How much sustain is lost using more powerful magnets?

[esandes]

From a ceramic HB to an A2 HB, for example.

Does the type of bridge have more of an influence in sustain? I changed a jazzmaster bridge from TOM to mastery and the difference was very significant.

Just wondering if a pickup swap from ceramic to A2 will help increase sustain.

 

[beaubrummels]

I've not had humbucker pickup changes affect the sustain of any guitar I've owned.

 

[esandes]

So it must be my two point floating bridge sinking sustain.

 

[Mincer]

Yeah, I've never had any humbucker magnet affect the strings that way. Single coil slugs, yeah, if they are too close to the strings. An improperly cut nut can cause sustain issues, too.

 

[Chistopher]

It can effect apparent sustain due to volume and eq, but it cant really change the way the string vibrates

 

[Sam SG]

I've not had humbucker pickup changes affect the sustain of any guitar I've owned.

Same here.

 

[uOpt]

You can test that by comparing sustain at different pickup heights.

 

[marcello252]

^this

 

[uOpt]

Or remove the neck pickup altogether for a sustain test.

 

[Rex_Rocker]

I wonder if anyone has any gauss numbers regarding how much string pull there is a the top of a humbucker vs. a single coil? Or a triple ceramic hummie vs A2?

I'm usually not concerned with string pull from humbuckers, and I agree that maybe it's negligible, but it's certainly not 0. Especially on like a Black Winter, LOL.

 

[Chistopher]

I had a humbucker with a 1/2" neodynium bar magnet that did not alter the string pull in a noticeable way, so i doubt a 1/4" alnico could.

Now Strat polepieces definitely can

 

[freefrog]

I wonder if anyone has any gauss numbers regarding how much string pull there is a the top of a humbucker vs. a single coil? Or a triple ceramic hummie vs A2?

The longest rod magnets of a Strat pickup can easily reach 1000 to 1200 G right at the surface of the poles. A Gibson 500T goes up to 700G. A Duncan PG clocks at 260G. The weakest A2 loaded pickup in my own guitars rates @ 230G approximatively.

But flux strenght weakens very quickly with distance relatively to the strings. A 500T set 6mm under the strings measures 80G or something like that.

That said: the shape and width of the magnetic field is not indifferent here. Stratitis illustrates this idea.

I can't help to conclude by posting again a link that I've already shared more than once here:

Magnetic fields in pickups

Guitar building, tips, tricks and how to. Links to useful sites for the luthier and hobby guitar builder.

skguitar.com

 

[Rex_Rocker]

The longest rod magnets of a Strat pickup can easily reach 1000 to 1200 G right at the surface of the poles. A Gibson 500T goes up to 700G. A Duncan PG clocks at 260G. The weakest A2 loaded pickup in my own guitars rates @ 230G approximatively.

But flux strenght weakens very quickly with distance relatively to the strings. A 500T set 6mm under the strings measures 80G or something like that.

That said: the shape and width of the magnetic field is not indifferent here. Stratitis illustrates this idea.

That's interesting. So if I'm understandin what you're saying is even though the 500T is somewhat comparable to the string pull a single coil has, a single coil's string pull is more problematic because of the shape of the field it has? That's so interesting.

I wonder what a Slug's string pull is like. To my knowledge, that one has the magnets right against the strings, right?

 

[freefrog]

a single coil's string pull is more problematic because of the shape of the field it has? That's so interesting.

The magnetic field of a rod magnet is more powerful and more focused, hence the Stratitis effect. That said, the wide magnetic field of a triple ceramic HB is not necessarily innocent. I think to have data about that somewhere but TBH, I'm way too tired now to dig in my archives - and to be sure of my statement. :-/

 

[Chistopher]

I had a humbucker magnet that could lift a 25 LB plate and did not affect the string pull when in a guitar

 

[freefrog]

Still too tired to dig in my archives but Manfred Zollner's has shared in his PhD thesis a few interesting and accessible things. Excerpts:

In comparison to the string tension force (50 – 200 N) the magnetic forces are very small; the lateral string displacement caused by them is less than 0.1 mm. Nevertheless, the effect of the magnetic field must not be totally ignored, because its stiffness changes the frequency of the string. The nearer the string comes to the magnet, the more it is pulled. [...]
4.11.2 Field-Induced Deviations of the Tone Frequency
When a magnetic pickup approaches a string, three effects can be anticipated: The tone frequency decreases, chorus-like beat frequencies evolve and the amplitude changes. The frequencies, especially the fundamental, will decrease due to the negative field stiffness, which can be audible for large values. The detuning between the fretboard-normal and fretboard-parallel vibrations induces beat frequencies; the altered frequency relationship between the partial tones in the subsequent non-linear systems causes additional partial tones, which can further increase the chorus impression. True damping, i.e. removal of vibrating energy, occurs only to a negligible extent. [...]

Etc.

For those having not at disposal the lab gear used by Zollner, an instructive experiment would be to watch the harmonics captured by a bridge pickup while changing the height of a neck pickup.