Hum from Lace Sensor: is this normal?

[huntgl]

I have replaced the 6 pole pick up on a Squier Bronco Bass with a Gold Lace Sensor, which I have wired directly to the jack as follows:

Red wire to hot pole
Green (ground) to ground pole
White (phase) to ground pole
Black (body ground from bridge) to ground pole

I am getting some noise when I plug this in, very much like the noise you get when alot of treble is applied, but I have been told by the tech guy at Lace that it should be silent. Does anyone know if this noise is because I have bypassed the volume and tone pot (and is normal), or is because I have wired it incorrectly or badly? Thanks...

[dd842]

huntgl said:

I have replaced the 6 pole pick up on a Squier Bronco Bass with a Gold Lace Sensor, which I have wired directly to the jack as follows:

Red wire to hot pole
Green (ground) to ground pole
White (phase) to ground pole
Black (body ground from bridge) to ground pole

I am getting some noise when I plug this in, very much like the noise you get when alot of treble is applied, but I have been told by the tech guy at Lace that it should be silent. Does anyone know if this noise is because I have bypassed the volume and tone pot (and is normal), or is because I have wired it incorrectly or badly? Thanks...

Hi huntgl, and Welcome! to GN2

That sounds right ... but just in case, do you happen to have any pictures that you can refer us to before commenting further?

I would hate to think I am thinking of something different than you are asking about.

Thanks,
Dan

[hammeroff]

I'm with Dan on this one, (by the way, welcome to the forums!)

If posting pics isn't an option though, there's just a few things that could eliminate some confusion for me...

First of all, was this noise there with the old pick-up? Or did installing a Lace Sensor increase your noise level?

Next, are we talking about a single Gold Lace Sensor? Or a "dual" (humbucker) Gold-Gold combination?

If the noise was there before the Gold-Lace Sensor, it's very possible that a simple ground loop, or lack of shielding is causing the noise.

[huntgl]

Thanks for the replies and welcome messages!

It is a single Gold Sensor. When I first wired it in, I wired it through the volume and tone pot like the original pickup. When the tone was set to full treble, it made the same level of hum as it does now, but when it was set to full bass it was silent. I have to admit that I never plugged it in with the old pickup, so I cannot compare it to that (I bought it second hand and took it to pieces straight away to upgrade some components). I have some photos, but I can't figure out how to attach them here. I have put them on a page of my web-site www.noluckyman.com/plaintext.html, which I hope works ok?

I've not done much soldering, but I'm pleased with the job I've done on it. I'm running it into a very good pre-amp/DI/channel strip and listening through headphones, so that may be the problem, but I have been led to believe the Lace Sensors were silent. I don't mind if that's not the case, but I just want to make sure I've done the best job possible in wiring it in. Maybe I should change the pots to 250's and go that route again or maybe I need to shield it properly or use a different way of grounding it?

Thanks again...

[dd842]

huntgl said:

..... It is a single Gold Sensor.

okay

I have to admit that I never plugged it in with the old pickup, so I cannot compare it to that (I bought it second hand and took it to pieces straight away to upgrade some components).

;D ... are we related?

I have some photos, but I can't figure out how to attach them here. I have put them on a page of my web-site www.noluckyman.com/plaintext.html, which I hope works ok?

That's fine, but for future reference here is how you do it:

[img src="i101.photobucket.com/albums/m51/dd842/Free_Dog.jpg"]

Wow! I'm digging your songs, dude!

I've not done much soldering, but I'm pleased with the job I've done on it. I'm running it into a very good pre-amp/DI/channel strip and listening through headphones, so that may be the problem, but I have been led to believe the Lace Sensors were silent. I don't mind if that's not the case, but I just want to make sure I've done the best job possible in wiring it in. Maybe I should change the pots to 250's and go that route again or maybe I need to shield it properly or use a different way of grounding it?

Thanks again...

It could be the shield ... but I want to draw attention to the little wire that runs from the volume pot's terminal to it's case ... only I am not exactly sure why I am drawing your attention to it.

Would it be much of a pain to try: 1) disconnecting that wire to see what happens, and if that is worse or not better, 2) running a wire from that terminal to the output jack's ground sleeve? I don't know if either will make things better, worse, or just do diddly ... it would be just to see what happens ...

Dan

[huntgl]

Thanks for the thumbs-up; I appreciate it.

I've taken that wire off and it makes no difference. What would sheilding it involve and would it be worth it? Excuse my ignorance...

[dd842]

Thanks for the thumbs-up; I appreciate it.

I've taken that wire off and it makes no difference. What would sheilding it involve and would it be worth it? Excuse my ignorance...

What I was concerned about with that wire was a ground loop ... incidentally, if it makes no difference having it there, you may not want to put it back on.

Most of us are still learning here ... certainly I am still learning. So no need to feel ignorant.

Speaking of ignorance, I admit that I do not own a bass and have no experience shielding them.

Nevertheless, the principal should really be the same - so check this out so that you have a good idea of the main objective of shielding and how to do it.

I noticed in one of your pictures that the shield runs under the jack and the two pots, but then rounds off (as if it comes to an end) - does it end where it rounds off?

You will see from the shielding instructions that you are not just trying to block out interference, you are trying to block out interference by creating a shield that has electrical continuity (using the shield as the conduit). The shield should cover the back of entire pickguard, so that the jack, pots, and the screws on the pickup can all make good contact with the shield, and the shield should cover the entire pickup/control cavity AND should make good contact with the shield on the pickguard. The whole thing should be electrically connected - except the signal is insulated from the shield.

I hope I am explaining it properly ... you should read the instructions over the weekend first so you are familiar with them before we risk a mutually multiplied magnetic misdemeanor.

Dan

[huntgl]

Thanks very much Dan, you're a true gent!

[dd842]

huntgl said:

Thanks very much Dan, you're a true gent!

Gary,

Right back at ya!

Have a nice weekend.

Dan

[sumgai]

Dan,

...........
You will see from the shielding instructions that you are not just trying to block out interference, you are trying to block out interference by creating a shield that has electrical continuity (using the shield as the conduit).

That should read as "..... block out interference by creating a shield that has both magnetic and electrical continuity." The noise we all dread is electromagnetic in nature, so we need to take out both sides of the equation, or our efforts are in vain.

Nonetheless, you did have it correct, even though you didn't fill in all the blanks.


(And how did you get from 'huntgl' to Gary? )

huntgl,

Hi, and welcome to the Forums! Dan (dd842) and Matt (hammeroff) are doing right by you so far. Pay moderate attention to their babblings, and all will go well for you and your axe. ;D


sumgai

[dd842]

sumgai said:

Dan,

...........
You will see from the shielding instructions that you are not just trying to block out interference, you are trying to block out interference by creating a shield that has electrical continuity (using the shield as the conduit).

That should read as "..... block out interference by creating a shield that has both magnetic and electrical continuity." The noise we all dread is electromagnetic in nature, so we need to take out both sides of the equation, or our efforts are in vain.

Nonetheless, you did have it correct, even though you didn't fill in all the blanks.

Thanks for setting me straight on "magnetic" - and, yes, I didn't even want to get into anything else until he has looked at J.A.'s instructions (having said that, look at the images Gary has provided for us here: www.noluckyman.com/plaintext.html ... the bass seems to have some elements of proper wiring even now)

I also neglected to mention, in my image insert instructions, that he needs to first either upload his desired image to photobucket or wherever (another site or could use his own site) and then copy that url as the internet address (image) that the image command is to display.

(And how did you get from 'huntgl' to Gary? )

I have the force ... okay, well, more like “force-ight” really, to click here www.noluckyman.com/plaintext.html and see the name that Gary has copyrighted his site under.

By the way, click on his first song "Reaching Outwards" - good guitar playing, and a good voice. He's got potential.

huntgl,

Hi, and welcome to the Forums! Dan (dd842) and Matt (hammeroff) are doing right by you so far. Pay moderate attention to their babblings, and all will go well for you and your axe. ;D

sumgai

Matt, I won't speak for you, but I think sumgai had a lot more credibility before he said that about me ;D

Dan

[huntgl]

Dan,

Thanks again for the kind comments mate. Spread the word and all that....

I've had a good read through the shielding article; thanks for that. I plugged in my Tokai Strat (1984ish) to the pre-amp/DI to check the noise levels on that, and the bass is definitely noisier than the Tokai running through the middle pick-up with treble full on, so I think there's probably more I can do with the bass. I am thinking of upgrading the pots to some good quality 250's and re-wiring as suggested by SeymourDuncan:

www.seymourduncan.com/support/schematics/single_coil_pbass.html

In your opinion, is there a better way of wiring this than this schematic suggests?

Thanks again,
Gary.

[dd842]

I am thinking of upgrading the pots to some good quality 250's and re-wiring as suggested by SeymourDuncan:

www.seymourduncan.com/support/schematics/single_coil_pbass.html

In your opinion, is there a better way of wiring this than this schematic suggests?

Thanks again,
Gary.

Hi Gary,

There is no harm in upgrading the pots. But I would imagine that shielding will be more rewarding.

I think you can nearly get away with the SD wiring, but you have some shielding and really should totally shield so long as you are in there. But the wiring should be a little different.

I think if you follow these steps you should be okay:

1) shield the pickup and control cavities (use copper foil or tape, ideally, but aluminum foil or (real aluminum metal, not aluminized cloth) duct tape will also work)
2) shield the entire pickguard (Note: I am assuming the pickguard covers the control cavity AND the pickup cavity ... if it doesn't, let me know)
3) ensure the cavity and pickguard will make electrical contact with each other
4) ensure the pots and the screws on the pickups have electrical contact with the shielding
5) eliminate ground loops (Note: see comments below)
6) The SD diagram shows a tremolo ground, so if you have it you may want to run the tremolo ground to one end of the 400 V cap and the other end of the 400 V cap to the ground sleeve of the output while you are in there (see below)

After shielding, there will be two ground loops that I can see if you wire as done in the SD diagram:

One that you have already checked into, which was the wire that ran from the tab to the back of the volume pot. Recall that you disconnected it and there was no difference - so just leave it off (in the SD diagram, you will see that they have soldered the tab to the back of the pot, which is the same deal ... you don't need this with shielding).

The other is the wire that runs from the back of the tone pot to the back of the volume pot. You don't need this if you are shielding - and you don't have one on right now, so don't put one on.

We have not spoken about the .33uF 400v DC blocking capacitor yet ... and I won't go into detail other than to say it protects you in the unlikely event that there is a fault with any vintage amp you may happen to use, while singing your heart out, while standing in a mud puddle (okay, I made that up) ... but it's cheap and it's easy to put it in, so maight as well do it also.

Take a look at the modified diagram below, and see if it is clearer now:

Dan

P.S. I am a little pressed for time today, so I think this is all okay ... but ... you might want to wait and see if it draws any friendly fire first

[huntgl]

Dan,

I'm going to crack on with the shielding an re-wiring later this week and I will let you know how it goes. Is there an article about that capacitor on the guitar nuts site? I seem to remember one somewhere.

I want to say thanks again to yourself and everyone that's chipped in to help. I really appreciate all the comments.

All the best and see you soon I hope,

Gary.

[sumgai]

Gary,.

............
Is there an article about that capacitor on the guitar nuts site? I seem to remember one somewhere.

Yes, it's integrated with the "Quieting the Beast" article, you'll have to pick through it a bit, but everything you want/need to know is there.

HTH


sumgai

[huntgl]

Dan, Sumgai et al

It turns out that the problem is with the DI unit, as I shielded and re wired it, and it still made the noise. I took it to a guy to run it through a bass amp and it was quiet as a mouse (dead silent in fact), so it must be the headphone channel that is humming!!! Live and learn and all that.

Anyway, it's shielded now and looks great, so hopefully that will pay dividends down the line.

Thanks again to all concerned.....Be lucky!

Gary.

[dd842]

huntgl said:

Dan, Sumgai et al

It turns out that the problem is with the DI unit, as I shielded and re wired it, and it still made the noise. I took it to a guy to run it through a bass amp and it was quiet as a mouse (dead silent in fact), so it must be the headphone channel that is humming!!! Live and learn and all that.

Anyway, it's shielded now and looks great, so hopefully that will pay dividends down the line.

Thanks again to all concerned.....Be lucky!

Gary.

Good stuff, Gary - yup, it will pay dividends for sure.

Not only is your equipment and knowledge of electonics now in better shape than it was, you also have the satisfaction of knowing you stuck with it and solved your problem.

Sometimes it turns out to be an oddball issue that noone really saw coming. You worked it through and eventually diagnosed the problem ... live and learn, as you say.

What is rewarding for us is that you shared your findings ... so we get to learn too.

Glad it all worked out - don't be a stranger!

Dan