novumlucis Posted February 23, 2021 Share Posted February 23, 2021 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) Quote Link to comment Share on other sites More sharing options...
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.