minnow1281734162 Posted April 27, 2009 Share Posted April 27, 2009 Hi Friends, here is my situation: When playing with a fair bit of gain, buzzing/noise could be heard, sometimes very loudly. If I touch the strings or metal parts of the guitar, it reduces/sometimes completely goes away. I've done loads of reading on this, and common info suggests that it's about grounding/shielding issues. If I touch the bridge and sound goes away, means that my grounding is alright. If the grounding is not alright, me touching the strings wont have any difference, right? But, noise due to shielding issues -> me touching the strings will make no difference on the noise reduction, right? So, please help out and share your opinions, as I am still confused... Attached here is a picture of my stock wiring. Clearly, just normal cables are being used. The black paint is shielding paint right? Is this enough or should I add more shielding (copper/alum foil etc)? Perhaps it is the cables that are the cause of the problem? Can I just trash the current cables and replace them with shielded cables using exact same wiring connections? Or should I re-wire to the star-ground method? Thanks in advance! Link to comment Share on other sites More sharing options...
Gordy01 Posted April 27, 2009 Share Posted April 27, 2009 It's kinda hard to see what is going on there unless you cut the tie and move the wires out of the way. I noticed some of the connections are made with connectors. The large connector could be the source of the problem also. This type of connector is hard to check for proper ground, and is a common source of problems in the automotive industry. If you are getting noise that quits when you touch the strings, or bridge, it is almost certainly a ground problem. It does not have to be in the guitar either. It could be in the cord, or the amp. Or even in the wall connection. Link to comment Share on other sites More sharing options...
RotcanX Posted April 27, 2009 Share Posted April 27, 2009 Hi Friends' date=' here is my situation: When playing [b']with a fair bit of gain[/b], buzzing/noise could be heard, sometimes very loudly. If I touch the strings or metal parts of the guitar, it reduces/sometimes completely goes away. I've done loads of reading on this, and common info suggests that it's about grounding/shielding issues. If I touch the bridge and sound goes away, means that my grounding is alright. If the grounding is not alright, me touching the strings wont have any difference, right? But, noise due to shielding issues -> me touching the strings will make no difference on the noise reduction, right? So, please help out and share your opinions, as I am still confused... There's nothing wrong. The shielding is fine. Sounds like the ground wire to the bridge is present so that's okay too. Basically, as you increase your gain, it's going to get noisy. It comes with the territory. Live with it. Or learn to plain cleaner songs. Link to comment Share on other sites More sharing options...
eezapz2101 Posted April 27, 2009 Share Posted April 27, 2009 It's kinda hard to see what is going on there unless you cut the tie and move the wires out of the way.I noticed some of the connections are made with connectors. The large connector could be the source of the problem also. This type of connector is hard to check for proper ground' date=' and is a common source of problems in the automotive industry. If you are getting noise that quits when you touch the strings, or bridge, it is almost certainly a ground problem. It does not have to be in the guitar either. It could be in the cord, or the amp. Or even in the wall connection. [/quote'] hi i have the same issue with my semi hollow epi ea-250 if i touch the strings the terrible noise goes away on the dirty Channel on the clean channel the noise is not that bad how to know if its the cord or the amp? today i plugged the guitar trough the line 6 pod xt live to the amp and there was no noise ??????? whats going on what to do? i bought a cheap wiring harness from tnt guitars witch i re wired to sd diagrams just to see if the difference in the wiring would solve the problem but noop i even tried to put a cable to the amps conetion cable on the ground pin but no luck so now i dont know what to do an i realy love this guitar but can use it with just an amp alone Link to comment Share on other sites More sharing options...
RotcanX Posted April 27, 2009 Share Posted April 27, 2009 if i touch the strings the terrible noise goes away on the dirty Channel on the clean channel the noise is not that bad how to know if its the cord or the amp? It's not the cord. It's not the amp. It's the technology. And there's no cure for that unless you want to switch to a Classical guitar. Link to comment Share on other sites More sharing options...
carverman Posted April 28, 2009 Share Posted April 28, 2009 When playing with a fair bit of gain' date=' buzzing/noise could be heard, sometimes very loudly.If I touch the strings or metal parts of the guitar, it reduces/sometimes completely goes away. I've done loads of reading on this, and common info suggests that it's about grounding/shielding issues. If I touch the bridge and sound goes away, means that my grounding is alright. If the grounding is not alright, me touching the strings wont have any difference, right? But, noise due to shielding issues -> me touching the strings will make no difference on the noise reduction, right? So, please help out and share your opinions, as I am still confused... Attached here is a picture of my stock wiring. [img']http://i201.photobucket.com/albums/aa93/minnowmfn/LPCavity.jpg[/img] Clearly, just normal cables are being used. The black paint is shielding paint right? Is this enough or should I add more shielding (copper/alum foil etc)? Perhaps it is the cables that are the cause of the problem? Guitar wiring is a high impedance circuit that can't have any lengths of unshielded wire..except the actual connection at the pot. I noticed that there is a 4 pin connector that goes to the 3-way? Although the long run of the wire is shielded, the short side (of the connector) has 3 runs of what looks to be unshielded wire. two of these are from the vol pots and the other goes to the jack. These should not be unshielded even on a short run as it negates the effect of having shielding to the 3-way. Add shielded wires to the vol pots and jack and connect these to the ground pin. As well, the pots, and jack should really have a solid wire connecting them all (star grounding). Can I just trash the current cables and replace them with shielded cables using exact same wiring connections? Or should I re-wire to the star-ground method? Thanks in advance! No you don't need to trash all the wiring in your guitar..just replace any unshielded portions of wire and ensure that both ends of the shield are connected. As well, the ground lug on the 3 way, should have the shields connected to it as well to try and shield the contacts on the 3 way as much as possible. Link to comment Share on other sites More sharing options...
bvarsel Posted April 28, 2009 Share Posted April 28, 2009 Couple of observations. First, all current carrying wires emit EMF waves (electromagnetic field). Proper grounding helps to "shunt" or send these interferences to ground. As we all know, electricity travels by the path of least resistance so a proper ground system will send most of this to ground where it is naturally dissipated. Following this logic if you have a large amount of wire in a relatively small space this will increase the amount of interference proportionatley. So to make a long story longer, only use the length of wire needed to go from point to point. It appears you have enough wire in that cavity to wire 3 guitars! Second, there is not, to my knowledge, any such thing as shielding paint. Link to comment Share on other sites More sharing options...
carverman Posted April 28, 2009 Share Posted April 28, 2009 Shielding paint isn't that effective. I use aluminum foil glued on to the access cover with contact cement and a small stub of bare wire soldered to one of the pots contacting the cover under one of the screws. Link to comment Share on other sites More sharing options...
RotcanX Posted April 28, 2009 Share Posted April 28, 2009 Couple of observations... there is not' date=' to my knowledge, any such thing as shielding paint.[/quote']'Fraid so. Basically it's a paint that has metal particles suspended in it so as to render it conductive. It was originally developed to be used as a coating inside plastic computer housings to impede RF noise. http://www.safelivingtechnologies.ca/RF/Products_RF_Shielding_Paint_HSF54.htm Link to comment Share on other sites More sharing options...
bvarsel Posted April 28, 2009 Share Posted April 28, 2009 'Fraid so. Basically it's a paint that has metal particles suspended in it so as to render it conductive. It was originally developed to be used as a coating inside plastic computer housings to impede RF noise. http://www.safelivingtechnologies.ca/RF/Products_RF_Shielding_Paint_HSF54.htm Sounds kind of cheesy to me........I mean does it worK???? Link to comment Share on other sites More sharing options...
carverman Posted April 28, 2009 Share Posted April 28, 2009 Couple of observations. First' date=' all current carrying wires emit EMF waves (electromagnetic field). Proper grounding helps to "shunt" or send these interferences to ground. As we all know, electricity travels by the path of least resistance so a proper ground system will send most of this to ground where it is naturally dissipated. Following this logic if you have a large amount of wire in a relatively small space this will increase the amount of interference proportionatley. So to make a long story longer, only use the length of wire needed to go from point to point. It appears you have enough wire in that cavity to wire 3 guitars! [/quote'] I enjoy these electronics discussions. Guitar wires don't really radiate any emf per se, as the signal is very tiny, in the order of a few millivolts and virtually no current, well microamps. The biggest problem with hi impedance circuits (500k to 1 megohm) is that the unbalanced guitar cord also acts as an antenna, along with the shielded wires inside the guitar. It's the same effect as having an open ended jack cord..put your thumb over the tip and sleeve and see how the amp reacts. Your body, which acts as an antenna will produce noise into the guitar cord as well. The better the shielding the less noise, is created. When I got my MIK Epi LP Custom, it buzzed a lot. I didn't think it was normal for it to do that. I discovered that the factory had used unshielded wire for the 3 runs (approximately 3 feet) to the 3-way switch...thats like adding an extra 3 feet of antenna wire to the cord jack. Even if the p_up wires were shielded and the shields were connected to the pot cases, it would still buzz. Solution was to replace the unshielded lengths with shielded wire..that stopped the buzzing. Link to comment Share on other sites More sharing options...
RotcanX Posted April 28, 2009 Share Posted April 28, 2009 Sounds kind of cheesy to me........I mean does it worK???? Yup. Link to comment Share on other sites More sharing options...
RotcanX Posted April 28, 2009 Share Posted April 28, 2009 I discovered that the factory had used unshielded wire for the 3 runs(approximately 3 feet) to the 3-way switch...thats like adding an extra 3 feet of antenna wire to the cord jack. Even if the p_up wires were shielded and the shields were connected to the pot cases' date=' it would still buzz. Solution was to replace the unshielded lengths with shielded wire..that stopped the buzzing. [/quote'] The basic rule of thumb is that any wire run over 3" in length should be shielded. Link to comment Share on other sites More sharing options...
minnow1281734162 Posted April 30, 2009 Author Share Posted April 30, 2009 Hi Friends, thank you all for taking the time and helping me out - I really appreciate it. However, I still have lots of questions and hope you all can help me out further... I'll break it into smaller parts, so that it would be easier for you to explain and for me to understand, haha. 1. The connector in my wiring. How can I just be rid of it? And what is the 'source' of the connector - both the pickups? I've collected a few wiring diagrams, and I think I can figure it out but I will only get my hangs on my guitar this weekend. I am asking here just in case somebody here already knows the answer. 2. Ground loops / star ground My plan to create a star ground in my guitar - please correct me if I am wrong: - Unsolder every ground (loop) connection - Solder on a new wire from each component - Connect all these ground to a "common point" and have this connected to the wire that leads to the -ve of the input jack 3. Unshielded Cables Can I just do this to replace my unshielded cables: - Unsolder all unshielded cables - Use coaxial cables as a substitute - Solder the shielding wire mesh of each cable to the pot. Is this a good idea? Thanks again for all your help. I am just looking for ways to improve the situation. Link to comment Share on other sites More sharing options...
carverman Posted April 30, 2009 Share Posted April 30, 2009 I'm sure that you will get ideas from other forum members, but here's mine. Those connectors could be sourced from several manufacturers, most are made in China now, such as Molex, Amp and other US brands. Unless you can find a brand and number on the connector shell itself, you are going to have a hard time matching up the other half. I use molex 5 pin nylon which are cheap and readily available. If you want to remove the connectors, snip them off and splice the ends together and be sure that the wire connections are are shielded. Epiphone should be providing the connector information as a public service. As far as star grounding, I just connect the 4 pot cases together with 22 guage solid wire and the jack frame ground. I connect the tp ground to pot case. The pickups shields are soldered directly to the volume pot cases and the unshielded signal wire is kept as short as possible which is soldered to the pot "taps". One thing I do is solder the shields together at the 3-way and then run a small 22 guage wire to the ground lug on the 3 way. It just looks neater this way. All you need for cables is a good guitar cable, not coax. I prefer to use the vintage Gibson cloth insulated 22 guage wire. It's rugged, and the exposed braid allows you to solder the braid to the pot case directly. You would do this for the 2 (pickup) runs to the 3 way. The output of the 3 way should go directly to the jack frame. Link to comment Share on other sites More sharing options...
animalfarm Posted April 30, 2009 Share Posted April 30, 2009 Attached here is a picture of my stock wiring. I have the exact same connector set-up in my EPI LP Classic. I have a set of GIBSON 498T/490R 2-wire pickups waiting to go in. I have to do a point-to-point trace out of the wiring from each side of the connector to determine if I want to completely remove it from the guitar and just hardwire, or leave in place and put "new" pup wires into existing connector slots. I've used molex in the past, but no longer have the crimpers, pins, etc. I suppose I could buy the factory-style pins (don't what they are yet) then hand-crimp/solder wires to retain the connector as part of the "stock" wiring. I AM curious why EPI went to the connectors vs the usual hardwire from point to point.... Link to comment Share on other sites More sharing options...
minnow1281734162 Posted May 4, 2009 Author Share Posted May 4, 2009 Hi Friends, Sorry it took so long. Had a hard time figuring things out, and I finally managed to get it together last night. Attached here is the wiring diagrams from my guitar. Looks like they're using the shielding for some of the signal cables as ground connections... This is bad, right? This is a picture of the connector whose wirings goes to the pots: This is a picture of the connector that goes to the toggle switch: This is the toggle switch soldering/wiring. Looks like they use the shielding as ground (again): And this is the wiring to the output jack. Shielding as grounding (yet again): Please comment and share your opinions on what I can do to improve on the wirings. I read that coaxial cables are for radio frequencies and that shielded cables are carrying lower frequency cables. I have good quality coaxial cables (meant for electronic circuits' use), will this be a good substitute for shielded cables? Link to comment Share on other sites More sharing options...
carverman Posted May 5, 2009 Share Posted May 5, 2009 Hi Friends' date='Sorry it took so long. Had a hard time figuring things out, and I finally managed to get it together last night. Attached here is the wiring diagrams from my guitar. [img']http://i201.photobucket.com/albums/aa93/minnowmfn/DSC08767.jpg[/img] Looks like they're using the shielding for some of the signal cables as ground connections... This is bad, right? This is a picture of the connector whose wirings goes to the pots: Why use connectors there? If you are going to use connectors, they should be shielded connectors (wrapped in tin foil) and the actual signal wire where it leaves the shield, kept as short as possible, go through the connectors and get shielded again. This is not good shielding IMO. This is a picture of the connector that goes to the toggle switch: This wire does NOT appear to have tinfoil shield and the ground wire alongside the 3 condutors is NOT SUFFICIENT shielding to the 3-way and output jack! wires at the connector, which should be shielded right up to the connector You need to start over with proper 3 conductor shielded wire which has the tinfoil shield..or use 3 separate runs of braided shield wire. This is the toggle switch soldering/wiring. Looks like they use the shielding as ground (again): And this is the wiring to the output jack. Shielding as grounding (yet again): Ok, this is hi-fi wire..not good guitar sheilding cable. The shield strands run inside the jacket and may randomly leave exposed parts of the signal cable underneath the gray plastic jacket. I would NOT USE this kind of wire on my guitars. Please comment and share your opinions on what I can do to improve on the wirings. I read that coaxial cables are for radio frequencies and that shielded cables are carrying lower frequency cables. I have good quality coaxial cables (meant for electronic circuits' use), will this be a good substitute for shielded cables? no you don't need coax..just get some good Gibson vintage shield cable....like this and rewire your guitar..get rid of any unecessary connectors, unless the connectors are shielded properly themselves. use either the Gibson vintage cloth pushback wire with external braid or this type... http://www.stewmac.com/shop/Electronics,_pickups/Supplies:_Wire,_cables/Shielded_Guitar_Circuit_Wire.html Link to comment Share on other sites More sharing options...
bvarsel Posted May 5, 2009 Share Posted May 5, 2009 I AM curious why EPI went to the connectors vs the usual hardwire from point to point.... I would assume that they buy the harnesses already soldered from another source. That way the factory only has to install components and push connectors together. No "technical" labor involved. No "technical" labor = Less labor costs. Also, you can buy several different configurations (i.e. 2 pup 2 vol 2 tone, 2 pup 1 vol 1 tone) with long lead lengths to ensure you can use in different guitars. This would account for the "extra" lengths coiled in the pot cavity. Link to comment Share on other sites More sharing options...
minnow1281734162 Posted May 5, 2009 Author Share Posted May 5, 2009 I would assume that they buy the harnesses already soldered from another source. That way the factory only has to install components and push connectors together. No "technical" labor involved. No "technical" labor = Less labor costs. Also' date=' you can buy several different configurations (i.e. 2 pup 2 vol 2 tone, 2 pup 1 vol 1 tone) with long lead lengths to ensure you can use in different guitars. This would account for the "extra" lengths coiled in the pot cavity.[/quote'] Hi bvarsel, I think you are right on Epi's "outsourcing" method. Link to comment Share on other sites More sharing options...
minnow1281734162 Posted May 5, 2009 Author Share Posted May 5, 2009 no you don't need coax..just get some good Gibson vintage shield cable....like this and rewire your guitar..get rid of any unecessary connectors' date=' unless the connectors are shielded properly themselves. use either the Gibson vintage cloth pushback wire with external braid or this type... http://www.stewmac.com/shop/Electronics,_pickups/Supplies:_Wire,_cables/Shielded_Guitar_Circuit_Wire.html[/quote'] Hi Caverman, Firstly, thanks for all your sharing. I've learnt a lot from your posts on my issue! I read your post last night and did a lot of thinking, and I've decided to just completely rewire. My persistence on the shielding cable is because guitar cables/parts are hard to come by where I live, international shipping is a killer - shipping cost is more expensive than that the item cost. Haha. Anyway, I'm going to go look around for shielded cables and rewire the whole thing! One thing is bothering me - performing soldering in the cavity. I know, this is dumb, as everyone knows - remove the pots and stuff then solder, right? The problem is, I tried to pull the knobs, but I can't. Furthermore I noticed some glue being applied to hold those knobs in place. How? I am determined to rewire the guitar. And the worse thing I'd do is do the soldering inside the cavity - last resort. So wish me luck! Haha. And one last question - why no to hi-fi wire? - because the shield strands may randomly leave exposed parts? Forgive me once again for my persistence on not wanting to get guitar cables (I told you why) but I know where to get good quality hi-fi (speaker) cables that I know will not leave any randomly exposed parts. They're expensive too, but not as expensive as buying guitar cables online and have them shipped to me. Link to comment Share on other sites More sharing options...
animalfarm Posted May 6, 2009 Share Posted May 6, 2009 Minnow, I see by your drawing that you, too have discovered that the only purpose of the connector is to connect the 3-way switch to the body cavity wiring. I just put a set of Gibson 489T/490R in my LP Classic (also with connector), but chose to leave the connector in place as the pins used were unfamiliar, and I wasn't sure of ability to source entire new connector. I used the "lazy man's" wiring - I saw that the pups were wired directly to the pots, so I cut the existing pups wires about 3" from the pots and pulled the stock pups out. I then stripped the stock wires back and twisted and tinned both the ground/shield. Then I soldered the stock wire ground to the shield on the Gibson pups, and soldered the hot wire to hot wire. Wrapped each connection in electrical tape for ease of removal in case I changed my mind later. Plugged git in, tap-tap with screwdriver to verify functional, then carefully bundled and tie-wrapped wires in body cavity. Cover plate back on, new strings - She plays and NOT ONE bit of unwanted noise, hum, etc. A successful operation. Link to comment Share on other sites More sharing options...
carverman Posted May 6, 2009 Share Posted May 6, 2009 Hi Caverman' date=' Firstly, thanks for all your sharing. I've learnt a lot from your posts on my issue! I read your post last night and did a lot of thinking, and I've decided to just completely rewire. My persistence on the shielding cable is because guitar cables/parts are hard to come by where I live, international shipping is a killer - shipping cost is more expensive than that the item cost. Haha. Anyway, I'm going to go look around for shielded cables and rewire the whole thing! [/quote'] Proper braided guitar wiring is the way to go...however, if it's really hard and expensive to get new wire where you are..try wrapping some aluminum tinfoil around the long run to the 3-way and cover the connector as well. If you can solder a stub of solid wire to the ground wire and wrap this stub around the aluminum foil wrapped wire, it might just work. Not going to cost you anything other than some time pulling out the 3-way and wrapping the wire and taping it with electrical tape in a couple of spots. One thing is bothering me - performing soldering in the cavity. I know, this is dumb, as everyone knows - remove the pots and stuff then solder, right? There should be enough room to solder in the cavity with a temp controlled iron. Removing the pots requires some kind of carboard template with the holes in the same spot so you can temporarily solder the pots outside the cavity..it's neater and the wires can be routed the same way as when installed. The problem is, I tried to pull the knobs, but I can't. Furthermore I noticed some glue being applied to hold those knobs in place. How? If these are the speed knobs or bell knobs, and they are glued on, you won't be able to pull them off without cracking them. Leave them on and solder the pots inside the cavity then. And one last question - why no to hi-fi wire? - because the shield strands may randomly leave exposed parts? Forgive me once again for my persistence on not wanting to get guitar cables (I told you why) but I know where to get good quality hi-fi (speaker) cables that I know will not leave any randomly exposed parts. They're expensive too, but not as expensive as buying guitar cables online and have them shipped to me. hi fi wire is ok for short runs inside a stereo. In the guitar..the ground is floating and connected to the amp's "ground plane" through an isolated plastic input jack. This means that the guitar and the guitar cord ground is connected at one spot only..the ground that the preamp uses. Any unshielded wires in a high impedance circuit will pick up noise..the better the shielding, the less noise you will pick up..it's not rocket science. As far as hi-fi wire, if that's all you can get, then try it..but shield the long runs to the 3 way at least..combined the 3 individual wires can be around 2ft or more of unshielded antenna. My MIK Epi LP Custom arrived with unshielded wiring to the 3 way..everything else was shielded. It buzzed and I couldn't believe that Epi at the factory would wire it that way. I redid the wire with a piece of 3 conductor with aluminum foil + ground wire..connected one side of the ground wire to the ground lug on the 3-way, and the other to a volume pot and the buzz is gone. Link to comment Share on other sites More sharing options...
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