Variax Acopustic 700 problem

[gmcgann]

Well, my third Acoustic 700 is dying, with the same problem that killed my other two. I load all my models and tunings with workbench and it works fine until I unplug it. Next time I turn it on all the alternate tunings sound like crap because the mix is about 50%. I can open it in Workbench and it's still set to 100, but I'm getting at least 50% of the actual string tuning. I turn the mix down and then back up in workbench and it's fine again. I save everything to the guitar, and every once in a while it will work once after that, but for the most part it only works until the power cycles. I assume this means the main board is failing, but with three of these doing the same thing I'm wondering if it's a common problem. It does it with both new batteries and power from the power supply.

[psarkissian]

When using the VDI mod connector, remove the batteries.

 

 

[gmcgann]

This isn't a power problem.

 

[psarkissian]

I ask because, the board failing that way can be a result of using having batteries in the unit while

using the VDI mod cable. The over-voltage from having both connected can damage a couple of board

components over time. Which can affect performance of certain functions.

 

Save Workbench patches to your computer, then re-Flash the guitar firmware, then reload the

patches from Workbench to the guitar (or keep the re-Flashed factory defaults).

 

Or, it could be a piezo thing. Carefully cleaning the piezos with cotton swab and alcohol (try not to

get it on the wood) in the piezo and saddle. Dust or debris can get in the saddles and interfere with

the piezo casing-to-chassis ground connection.

 

[gmcgann]

That makes no sense on any level. To begin with, the owner's manual, page 5, says, "if you have batteries installed in your Variax Acoustic, they will be bypassed when using your XPS direct box." The VDI cable will not power the guitar. It might on the 2nd gen stuff, but not this one. So is the manual wrong?

Your second paragraph describes what I have to do each time I use the guitar.

The third paragraph makes no sense. The pickups obviously work, it's what the board does with the signal that's the problem.

[psarkissian]

1) 700 series, using the XPS isn't a problem, it's when one uses VDI while the batteries are still in the unit.

There is a component that, if it breaks down over time, the battery bypass may not function like it's suppose to.

If using TRS tip cable and XPS, haven't seen a problem with that, bypass should work.

 

2) Shouldn't have to do that each time. Something is not function there. Sounds like that needs to be looked at

by a Line 6 authorized service tech.

 

3) Doesn't happen often, but it does happen. The whole piezo array can attenuate, or just an individual piezo.

Also old strings that don't have sufficient pressure on the pizeos can attenuate the signal.

 

Could be a loose connection somewhere on the inside. May be time to log a Support Ticket for its 50,000 mile

check-up at your local Line 6 authorized service tech, or the Line 6 tech.

 

[gmcgann]

1) So there is a design flaw that destroys the guitar. Some engineer thought it would be a good idea to wire the XPS power and the battery power in series instead of in parallel. That's the only way the voltage could increase.

 

2) Yes, that's the problem.

 

3) So exactly how can a weak piezo signal affect how the board processes the signal in referenced to the altered tuning? And how can changing the mix from 100% to 99% and then back, which fixes the problem temporarily, in software, affect the piezo or the string pressure?

[psarkissian]

1) Not a design flaw, as much as a parts thing.

 

3) Intermittent chassis ground can result in a host of problems.  3b) String pressure on on the piezo is where everything begins, everything else stems from that. Your problem is that it's not a single cause. There is a cause and the rest of the circuit is reacting to it. 

 

Log a Support ticket and arrange to have it serviced.