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WHAT!?

#62
DavidRavenMoon said:
Your body has too high a resistance to act as a ground connection... plus you are not in your bare feet on concrete. You touching the strings does help ground your body I suppose.
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This is what I was trying to say.

DavidRavenMoon said:
No, because it still takes away hum if you are not touching the bass.

Leave it sitting on a stand, and disconnect the ground wire to the bridge. Hear the hum?
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A ground connection might reduce the hum on its own. But because you put yourself at zero potential when you touch grounded strings you are acting exactly the same as big piece of shielding you cover a big area than just the bridge and strings. RFI hits you and travels to ground. Whilst you have high resistance and make a bad ground connection the signal will take the easiest route to ground. That is not through you through your shoes and carpet to the floor. It goes through you (after putting yourself to zero potential by touching the strings) and on to the strings and then on to ground. You still have a high resistance but this is the easiest path to ground for the signal.

I do know that my musicman is one of the quietest instruments I've come across. I also don't fancy pulling my bridge off or desoldering ground connections on my more noise suscetable jazz bass.

What I will try when Im home is induce noise from my PC on to my jazz bass and then touch something grounded thats not my bass like my PC chasis and see if that reduces the hum.

BTW I'm not trying to say that not grounding the bridge and strings is a bad idea. I'm aware that it can present a very real shock hazard.
 
#63
a typical J-bass utilizes a pair of single-coil pickups. when both are set to equal volume they cancel RFI because the pickups are reverse wound and reverse polarity. you will hear increased noise when one pickup is set to a greater volume than the other

contrast this with your MM which has a pair of RWRP single-coil pickups together in one pickup to reduce the noise. if you want to have your MM on parity with a solo pickup on the J-bass, utilize the coil tap switch to cut out one of the two coils. now you should be able to hear the true difference between basses

all the best,

R
 
#64
Rodent said:
a typical J-bass utilizes a pair of single-coil pickups. when both are set to equal volume they cancel RFI because the pickups are reverse wound and reverse polarity. you will hear increased noise when one pickup is set to a greater volume than the other

contrast this with your MM which has a pair of RWRP single-coil pickups together in one pickup to reduce the noise. if you want to have your MM on parity with a solo pickup on the J-bass, utilize the coil tap switch to cut out one of the two coils. now you should be able to hear the true difference between basses

all the best,

R
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The sterling utilizes a phantom coil which is used to reduce noise when in single coil mode. It just wont get noisy! :D
 
#65
AlphaMale said:
I happen to believe to happen I have acquired a lot of knowledge over my fews years living. If I knew everything, I wouldn't be asking questions on a forum, I'd think you'd figure that out on your own. But I'm not educated on electrical engineering, and I don't claim to be. The same way you demonstrated you're not educated on manners.
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It's your name, Alpha. It comes across as a neon challenge and asserts that you are some sort of top dog. As long as you call yourself "the boss", folks will react. Just my .02
 
#67
i got a hole too!!! :( :b

IM000509.jpg
 
#68
#69
theshadow2001 said:
Wont an RCBO or GFCI as they are called over there in the main electrical board pretty much cause a a trip if any of those 3 instances occur?
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I suppose that would be situation based too, not every club/venue has gfci's, though you'd be more likely to see surge protectors. Depends where you go, i'd imagine. Sometimes it may depend on the local electrical codes in different areas and when (what decade) it was put in.
 
#70
theshadow2001 said:
The sterling utilizes a phantom coil which is used to reduce noise when in single coil mode. It just wont get noisy! :D
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I know exactly that pickup

b-mm43_back.jpg


having that extra dummy coil sure does make things quieter for the player

all the best,

R
 
#71
#72
Rodent said:
o - and guys/gals ... lighten up. those of us who live here in the Luthier's Forum don't take kindly to the rude behavior in this thread (and a couple others here lately) ... if you can't play nice go somewhere else (like OT) where that childish behavior is tolerated ... that kind of immature behavior is NOT tolerated in this house
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+1

T2W stated a fact and was assaulted by quite a few. Those of you who can't play nice, GTFO.
 
#73
I did my little test. So I held my jazz bass up near my PC with a single coil on. There was a higher pitched sizzle and a low hum.

When I touched the strings the higher pitched sizzle disappeared. I reached around and put my hand on the heat sink of my speakers which are grounded without touching the bass and it had exactly the same effect as touching the strings.

The low hum remained through out.

Rodent said:
if you play with meatl strings and have not absolutely assured with a testor that the wiring is ok at this specific stage on this specific night ... drop the string ground and keep a finger on the strings between songs - 60Hz EMI buzzing goes away, and you live to play another night
R
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This suggests to me that a ground needs to be present in order to touch the strings to stop the RFI although it doesn't matter what ground you touch it doesn't have to be grounded strings.

Although to be certain I'd have to disconnect the ground from the bass. Which I'm not going to do.
 
#74
DavidRavenMoon said:
...the potential is never different enough to cause a ground loop.
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I have had instruments with ground loop issues. Back with I started playing, I had a P-bass that hummed, which it shouldn't as it's hum-cancelling... even when the bridge was grounded, if you touched the strings, hum got louder, as opposed to going away. Had to re-wire everything, checking each connection to make sure that I had it right.

I usually wire up my basses with the bridge grounded. As mentioned above (the Guitarnuts link), some people use either a .33uf capacitor or even a .02uf capacitor to isolate the shield ground from the signal ground, and that this *can* limit the current from the jack in (although that isn't the intent). Of course, if you have lethal voltage, and you touch the jack or plug, no amount of modification of the internal circuitry does you any good...
 

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