Could adding a J pickup to a P cause new deadspot???

[remo]

I'm very close to adding a J pickup to my P bass. Currently there are no real deadspots on this bass, even on the G string (this is why I purchased it!!!). I am wondering if routing the body and adding a J pickup could somehow upset the resonance of the body and cause a new deadspot to appear on the neck?

I realise the possibility of this happening is remote, and the J pickup going into the route will probably makeup for any wood mass lost during the route...

but I thought I would put it out there and see if andone has had any experience with routing causing new deadspots..

[joelb79]

Dead spots... To my understanding, there is no way anything done to the body as far as routing a new pickup could cause dead spots.

[remo]

how many grams of wood would be removed in a normal J pickup route?

[Stox]

Deadspots = voodoo in my experience. Density of the wood in the neck or presence of graphite bars seem to be the main culprits.

[fenderx55]

They could also just develop. When I bought my MIA J it was deadspot free, then after about 6 months I guess the wood settled in and it has one.

[Webtroll]

Originally Posted by Stox

Deadspots = voodoo in my experience. Density of the wood in the neck or presence of graphite bars seem to be the main culprits.

Graphite bars can cause dead spots? I hadn't heard of this (seriously, I haven't read every thread). I thought they were supposed to make necks more stable and consistent.

[Turnaround]

A change in mass ANYWHERE on the instrument will affect the instrument's resonant frequency. When the resonant frequency of the instrument (or many fractions thereof) conflicts with the frequency of the note you are playing, you will experience cancellation (dead spots).

You can change the resonant frequency of the instrument in a number of ways, usually by adding or removing mass. And thus you can move the resonant frequency - hopefully for the better.

So, can routing your bass for an extra pickup cause a dead spot to appear? Yes, unless you can route a hole and fill it with a pickup of exactly the same mass as the wood that was removed. Good luck!

[remo]

hmmm, thats what I was thinking...

When the resonant frequency of the instrument (or many fractions thereof) conflicts with the frequency of the note you are playing, you will experience cancellation (dead spots).

to be a real trainspotter...

...Isn't it more the case note cancellation results when the instrument's natural resonant frequency agrees with the note being played... a deadspot occurs when the body/neck vibrates in sympathy with the note being played...

it's the body/neck disagreeing with the played note that lets it sustain.

[Tbirdbassist]

I don't see how routing out space for a pickup on the BODY will effect the NECK in any noticeable way. it's such a small amount compared to the rest... it just doesn't seem plausible.

[PilbaraBass]

Originally Posted by Turnaround

A change in mass ANYWHERE on the instrument will affect the instrument's resonant frequency. When the resonant frequency of the instrument (or many fractions thereof) conflicts with the frequency of the note you are playing, you will experience cancellation (dead spots).

You can change the resonant frequency of the instrument in a number of ways, usually by adding or removing mass. And thus you can move the resonant frequency - hopefully for the better.

So, can routing your bass for an extra pickup cause a dead spot to appear? Yes, unless you can route a hole and fill it with a pickup of exactly the same mass as the wood that was removed. Good luck!

So far, just a theory...
I'm waiting for the formulas and calculations to support this.

IMO...it won't be much at all...taking away that much wood and replacing it with a pickup, will not change the moment (place where the bass balances) much at all, that's easy to check, OR calculate actually.

It would then stand to reason that if the moment is changed little, the resonant frequency is also not changed significantly...therefore, it's doubtful...

trussrod tension, on the other hand, has WAY more effect on deadspots as it affects dramatically the overall stiffness of the neck (hence the resonant frequencies)...

Remo,
If you'd tweaked your trussy at all recently...I'd say that this is where your newly-found dead spot has originated.

[PilbaraBass]

Originally Posted by remo

hmmm, thats what I was thinking...



to be a real trainspotter...

...Isn't it more the case note cancellation results when the instrument's natural resonant frequency agrees with the note being played... a deadspot occurs when the body/neck vibrates in sympathy with the note being played...

it's the body/neck disagreeing with the played note that lets it sustain.

nope...you have it backwards...it's the overall mass (body and neck together as one system) AGREEING with the note being played that creates sustain (or more appropriately, the lack of anything to cancel it out). This is more or less the DEFINITION of resonance.

For an excellent example of this...google the "tacoma narrows bridge" wind excited a natural resonant frequency on the newly opened bridge, and it basically destroyed itsself!

[stanger503]

just gonna throw this in.....screw all the scientific crap just go for it. seriously how many people actually do this....quite a few, i wouldnt worry too much just as long as its like a regular size jazz....not godzilla jazz

[Turnaround]

Originally Posted by remo

...Isn't it more the case note cancellation results when the instrument's natural resonant frequency agrees with the note being played... a deadspot occurs when the body/neck vibrates in sympathy with the note being played...

To be precise, you are right. I was using the term disagree loosely to mean having a disagreeable effect. I'm not sure many folks would understand the damping effect of two systems with the same resonant frequency (string and instrument).

But we are saying the same thing. It's not the neck that has a dead spot - it's the instrument as a whole.

[Turnaround]

Originally Posted by PilbaraBass

nope...you have it backwards...it's the overall mass (body and neck together as one system) AGREEING with the note being played that creates sustain (or more appropriately, the lack of anything to cancel it out). This is more or less the DEFINITION of resonance.

For an excellent example of this...google the "tacoma narrows bridge" wind excited a natural resonant frequency on the newly opened bridge, and it basically destroyed itsself!

You are right in one sense - when the string is vibrating at the resonant frequency of the instrument as a whole, the instrument will vibrate more readily. While it is doing this, it is absorbing more energy from the string than at other frequencies, thus deadening the string vibration. During the resonance no extra engery is created or destroyed - it is only transferred from one mass to another. That's why the string vibration dies at the resonant frequency of the instrument - the instrument is absobing the energy from the string more.

[remo]

just wondering, afaik everything has its own resonant frequence... that being said, how can a carbon fiber neck like on a Zon for instance be called "dead spot free"?? how does the rigidity and uniform weight distribution of a carbon fiber neck differ in dead spots from a wood neck?

[PilbaraBass]

Originally Posted by remo

just wondering, afaik everything has its own resonant frequence... that being said, how can a carbon fiber neck like on a Zon for instance be called "dead spot free"?? how does the rigidity and uniform weight distribution of a carbon fiber neck differ in dead spots from a wood neck?

it's the rigidity...and no it would not be "dead spot free"...just free of dead spots within the frequencies of the bass...

difference between a carbon fiber neck and a wooden neck is simply the properties of the materials in which they are made (again, comes back to rigidity).

[ga_edwards]

I say rout out that body and if a dead spot or two appears get a fat finger. I thought they were gimicky, but after trying one myself, they do in fact work

http://www.groovetubes.com/product.cfm?Product_ID=1200

[remo]

the J pickup I add will have more mass than the wood removed... I already own a fat finger and yest they do help a bit with deadspots, you just have to shift it all over the palce until you find the best point to stop the resonance...