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Do You Have The Same Problem With 6th String?

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28 minutes ago, dukeofdream said:

 

Yeah and that really is a shame :/ I made peace with my 89F having the plink... The only way to get rid of it would be to swap the board and hope for the best... So yeah, good luck with that i guess xD I was reading about a guy who sent his guitar over like 4 times and they always either did nothing or swapped the piezo pickup of the Low E... BTW i took the time to test the same piezo pickup on all 6 connections on the board... My 89F also has the plink on other strings, its just not apparent the way the other strings are tuned... I do laptop and console board repair for a living and i thought i could give it a shot to try and diagnose the pcb... The problem is that L6 uses proprietary chips and of course there are no schematics available...

 

I have found some schematics of the old gen variax and if it's anywhere close to the 89F then the pcb devides the strings in 3 groups and feeds it to 3 l6 made proprietary chips, each chip handling 2 strings(the same chip is also used in some line6 amps)... Each piezo pickup has to pass through a circuit with resistors, caps and an amplifier... It could very well be a faulty resistor that's causing all these issues... I really don't know how line6 approached this issue but if you give this guitar with this issue to a guitar technician to figure it out, then good luck... This issue needs to be solved by an electronics engineer who also understands stuff about guitars... After so much searching and saving money for so long to get my 89F i really can't afford to brick it(Given the fact that if i do brick it i will most likely never get my hands on a new board). If someone could sacrifice a guitar for testing out a potential fix to this issue i would be happy to try and give it a shot i guess lol :P

The only "safe" fix i can think about is swapping the low E string connector with another string that doesn't have the issue and it wont be as apparent once it does...Then take the time to reprogram all alternate tunings to the new layout...

Again such a shame to have this issue and have no other alternatives... I bought mine knowing about the potential problem since there's no other guitar on the planet that can do what the variax does... For now i made peace with it, i mostly use the mags and only use the modelling for crunch tones or alternate tuning ONLY i really have to...

Can you provide links to the old gen Variax schematics?  It sounds like the piezos go to regular op-amp ICs.  The resistors and caps are probably just filtering circuits prior to going into the op-amps.  If they are incorrectly spec'd, they could potentially cut off certain frequencies; they are less likely to cut out altogether unless a cap is bad and shunting the signal to ground.  With an oscilloscope, one could take a look at the signal after the op-amps, and then strum the associated strings to see if the op-amps are clipping the signal at a certain amplitude.  

Does the plinking sound occur more readily if you hard pick or strum the strings with more energy versus a softer fingerpicking style of playing?  

The problem with most modern PCBs is they use surface mount technology and micro components that are nearly impossible to replace by your average Joe.  You will need a low temperature solder rework station to remove the ICs that might be causing the problem ($3K-$5K).  It could be that during manufacturing, they used too high of a temperature to mount the ICs and in the process they damaged the op-amp circuits that the piezos feed into.  But if that is the case, it might be a relatively easy fix for an experienced repair technician, provided the op-amps they used are commonly available; a circuit schematic would help determine if they could be substituted with something else.  The last thing Line 6 wants is a recall action; something a class action lawsuit could only enforce.  I think the first step is to find an electronics engineer with QA experience in the manufacturing of PCBs and have them take a closer look at what is going here, they might discover the root cause through a visual inspection and give justification to pursuing it legally. 

Unfortunately, I couldn't find a part number for the main brain of the Variax guitars.  I would imagine that the central PCB is common across all models, and if it is the culprit, it would explain why the issue isn't with just one guitar model.  Did the previous versions suffer this phenomenon too? (i.e. 300, 600, 700 series)

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36 minutes ago, novumlucis said:

Thanks for the responses.  That certainly clarifies things a bit.  If it is across all lineups, and swapping the E and A wires moves the problem to the A wire, then it is probably an electrical issue.  My guess is the summoning circuitry has a bad transistor, and it is clipping.  I'll know more when my guitar finally shows up. 

 

Having worked electronics for many years, the most common problem with cheaper electronics that have been outsourced to China for their production is cold solder joints on the PCB.  Many times the root cause is in the post production, where they don't clean the printed circuit boards with a cleaning solvent.  The fluxes used in the soldering process are acidic and with time they degrade the solder connections.  If you look at the solder joints they should be shinny; if they have a dull look to them, they are at least suspect.  I like to use alcohol and a toothbrush to go over the solder contacts to see if they cleanup.  And then with a high power magnifying glass I look very carefully at the connections I suspect.  If I see a bad joint, I use a low power needle soldering iron and re-heat the junction, then clean again with alcohol.  This trick fixes most issues 75% of the time.  The other 25% of the time you will need to de-solder the component and re-affix with fresh solder.  I'll post back here what I find in my guitar. 

 

I don't want to rain on your parade, but all you'll find is a mystery... and that's if the specimen you happen to get has the problem in the first place. It's a common, years old problem that likely has numerous contributing factors, particularly the tone you're using (higher gain makes it worse), playing technique, pick attack, etc... which would help explain why some guys have the problem and some don't. Whatever the cause(s), it's far from universal...and if it could be solved with a soldering iron and/or rubbing alcohol, that would have been discovered long ago. The simple truth is that it's imperfect (and now decade old) technology... for all the things it does well, it's still got a long way to go.

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5 minutes ago, novumlucis said:

Can you provide links to the old gen Variax schematics?  It sounds like the piezos go to regular op-amp ICs.  The resistors and caps are probably just filtering circuits prior to going into the op-amps.  If they are incorrectly spec'd, they could potentially cut off certain frequencies; they are less likely to cut out altogether unless a cap is bad and shunting the signal to ground.  With an oscilloscope, one could take a look at the signal after the op-amps, and then strum the associated strings to see if the op-amps are clipping the signal at a certain amplitude.  

Does the plinking sound occur more readily if you hard pick or strum the strings with more energy versus a softer fingerpicking style of playing?  

The problem with most modern PCBs is they use surface mount technology and micro components that are nearly impossible to replace by your average Joe.  You will need a low temperature solder rework station to remove the ICs that might be causing the problem ($3K-$5K).  It could be that during manufacturing, they used too high of a temperature to mount the ICs and in the process they damaged the op-amp circuits that the piezos feed into.  But if that is the case, it might be a relatively easy fix for an experienced repair technician, provided the op-amps they used are commonly available; a circuit schematic would help determine if they could be substituted with something else.  The last thing Line 6 wants is a recall action; something a class action lawsuit could only enforce.  I think the first step is to find an electronics engineer with QA experience in the manufacturing of PCBs and have them take a closer look at what is going here, they might discover the root cause through a visual inspection and give justification to pursuing it legally. 

Unfortunately, I couldn't find a part number for the main brain of the Variax guitars.  I would imagine that the central PCB is common across all models, and if it is the culprit, it would explain why the issue isn't with just one guitar model.  Did the previous versions suffer this phenomenon too? (i.e. 300, 600, 700 series)



The plinking occurs no matter how you handle your picking, i can even make it happen by just softly touching the string with my pick without it even making any other sound except the plink... It's more of a very high pitched artifact... The pcb is the same across the entire jtv family but i hear they are "branded" differently at the factory... They kinda use a different tuned firmware for each body the pcb goes into... Again this is what i have heard, so i'm not sure... I have a Variax 500 that has the same issue on the low-E string but it's not that bad... I could swear the guitar was fine until i got my 89F(in which i noticed the plink right away). Then i tried with my 500 to see if it does the same and there it was... Just much less apparent hence i never noticed until then... The plink is more obvious the higher the gain so my theory is that all JTVs could potentially have this issue but not everyone uses their guitar for high gain tones... The 89F is a model that is mostly purchased by people who use high-gain tones so they can tell right away... I gave my 89F to a friend and he didn't notice anything.. You know why? Cause he plays jazz and country xD Never uses a high-gain tone.. Me on the other hand i mostly practice Dream Theater so i could tell from the first minute...

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11 minutes ago, cruisinon2 said:

 

I don't want to rain on your parade, but all you'll find is a mystery... and that's if the specimen you happen to get has the problem in the first place. It's a common, years old problem that likely has numerous contributing factors, particularly the tone you're using (higher gain makes it worse), playing technique, pick attack, etc... which would help explain why some guys have the problem and some don't. Whatever the cause(s), it's far from universal...and if it could be solved with a soldering iron and/or rubbing alcohol, that would have been discovered long ago. The simple truth is that it's imperfect (and now decade old) technology... for all the things it does well, it's still got a long way to go.

No worries, it is hard to rain on my parade...unless you talk about my BMW...now that car's electronics get me down!  LOL...  Anyway, I find that most experienced luthiers aren't experienced in the repair of complex SMT type PCBs.  Also, I doubt they have the equipment to diagnose the highly complex circuitry found on those boards.  However, I'm sure there are a few out there, with a BS/MS in electrical engineering, but I'm also sure they are far and few between.  And it is less likely that they've had one of these Variax guitars in their hands, and were willing to take on a possible electronics problem without schematics, if they did.  You would be surprised how much stuff gets manufactured in China, where corners have been cut in QA/QC to underbid the next guy.  One of those corners cut is washing the PCBs after soldering.  So yes, a solder iron and rubbing alcohol can go a long way to fixing quirky bugs in electronics.  The problem with Surface Mount Technology (SMT) components, is what you don't see...a cold solder joint between a pin (or multiple pins) that are positioned under the component where it meets the landing pads on the PCB.  You can't even inspect these visually; you can only test them electrically by using a highly complex automated test station which injects various signals at one end of the circuit, while measuring the outputs at the other end.  These systems use a matrixing process and compare measurements against known good values for the PCB under test.  This isn't typically done for every PCB manufactured (unless it is MILSPEC manufacturing), but done on a random sampling basis using statistical analysis in a QA/QC approach.  But again, the lowest bidder who probably manufactured these Line 6 components, isn't doing this type of testing.

Think about this...the open Low E has a much lower frequency than the other stings.  It could be possible that this low frequency, relative high energy wave is vibrating the PCB in the body of the guitar and causing an unseen cold solder joint to respond to it.  Or maybe it is just how the piezos are responding to this low frequency energy, or a harmonic thereof. 
E = 82.41 Hz, A = 110.0 Hz, D = 146.8 Hz, G = 196.0 Hz, B = 246.9 Hz, E = 329.6 Hz

 

Just out of curiosity, does anyone have any experience with the Ghost bridge products from GraphTech; specifically their Rose Floyd bridge?  If yes, have you ever experienced the "plinking" sound this thread is talking about, in a guitar that has been outfitted with such a Ghost bridge? 

What about the JTV-x9 US models, is there issues with those as well?  I know I would be highly upset if I bought a "boutique" guitar with this problem out of the case!  


I can only hope that Line 6 discovered the problem and then had newer higher quality parts manufactured to use as replacements in their warranty repair department.  I doubt it though...and my refurbished JTV-89F will probably have this same issue everyone is talking about.  If it does, then I will need to decide within 90 days to keep it, or send it back.  Either way, I will definitely take a peak inside.  ;-)  

Final thoughts...If Line 6 discovered this problem "long ago", now that the company has changed hands and is owned by Yamaha, do you "REALLY" think they have a vested interest in bringing it out and publicly acknowledging it?  Doing so would be catastrophic for their retailers and the brand's image, not to mention it would open them up to class action lawsuits, and heavy devaluation of their inventories.  No, I'm sure they would just perform a silent fix of those covered under warranty, and all others they would just let the consumer suck up the loss.  Or maybe it is like you say, an imperfect 10 year old technology that Yamaha is still pedaling, despite its flaws.

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19 minutes ago, novumlucis said:

No worries, it is hard to rain on my parade...unless you talk about my BMW...now that car's electronics get me down!  LOL...  Anyway, I find that most experienced luthiers aren't experienced in the repair of complex SMT type PCBs.  Also, I doubt they have the equipment to diagnose the highly complex circuitry found on those boards.  However, I'm sure there are a few out there, with a BS/MS in electrical engineering, but I'm also sure they are far and few between.  And it is less likely that they've had one of these Variax guitars in their hands, and were willing to take on a possible electronics problem without schematics, if they did.  You would be surprised how much stuff gets manufactured in China, where corners have been cut in QA/QC to underbid the next guy.  One of those corners cut is washing the PCBs after soldering.  So yes, a solder iron and rubbing alcohol can go a long way to fixing quirky bugs in electronics.  The problem with Surface Mount Technology (SMT) components, is what you don't see...a cold solder joint between a pin (or multiple pins) that are positioned under the component where it meets the landing pads on the PCB.  You can't even inspect these visually; you can only test them electrically by using a highly complex automated test station which injects various signals at one end of the circuit, while measuring the outputs at the other end.  These systems use a matrixing process and compare measurements against known good values for the PCB under test.  This isn't typically done for every PCB manufactured (unless it is MILSPEC manufacturing), but done on a random sampling basis using statistical analysis in a QA/QC approach.  But again, the lowest bidder who probably manufactured these Line 6 components, isn't doing this type of testing.

Think about this...the open Low E has a much lower frequency than the other stings.  It could be possible that this low frequency, relative high energy wave is vibrating the PCB in the body of the guitar and causing an unseen cold solder joint to respond to it.  Or maybe it is just how the piezos are responding to this low frequency energy, or a harmonic thereof. 
E = 82.41 Hz, A = 110.0 Hz, D = 146.8 Hz, G = 196.0 Hz, B = 246.9 Hz, E = 329.6 Hz

 

Just out of curiosity, does anyone have any experience with the Ghost bridge products from GraphTech; specifically their Rose Floyd bridge?  If yes, have you ever experienced the "plinking" sound this thread is talking about, in a guitar that has been outfitted with such a Ghost bridge? 

What about the JTV-x9 US models, is there issues with those as well?  I know I would be highly upset if I bought a "boutique" guitar with this problem out of the case!  


I can only hope that Line 6 discovered the problem and then had newer higher quality parts manufactured to use as replacements in their warranty repair department.  I doubt it though...and my refurbished JTV-89F will probably have this same issue everyone is talking about.  If it does, then I will need to decide within 90 days to keep it, or send it back.  Either way, I will definitely take a peak inside.  ;-)  

Final thoughts...If Line 6 discovered this problem "long ago", now that the company has changed hands and is owned by Yamaha, do you "REALLY" think they have a vested interest in bringing it out and publicly acknowledging it?  Doing so would be catastrophic for their retailers and the brand's image, not to mention it would open them up to class action lawsuits, and heavy devaluation of their inventories.  No, I'm sure they would just perform a silent fix of those covered under warranty, and all others they would just let the consumer suck up the loss.  Or maybe it is like you say, an imperfect 10 year old technology that Yamaha is still pedaling, despite its flaws.

Give me your email, i couldn't find a way to pm you...

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1 hour ago, dukeofdream said:

novumlucis give me your email, i can't find a way to pm you ...

It is my username + @gmail.com

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1 hour ago, dukeofdream said:



The plinking occurs no matter how you handle your picking, i can even make it happen by just softly touching the string with my pick without it even making any other sound except the plink... It's more of a very high pitched artifact... The pcb is the same across the entire jtv family but i hear they are "branded" differently at the factory... They kinda use a different tuned firmware for each body the pcb goes into... Again this is what i have heard, so i'm not sure... I have a Variax 500 that has the same issue on the low-E string but it's not that bad... I could swear the guitar was fine until i got my 89F(in which i noticed the plink right away). Then i tried with my 500 to see if it does the same and there it was... Just much less apparent hence i never noticed until then... The plink is more obvious the higher the gain so my theory is that all JTVs could potentially have this issue but not everyone uses their guitar for high gain tones... The 89F is a model that is mostly purchased by people who use high-gain tones so they can tell right away... I gave my 89F to a friend and he didn't notice anything.. You know why? Cause he plays jazz and country xD Never uses a high-gain tone.. Me on the other hand i mostly practice Dream Theater so i could tell from the first minute...

Does the "plinking" occur through a Variax cable into a Helix, or does it only occur through the analog TS cable from the 1/4" jack?  

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