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Volume/0ot pot for Mags only

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Does anyone here know if it is possible to instal a volume/tone pot for the mag pickup and still feed it through the same jack?


In another words disconect the mags from the default pots and add to the new concentric pot in order to have infinite control over the blend on the go. But through the same output jack


Ok before anyone start preaching,


Im on firmware 1.71 and the new sounds on the new hd does not suit my gig. Simple.

I know it is possible to blend mags with the new firmware and yada yada yada.

But soundwise the new firmware just doesn't suitme.


Oh also my guitar is not under warranty and not afraid of experimenting here


Any help in achieving the above would be highly appreciated


Thanks in advance

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No doubt it is absolutely possible that you can wire it up if you're not afraid of experimenting. Disconnect the mags from everything and solder in new vol/tone/selector switches and connect it in parallel would be my guess. The rest of this post takes a different look at it, so it may not be worth your time if you are committed to your original approach.


I started thinking about this question and after 2 minutes it started to make my brain hurt. It would require dealing with several issues, some of which I'm sure I don't know about. If you keep the signals separate, you should be good to go. The ability to blend is the result of the VDI cable. The signals are kept separate until they hit something like the 500X. The thing is, I think they are digital in that Variax Digital Interface. Feeding both analog signals through the same jack is the problem. My Majesty can do it, but it has a crap load of electronics in it designed to do just that. Maybe that could give you some clues that would help for you original approach. 

I think they already use a stereo jack for the whole power engagement setup. If you figure another way of turning on the power for the electronics, you could run a stereo cable into your multi-input floor modeler and do your blending within your preset. The mag input probably goes into the model selector switch first to turn off the mags when model mode in engaged. If that's the case, I would disconnect there, use separate vol/tone/selector switch into the tip or ring side of the stereo jack and use the other for the models. You most likely want to separate the acoustics into an FRFR cabinet anyway if you are feeding the mags into a tube amp. This would still let you blend any of the other models with the mags to go wherever you want them to go via your preset. 


I would like to know what you end up doing, and how it turned out.

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It's do'able. Just need to be aware of a few things relating to

phase, phase distortions and impedance, and know how to deal with it.


Two signal paths with differing impedances, just have to make certain

they are are correctly matched.


I thought running the mags and models at the same time was verboten. Did Line 6 change their position on this? 

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Ja, das ist sehr verbonten,... when running both signals thru the main board at

the same time. Load and impedance issues.


If it is the separate line he seems to suggest to the 1/4", detached from the main

board, then that's an isolated circuit.


It will still have to be impedance matched between the signal from the main board

and the separate mag circuit.


Will still have issues of controlling the signal levels. 



And Line 6 does not endorse modification of its products.

So this is as deep as I can get into this, some advice of what not to do.

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Hey guys

Thank you so much for all your inputs, I really appreciate it

Yeah so my idea is to detache the mags and add an vol/tone concentric pot (a separet circuit through the same output.

Oh but seems like I would need a separate 5 switch ?? My guitar is the Jtv 69

Psarkissian , would you be able to give me some pointers as to how I could match the impedance?

@ Cruision2 ha ha ha Loved your humour, maybe a microwave would def be easier


However the more I think about it, more simpler ways to at least give it a go comes up. For instance I would not go ahead and drill holes and butcher the guitar, instead just unsolder things and try it with the eletronics just hanging rather than a definitive modification


I've already modified the guitar by changing the neck and pickups (dimarzio area 58,67,61)

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There are many ways to impedance match. Should be left to a tech with experience and knowledge

in this area.


Line 6 does not endorse modifications, and I can't get deeper into circuit level aspects beyond this.

Just here to make you aware of a few technology caveats.


This is not something to be attempted by anyone not experienced with the in's and outs of this product.

I see many to many failed attempts come across my repair bench.


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Yes, I'm the guy at Line 6 who repairs JTV's, Standards and Shurikens,

along with a host of other gear. Done my share of custom guitar work.

Most I can do is try to keep everyone's trial and error down to a minimum

of errors. So be aware of what all of you are getting into.

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Talking to a friend tech he is positive that a Fshman powerchip may solve the impedance issue


Our only doubt though is that fishman instructs to use their own 9 pin output jack. Not sure what effect that woukd have as far as powering the models

Any thoughts ??

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  • 2 weeks later...

Psarkissian , any advice on this would be greatly appreciated man.



I emailed fishman and explained my idea..... because my main concern now is ....would the signal from the variax piezos (modeling) be too hot for the powerchip? The powechip is actually a preamp designed to boost a najef piezo and blend with mags.

Their response was (the person responding did mention not familiar with the specifics on the variax biard) that it could indeed be too hot since the current circuit on the guitar is already amped and the current electronics arealready capaple of blending. So basically the old firmware is just not letting me have fun :-(


It now makes me wonder how did people achieve the old variax transplants and got magnets pickups to blend .

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Old Variax guitars didn't have mag pick-ups, so was never an issue.

Those who have done transplants that I've seen, have maintained that

and not used mags in conjunction with their piezos.


Those that have done JTV transplants, were techs who have experience

and intimate knowledge with JTV electronics. Not a whole lot of 3rd party

electronics inserted in between. Too many chances for impedance mis-matches 

and other like problems.


I've seen my share of failed attempts come across my repair bench.


Blending is usually done working with Workbench HD. Also proper pick-up

height adjustment helps. Seen too many guitars come back after I've serviced

them because somebody altered the settings and set-up, went beyond spec

and tried to hot rod it. Spec is set the way it is, because that's what works.


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