem plate will help, too.

the Jaguar is generally not a high-sustain guitar. but i like to have plenty of sustain, and have used
a Staytrem or Mastery bridge to help achieve that. but i've also heard stock set-ups sing out well.

happy tweaking!

[Highnumbers]

I have just uninstalled 5degree stewmac shim and discovered a dent inside the pocket. There is also repaired neck pocket wall by plastic(the blueish colour at the right side of pocket). The holes are too big (only in the pocket), not neck itself. The screws just flow through the pocket. But they fix well in the neck part of connection so i let it be. I installed back the stewmac and a thick sandpaper and it allowed me get bridge much higher. Sustain did increase. Thinking if to put tiny slices of wood into the 4 holes in neckpocket. Also thinking if to fill the dent inside pocket or let it be.

Personally, I would skip any mickey mouse approach like putting slivers of wood into the holes. That's a temporary fix at best. The proper repair (at least for the front two holes) is filling them completely with a solid wood dowel, then re-drilling the hole in the correct size.

As Andy points out, you don't want the screws biting into the body wood at all, they should pass through the body easily. But you also don't want the body mounting holes oversize, allowing the neck to move around while fastening it down, or worse...while playing.

[nethanpaul]

Raising your bridge can definitely help with sustain on your 64 Jag! A higher bridge increases the string break angle over the saddle, transferring more vibration into the body. The small difference you measured (3-4mm) could make a noticeable improvement.
Adding a business card on top of your current shim is a cheap way to experiment. However, a business card might be too thick and alter the playing experience. Consider a dedicated neck shim with a precise thickness for optimal results. Remember, a proper setup is key – so even if you raise the bridge, you might need to adjust other aspects like the action and intonation.

[GilmourD]

I doubt that a higher bridge will have more sustain. But I'm open to facts and hypotheticals.

It's not so much that the bridge is higher but rather than there's more downward pressure on the bridge.

If you look at the bridge from the side you'll see that the strings leave the bridge at an angle when heading towards the trem/tailpiece. If it's low, that angle is fairly small and you'll also notice that it's easier to move the string laterally. With a higher bridge you can think of it like how when you bend a string it becomes harder and presses more against your fingers the more you bend. The strings no longer lift easily or move laterally and have more "bite" into the saddles. This also basically pushes the bridge down harder into the thimbles.

So, this not only aids in tuning stability (with a rocking bridge you DO NOT want the strings sliding on the saddles but rather holding on for dear life so that way when the bridge returns to the straight-up position they're still in the same place. But also, with the bridge more firmly pressed down into the thimbles you give the bridge that doesn't absorb the vibrations of the strings but supports the strings as they vibrate, and thus help the strings vibrate longer and stronger.

[timtam]

Raising your bridge can definitely help with sustain on your 64 Jag! A higher bridge increases the string break angle over the saddle, transferring more vibration into the body.

If more string vibrations were transferred into the body, that would mean loss of string vibrations from the strings - so not seen by the pickups. That is, the exact opposite of sustain. That's the Conservation of Energy Law as it applies to guitars.

That this specious notion of "transfer of vibrations to the body" as a "good" thing is not uncommon amongst guitarists is seemingly a result of a science-challenged 'echo chamber' of famous players, guitar journalists*, and guitar manufacturers - promulgating notions about how guitars work that often contravene the laws of physics. You don't need to fully understand guitar physics to play, write about, or build great guitars ... but you do need that understanding to talk as if you do and actually know what you're talking about. Unfortunately people feel their solid body guitars vibrating and jump to completely wrong conclusions about what that small vibration magnitude actually means. It's lucky that they're wrong about body vibrations, because their guitars would have very poor sustain if they were right.

*Zollner quotes an assertion from the echo chamber about solid-body guitars - in this case a German guitar journalist - in the early part of section 7.5 in his book ...
"The largest portion of the string vibration should be transmitted to the body. Indeed, if the latter is supplied with uninhibited vibration energy, a maximum in tone and sustain develops.[Gitarre&Bass 12/05]"
Zollner, M. (2014). Neck and body of the guitar. Ch 7 in: Physics of the Electric Guitar. https://www.gitec-forum-eng.de/the-book/

That journalist is talking complete and utter physics nonsense.

I've held off on saying anything in this thread before now because the precise physics of how bridge height/break angle affects string vibrations is complex - it evades easy answers. If you want to see that, read ch7 of the Zollner's above-cited "Physics of the Electric Guitar" (free to download). Mainly section 7.5 Reflection and Absorption at Bridge and Nut.

We do know that sustain is maintained by anything that avoids the loss of string vibrations going to vibrate other parts of the guitar - the bridge, the neck, the body, the trem, etc. We also know that those losses are small in solid-body electric guitars. Almost all string vibrations are reflected back up the string when they reach the bridge. All direct measurements of real guitars over the last several decades show that - bridge admittance, neck admittance, direct string vibration measurements, direct sustain measurements, direct neck and body vibration measurements. etc. That is, measurements of different physical phenomena - on different guitars, by different people, in different labs - that all point to the same conclusions. That's why sustain is generally good in most solid-body electric guitars (and some of the reasons why it can vary have more to do with pickups and signal chains). See in particular the independent work of Fleischer, Zollner, and Pate.

The sustain-enhancing effect that one might have expected to see would be that increased bridge height/break angle increases the reflection of string vibrations back to the string. That is, presenting greater mechanical impedance to string vibrations, causing more of them to be reflected back up the string, and thus maintaining sustain. As opposed to allowing some vibrations to pass over the bridge into the 'residual' string length behind the bridge, and some to pass into the bridge.

But it doesn't quite pan out that simply when direct measurements are done (see Zollner section 7.5). An increase in break angle actually reduces the proportion of the string's initial transverse wave reflection; but there is also an increasing transformation from transversal to longitudinal energy with break angle, that considerably complicates the picture. As I said, no easy answers.

As I indicated earlier, reflection back up the string is still the predominant fate of almost all string vibrations reaching the bridge. Otherwise sustain would be very poor. So we are not talking about a significant detriment to sustain of adjusting a bridge in the 'wrong' way or an enhancement with the 'right' way. Whatever those adjustments might be.

[andy_tchp]

Great post ^

Sadly you’ve replied to an AI bot autogenerating “discussion”, including a clumsy reference to Jaguar cars in reply to a thread about a vintage jag

[windmill]

It's always good that Timtam comes along and gives the science behind the guitar.

One day I hope to remember all those things he talks about.

☺