Community: Message List

Re: JTV-69 and Line 6 VDI cable: problems with 12 string tracking

support@line6.com — Mon, 12 Dec 2011 19:54:07 GMT

Interesting...

This might be related to the issue I described here : http://line6.com/support/thread/71849?tstart=60

If I'm right, the problem could be coming from the power being provided by the POD (through the VDI cable).

Maybe the POD power line is too noisy (typically battery power is noise free), disturbing analog circuitry (both mag pickups and piezo used for models), and causing tracking issues on the 12 string models.

Fredo.

Re: Noises with magnetics when using VDI cable

support@line6.com — Sun, 20 Nov 2011 09:57:58 GMT

About the quoted "feature" word, I must confess it's just me teasing Line 6 and trying to pump up the subject to give it more priority in their TODO list ;-).

The answer I got is coming from Line6 Europe and is about the same as the one Eddie got from Line6 UK: they reported the problem to Line6 US and are waiting for an analysis from them.

My answer was in French, but they were talking about a known issue of all the JTVs with no solution at this point.

I have some (limited) knowledge in electronics, and I fear that the issue is a wrong design in the power stage of the DSP board (probably missing a RF/EM filter, and disturbing the analog pickups when powered with an unclean DC power source (POD vs. battery pack)).

When I'll find some time I will try adding a RF/EM filter on the power line of the VDI cable to check this theory.

Unfortunately, if I'm right, no firmware update will be able to fix this, and I don't think that Line 6 will patch the DSP board of all the JTVs out there !...

Maybe they will provide a special VDI cable with the filter in it ?...

Regards,

Fredo.

Re: Noises with magnetics when using VDI cable

support@line6.com — Sat, 19 Nov 2011 20:19:26 GMT

I don't buy it that the noise I have is just normal single coil noise. The JTV-69 and my Strat are both quite fine with 1/4 " cables. The VDI is the problem. I even bought some really stiff shielded ether cable and made my own VDI - same problem. FWIW, I play live in a couple of different spaces weekly and the noise is no different in either environment.

Actually the noise is not coming from the signal being transferred through the VDI cable but from the guitar being powered by VDI.

See my thread on this here : http://line6.com/support/thread/71849?tstart=0

You can make the test yourself : plug your guitar to the POD or to an amp with a standard 1/4" jack cable => everything is fine. Then, keeping the 1/4" jack plugged, just add the VDI connection, and here it comes: big hiss/noise even on the signal coming from the 1/4" jack cable.

Line6 support told me that it's a normal "feature" of all JTVs and that they don't have a solution for now...

Sad enough.

Regards,

Fredo.

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Wed, 02 Nov 2011 19:49:38 GMT

Well thanx for the update Eddie.

I'm glad you got a replacement guitar that solved most of the issues !

So far no news for me on the hiss on mag pickups with VDI cable, but your new guitar seems to confirm that it's a design issue rather than a faulty guitar...

I do not use mag pickups for now (too noisy), which is a bit of a shame, but I hope that Line6 will find a solution.

If I find some time, I will try adding a RF/EM filter on the power line of my VDI cable to see if it helps (but really this job should be done by Line6 engineers, not by me !...).

Cheers,

Fredo.

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Fri, 07 Oct 2011 19:26:18 GMT

Hi there,

I just received an answer from Line 6 support and wanted to share with you (I translated from French):

We have reproduced the same noise issue during our tests, so far this behavior is normal for JTVs and is not a specific issue with your own guitar.

We are still waiting for more inputs from Line6 US on this matter.

Right now, it is not recommended that you return the guitar to you retailer.

Not sure if this is a good news or a bad news...

The good news is that they may work on a solution since they managed to reproduce the issue (will they ?).

Still it is strange that not all the JTVs are affected, according to Eddie's testimony (and I'm sure we would have seen more complaints on this forum if everyone was affected).

I hope the will find a software solution because I don't want to send my guitar back (unless it is replaced right away).

Wait and see...

Fredo.

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Tue, 04 Oct 2011 20:42:16 GMT

Hi Eddie,

Sorry for the delay.

So here are my conclusions to the tests :

- I have a slight hum on mag pickups with standard jack cable, for positions 3 and 5 only (but much less disturbing than the noise of the VDI cable),

- I do hear a small fizz when I touch the bridge or the strings, but like I would on any other guitar,

- Same hum with VDI cable on mag pos 3 and 5, but it's covered but the noise of the VDI cable,

- I do hear some noise on RESO position 4, but small.

Hope this helped...

Any news from the support for you ?

For me, the last message was Spet 29, saying they sent the information to the support team in England (I'm in France)...

Cheers,

Fredo.

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Thu, 29 Sep 2011 20:41:38 GMT

Hi Eddie,

Same here, I got noise on the following models :

- Chime position 2 and 4,

- Acoustic position 2 and 4,

- Custom2 position 2, 3 and 4.

Boooooh we're damned !...

Cheers,

Fredo.

P.S.: First session with the band and my new rig last night. I love the sound of the DT50 and the neck of the JTV 69 !! 8-) Line6 rocks... sometimes !

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Wed, 28 Sep 2011 15:29:14 GMT

Eddie,

OK so it seems that we both have the same issue :-(...

Likely we're not the only ones, but this thread shows that the problem is not that easy to point out !

Anyway your experience with the first JTV proves that mag pickups should be working silently event with the VDI cable plugged in.

My JTV69 serial # starts with W1107, so likely not the same batch as yours.

Maybe it has something to do with the firmware version ?

I am running the last update (1.71 I think).

Fredo.

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Wed, 28 Sep 2011 14:51:09 GMT

Yes that's exactly what I meant !

And in your case you must have a noise suppressor on the patch, that's why the hiss like pulses, as it must be near the threshold level of the noise supressor.

OK so this seems to be a design issue with all the JTV, not only mine...

The mag pickups are just as silent as the model sounds, but some "sshhhhhh" noise comes in the way when the JTV is powerd through the VDI cable.

Can anyone else confirm ?

Re: Big hiss / noise on mag pickups when powered via VDI

support@line6.com — Wed, 28 Sep 2011 14:41:58 GMT

@Jayson : I tried removing the USB cable, but it had no effect... still big hiss :-(

@Eddie : Yes in my case it's realy not a ground loop hum but rather a high frequency hiss.

Attached is the recordig I made for line6 support.

First part without VDI, second with VDI, and third without.

Cheers,

Fredo.