snhirsch

Thanks for documenting. I posted my experience with ground-wire install on a JTV-69 about a year or so back, but am of the wrong generation to instinctively snap photos of everything. Rather than heat-shrink, I wedge a small piece of foam rubber under the string to the rear of the bridge saddle.

My impression (and experience) is that Full Compass really doesn't stock much of anything in terms of Line6 parts. It took me almost three weeks to get a replacement piezo bridge element for my JTV-69.

Gibson QC was wretched in the early 70s. I have no idea why folks are getting such stupid prices for them nowadays.

The 6-string acoustic models sound like an electric instrument. I'm wondering if it's the settings you are using on the Helix? An acoustic model really wants to be run "straight-through" with possibly a bit of equalization and compression. Also, hard to make a call on the Lester bits with that amount of overdrive. I'm particularly interested in what Spank position 2 sounds like through, e.g. a clean Fender Twin emulation. FYI: I have that same Mighty-Mite neck on my JTV-69 and really like the way it plays.

Can you post a recording of the guitar using the Graphtecs?

Do the setscrews line up properly with the little grooves on the bridge plate? I think I remember someone on this forum mentioning a problem with getting the bridge pieces to lie flat because of a small difference in screw spacing.

SteveKC (aka Elantric on the Vguitar Forum) has posted detailed instructions. They worked fine for me when I wanted to roll back from 2.21 to 1.9.

That was my first electric as well. Fond memories of a trip to 48th Street in NYC with my father to pick it up. Mine is long gone, but if memory serves the neck was challenging for my fingers (even at 15 years old I had big mitts).

The aesthetics are roughly on par with the Peavey Autotune guitar.

Why would the Graphtec transducers have more handling noise than the stock LR Baggs units?

Mr. Sarkissian has essentially claimed that the loading effect of plugging the 1/4" cable into an effect box or amp will result in damage to circuit components if the RJ-45 connection is also being used. But, consider for a moment that the RJ connector does not (according to the pinout that's been posted) even carry analog audio. So exactly what is being "additionally" loaded by using both outputs simultaneously (since they have no signals in common)? A mystery for the ages, no doubt. One possible source of problems might arise in a situation where you were trying to power the guitar from both a stereo 1/4" plug and the RJ-45 interface (with, e.g. an HD500 on the far end). But even then any circuit designer worth their salt would place a diode in series with at least one of the power sources to prevent one supply from "back feeding" the other.

The RJ-45 connector on the guitar carries power, MIDI signaling and a 2 channel audio bitstream in AES digital format (mag pickups + modeling output). There's a little diagram floating around that explains the pinout. I believe it was reverse engineered, since Line6 has a policy of saying essentially nothing about the low-level technical details. I would tend to doubt that the programming interface knows or cares about the digital audio and obviously doesn't supply voltage.

Well, in fairness they do not tell you to plug the other end of that 1/4" cable into anything. I guess it's the brutal loading effect of a (typically) 100k ohm load on the analog output IC that would "stress" things.

In the Line 6 bridge? No. They simply bring out the hot lead from each piezo sensor, relying on mechanical contact between dissimilar metals for ground return. This last point makes life rather interesting if you live in a humid environment and/or tend to perspire a lot when you play.

Careful, the Line 6 instruments have a well-known exception to electronic circuit design practices that somehow stresses... something.. if you connect to both outputs. They would explain the physics behind this, but then they'd have to kill you.

That's not a very practical plan. Piezo pickups have far lower output than magnetics and should be connected to a very high input impedance. The GK guitar modules have neither the necessary gain nor a particularly low input Z. You would need a hex preamp between the JTV pickups and the GK-3 to give that a chance of working correctly. And, don't forget the need to filter out subsonic noise from the piezo units (a notorious cause of poor tracking from the GR-55). If you really want to persist with this it's probably best to raise the issue on the VGuitar forums (http://www.vguitarforums.com). A lot of very serious techies hang out there. You'll get a lot of valuable, unfiltered advice.

I had posted a snappy comeback, but then realized that there is no point. Nevermind. You can claim whatever you'd like.

Well, yes, that's what I've been saying from the start. I couldn't believe what I was seeing the first time it happened. The holes are probably out of tolerance on the large side.

That is exactly what I have done every time I've needed to get all the strings off. The upward force pulls out the the pivot pin inserts.

A photo would be worth 10,000 messages. Or, maybe we start with a definition of "behind"? I can see arguments for calling both sides "behind" - depending on your point of view. I've been visualizing "behind" as being on the neckward side of the sustain block. If by "behind" you mean between the sustain block and the electronics cavity, that's another issue and I can sort of picture how it might do the trick.

I'm sorry, but color me sceptical of that claim. Connecting the analog output of the guitar to a typical load is not going to amount to squat in terms of additional current being pulled through anything.

If the bridge inserts are very firmly seated into the body, I agree with your comment. However, even with a shim holding the bridge in neutral position, there is an upward force vector. I happen to be one of the lucky ones with sloppy-sized holes in the body. You can literally pull the inserts out of the guitar with two fingers. I probably should glue them in, but with what? Epoxy is probably too permanent and I'm not sure that wood glue can tolerate a sliding force.

I can see that being a viable option on a vintage Strat tremolo where the pivot screws also retain the bridge plate, but am having trouble picturing how that helps on a JTV-69 where there's nothing to keep the bridge plate up against the pivots. But, if I ever have a need to take all the strings off again I'll keep it in mind.

In my case, a block under the bridge plate didn't do anything about the upward force on the pivots. If the springs are left at full tension you have a surprising amount of leverage trying to lift the inserts out of the body. This is definitely a YMMV. I take pains never to remove all the strings. Haven't been through the exercise since adding pickup ground wires a year or so back and hope never to again.

There's also the issue of drilling a second cable-routing hole in a new location. I don't see this as a good candidate for a retrofit.