Post by RollnROCK89i on Jun 15, 2005 19:21:41 GMT -5
Hello, I just finished doing the QTB mod on my Fender MIM Tele. I know that I did this perfectly, cavity's completely covered in foil, no ground loops. This got rid of the interference noises, such as light dimmers, computer monitors, and other types of things like that considerably, but I still have a very loud 60 cycle hum. This 60 cycle hum is still there when i lift the control panel out of the guitar, so i know that its not because of something accidently contacting the shielding that shouldn't be.
I know that it is 60 cycle hum because it isn't crackely, its a constant hum. I was looking around the interent and found out that 60 cycle hum is a little flatter than b flat, which this hum is(used my tuner), so I have confirmed that this is 60 cycle hum. (info on this here: www.sfu.ca/sca/Manuals/ZAAPf/h/hum_interference.html)
From what I gather, this is being caused by the power somehow, but I don't know how to stop this.
When I move the guitar, the loudness of the hum changes. When holding the guitar, front facing upward, if I tilt it different ways, it either gets louder, quieter, or stays the same, but its always there.
I can recomend Australia, but it may casue its own hum problems.
I see no one has thought of anything else. I assume that the hum is more than normal single coil hum. Its hard to answer because if the wiring is in fact perfect, then theres no problem to find!. Youll have to do some detective work to narrow it down, it might mean trying things like directly connecting the pups to the jack, one at a time, without any switches etc. to try to isolate the problem.
Anything is possible. Apart from the hum, do all of the sound settings sound normal? each pickup and combined? Since it seems to vary as you move the guitar, it is likely to be some induced noise that the guitar is picking up, rather than the amp or building wiring. I think it is most likley something that should be grounded that isnt, due to a bad joint or wiring error (everyone makes them!), or something connected to the output that shouldn't be. Is your sheilding grounded? and the bridge? You need to get into some detective work, testing each pup on its own directly connected to the jack. Also test resistances of each pup, and of the guitar as a whole in varous switch combinations. If you can post some more symptoms, then we can help more.
Post by RollnROCK89i on Jun 20, 2005 13:03:48 GMT -5
The only way the wiring is bad is if it came stock like that. The 60 cycle hum was there before I even opened her up. I didn't mod any of the wiring either, all I did was add shielding and connected that to ground. I also made sure that all of the shielding was taped down tight so that it wouldn't touch any of the wiring.
I'm gonna plug in the guitar somewhere else other than my house to see if anything changes. If not, I guess pickup testings next.
yes check you ground on the outlet you are using also go over your work on the guitar one more time (step by srep ) sometimes you can overlook a small wire or a wire can come undone when your putting it back together . also take it to a guitar store and plug it in to a amp and if it still has the hum its the guitar .
I have the same problem with my strat. I actualy just started a new thread on it. I feel stupid for not first searching the forum for this. Sorry about that but if you find out how to fix it please let me know. I did the QTB mod too and it didn't help and it stops humming significantly but not completely when I turn it a certain way. It only hums like that in the 1,3, and 5 positions and can hardly be heard in clean mode or in the 2 and 4 positions. I hate it.
Last Edit: Jun 28, 2005 20:22:03 GMT -5 by stratman
I see no one has mentioned the obvious - have you checked your patch cord ground? Do your amps have a ground reverse switch? Do your amps hum like that with just the cord connected, with no cord connected? Do you have continuity between the shielding foil and the output jack ground? Between the ground pin on the patch cord and the grounded part of the guitar? Is there a difference when you touch the metal parts of guitar or have no contact?
thanks for adding 'em, but I believe that most of fellow members living in the America uses 3-plug socket system, right?
Yep. It's actually required by the building codes. If you have an older house, say from the 60's and earlier, then you may still have the old 2-prong plug but anything newer than that had to be built using 3-prong.
Post by soldercaster on Jul 18, 2005 11:46:52 GMT -5
Hey I've had the same problems in the past, Tried "Everything" and eventually ACCIDENTALLY solved the problem with a powerstrip!! that I borrowed for a gig. This powerstrip was also a "power conditioner", not just a 6 outlet strip though it looked like it and not an expensive rack mount job either. My friend gave it to me and to date it is one of my most valuable pieces. No hum. It might be an "obvious" to most, but it was news to me back then. I hope this helps
Post by RollnROCK89i on Jul 19, 2005 10:17:12 GMT -5
I'm gonna try to answer everyone's questions.
Lets start with the amp, I have the amp plugged into a power strip, which is grounded. The powerstrip has a light indicating that there is a ground connection on it, this light is currently lite. The amp is on my normal volume, which is somewhat loud. There is hardly any hum and extra noise right now. I connect a 10 foot cord into the input. With the cord connected, there is slightly more noise than before, but nothing to complain at all about. Lets say I connect my dual humbucker guitar, the noise level stays prety low. I can play with a lot of gain and volume without any problem from extra hum and crackling. Their is absolutely no 60 cycle hum with this setup. This is true for both my solid state amp and my tube amp.
Let's say I connect the tele to the amp now. As soon as it is connected, there is a very loud 60 cycle hum, which is quite annoying. Touching the metal parts of the guitar, strings/knobs/control plate do not effect this noise at all. Changing the pickup to the neck/bridge/both have no effect on the 60 cycle hum.
The noise before I shielded the tele was two different things, crackling noises, such as the kind that light dimmers cause, and the 60 cycle hum, this has a pitch slightly under b flat, so it has been confirmed as 60 cycle hum. The shielding got rid of the crackling noise, but not the 60 cycle hum. This is where I am stuck.
What exactly is a power conditioner? I might look into this, as I'm out of ideas. I could not gig with this guitar in the current state, the hum is just way to much. Thanks.
Post by soldercaster on Jul 19, 2005 23:09:43 GMT -5
A Power conditioner "cleanses" the power coming into it, like a filter and it's circuitry is designed to maintain a constant voltage. A power strip is just an extension cord w/6 outlets. Even though you have an indication of ground in your power strip, it doesn't necessarily mean it is a "good" ground. The temptation to conclude it is the guitar that is the problem is kind of a half truth. That guitar doesn't like what you're feeding it. Neither did my strat. Some clubs were fine, others I couldn't hear myself think! IF there is a problem in the guitar's shielding, the power conditioner may not totally eliminate the noise. However, it is a worthwhile investment (you should have one on your PA system as well )- especially if you are playing in the bars and clubs, where many times the owner's girlfriend's cousin "Knows all about wiring" and runs the power to the stage, unknowingly tieing it in to the same circuit as the lighting and the beer cooler (now everything's buzzin' except for the frustrated guitar player!). It will solve those kinds of noise problems and probably will solve the problem, if any, residing in your house wiring.
You should be able to get one at just about any local music store, and perhaps a computer store. It's also not a surge protector although there are models available with...
Hi guys, Have you thought about plugging your amp into a power conditioner? My LP's were making a ton of noise in my new house (which is actually very old, so it's not properly grounded) So I asked the tech at my local guitar shop and he recommended a power conditioner. I'm not sure how it works or if it might affect your tone, but this guy used to be an electrician so I took his word for it (I was just too cheap to buy one yet)
I'm on exactly the same quest as RollnROCK89i - where does my 60 cycle hum come from... and I might say that I'm experiencing the same kind of phenomena: in function of the location and the position of my guitar, the hum gets louder or more quiet (but never goes away) (The guitar I'm talking about has the QTB mod on it). Today, a frienf of mine came by with his oscilloscope and he discovered that the frequency of the hum is 180Hz !!! He suspects that something might be wrong with my amp (=Marshall AVT 275); I don't have two amplifiers, so, has anybody an idea how I might test this?