Petrucci electronics question

[jpmrulez]

Hello all!

First of all, my name is Jussi and I'm an eager Music Man Petrucci-guitar player from Finland. I'm a long time lurker, first time poster.

Here's my question: You know this tiny hole that's in the back of the body directly under the tremolo springs? Well I was wondering if there's supposed to be a ground wire coming thru that hole and into the claw the springs are attached to? Because I have no wire what so ever in there and all my other guitars have it. So I was thinking this could be the cause of a little extra hum I have going on when i'm not touchin any metal parts of the guitar.

So if any of you have any advice for me I'd really appreciate it.

Thanks in advance!

 

[peat]

mine has the same home
with nothing coming through it
no idea what its for

 

[Raz]

Hello all!

First of all, my name is Jussi and I'm an eager Music Man Petrucci-guitar player from Finland. I'm a long time lurker, first time poster.

Here's my question: You know this tiny hole that's in the back of the body directly under the tremolo springs? Well I was wondering if there's supposed to be a ground wire coming thru that hole and into the claw the springs are attached to? Because I have no wire what so ever in there and all my other guitars have it. So I was thinking this could be the cause of a little extra hum I have going on when i'm not touchin any metal parts of the guitar.

So if any of you have any advice for me I'd really appreciate it.

Thanks in advance!

I believe the ground for the Petrucci attaches to your shielded electronics cover plate There's a little stiff wire that sticks up and is bent over to sit on the edge where the shielded cover plate sits...

 

[dwf1004]

guides for the CNC in the manufacturing process...?

If so, you have nothing to worry about...it was only used/necessary when your body was being created, carved, CNC'ed...tomato, to-MAH-to...

 

[jpmrulez]

OK, I see.
Thanks for replying everyone

 

[Raz]

OK, I see.
Thanks for replying everyone

Oh dang where are our manners, welcome to the family, and please post pics of your new PET!

 

[beej]

Welcome to the forum!

Sounds like it's normal, but if you're really worried about it get a multimeter and check that the bridge is grounded. Look for continuity or low resistance between the bridge and the ground of the cavity or output jack.

 

[Guitarburetor]

Petrucci ground wire mystery...

Hello all!

First of all, my name is Jussi and I'm an eager Music Man Petrucci-guitar player from Finland. I'm a long time lurker, first time poster.

Here's my question: You know this tiny hole that's in the back of the body directly under the tremolo springs? Well I was wondering if there's supposed to be a ground wire coming thru that hole and into the claw the springs are attached to? Because I have no wire what so ever in there and all my other guitars have it. So I was thinking this could be the cause of a little extra hum I have going on when i'm not touchin any metal parts of the guitar.

So if any of you have any advice for me I'd really appreciate it.

Thanks in advance!

Welcome to the EB/MM forum!

Your Petrucci guitar should have a ground wire to the trem claw. It is soldered to the back side of the claw, so it may not be apparent at first glance. If it is a piezo guitar, the tremolo is also ground via the piezo pickup lead.

You stated that when you touch metal parts of the guitar the hum is reduced, and this is the purpose of grounding the switches and hardware on the guitar. Your body becomes a shield via the ground wire, and if touching the strings causes this change, it would indicate that the bridge is grounded, and functioning properly. You can also test for contiuity with a meter, as is mentioned in another reply.

Hope this helps solve the mystery.

 

[tommyindelaware]

............also lets you feel tingly all over if your playin & sittin on an old 2 prong fender amp in bare feet & shorts....w/ your leg touching that old rusty bar on the top of the amp....& your bare feet on the concrete floor........

if you live through it...ya only make that mistake once !!!!!!!!

 

[beej]

if you live through it...ya only make that mistake once !!!!!!!!

Yeesh. Just ask Keith Relf

 

[Raz]

Welcome to the EB/MM forum!

Your Petrucci guitar should have a ground wire to the trem claw. It is soldered to the back side of the claw, so it may not be apparent at first glance. If it is a piezo guitar, the tremolo is also ground via the piezo pickup lead.

You stated that when you touch metal parts of the guitar the hum is reduced, and this is the purpose of grounding the switches and hardware on the guitar. Your body becomes a shield via the ground wire, and if touching the strings causes this change, it would indicate that the bridge is grounded, and functioning properly. You can also test for contiuity with a meter, as is mentioned in another reply.

Hope this helps solve the mystery.

Oh I thought it was what I explained above...cause I didn't see one on the trem claw (like my SUB 1), I just have, what I thought was that stiff wire that touches the shielded backplate of the electronics compartment...hmmm I stand corrected.

 

[Roxy]

I noticed the small hole on mine too, but just figured it was nothing. Nobody can see it anyways.

 

[jpmrulez]

Oh dang where are our manners, welcome to the family, and please post pics of your new PET!

Thank you very much! Actually I've had my Pet for almost 3 years now. It's just a standar Blue Dawn. No Piezo or matching headstock or anything. Would've liked a piezo though, but the wait would've been like 10 months or so, and this I got in 2 days. Plus this one already cost me 2500€ so I figured I'm good with this one.

It truly is an amazing instrument and plays like a mofo. Also the neck, the pups and the overall feel is superiour to the Ibanez JPM, which I also have.

Oh, and thanks for all the extra tips you guys gave me.
I knew my little puzzle would get solved here

 

[SteveB]

Oh, and thanks for all the extra tips you guys gave me.
I knew my little puzzle would get solved here

Isn't it just so cool when you ask a question about a guitar and the guy who designed that guitar answers?

Man, I love this place!