psarkissian

JTV-89, made in 2012.
No service history.
 
Check Knowledge Base for general information on JTV's.

Hay un cortocircuito o una conexión intermitente entre la tarjeta de control y la tarjeta del procesador.
Tendrá que ser atendido por un centro de servicio autorizado de Line 6 que conozca el producto.
 
No es algo que un usuario final deba hacer, ya que hay pruebas y comprobaciones que deben
hacerse después, que los técnicos de sesrvice hacer.
 
(via Google Translate)
 

No way to go direct. No power amp within that can drive speakers.
JM4 is instrument output level. can't drive speakers on it own.
 
JM4 --> power amp with instrument or guitar input --> speaker
 
JM4 --> Active Speaker with an already amp in it.
 
... would be the options here.

You need the battery if you are using the 1/4" TRS connection to plug into the Helix.
You don't need the battery if you use the VDI connection with the VDI cable.
 
The Model encoder has an internal switch, you push down on to engage the Models.
Some people forget that, and they think that it simply plug in and turns on, on its own.
 
Also, check to be certain that the Helix is not controlling the JTV-69. Check the Edit Page
Variax settings for that.

Got the specs off of the 89F drawings.
Slight correction, borrowed calipers from a lab-mate,...
 
24.4mm was at the end of the fret-board, just before the head-stock flare.
20.2mm at fret-1 (not including fret height)
20.15mm at fret-12 (not including fret height)
 
... measured from a spare 89F neck I have here, with a more recent serial#.
A more recent spec.

"... while back because it had some discoloration on side of the tube, like slight burn mark"---
If it has a burn mark on the side, then it's "red plating",... remove the tube. There is a problem with
the plate element and can damage other circuits.
 
"... would putting those Groove Tubes in hurt the amp or just wear out quicker?"---
Love GT's, Aspen Pittman, who started Grooves Tubes is a friend and colleague. These are not all
analog tube amps of the 1960's and 70's, you can't go swapping out for any tubes like we used to
back in the day. These are optimized for EH's. Need to use the specified EH's. 
 
If it's "red plating" it needs to be serviced and checked for any other problems. And the specified
matched set of tubes need to be put in and properly biased. Can't mix and match tubes like that,
the amp will be damaged. Unmatched tubes result in distortions, which results in rapid wear-and-tear
on the amp. Even more so since this is not an all analog tube amp of old.
 
DT series amps that come back to me for repair and servicing with other than specified tubes in them,...
... come back to me because of use of the afore mentioned un-approved tubes (Mesa, GT, JJ, and
the odd Ruby and Tung-Sol).

Yes, Audio Master out of the Minibrute to the Line In.

http://www.fullcompass.com/prod/114557-Line-6-11-11-0001 

White noise suggests a high noise floor, and that goes to gain or an impedance mismatch between devices.
 
If it's a Mackie board, chances are there is an input trim pot for adjusting level between mic and line inputs.
Most other board will have phantom power. You may want to start with phantom off, until you can determine
whether it is having an affect on the signal.
 
Phantom power is meant to be used for condenser mics.

Don't do it, they are not designed for that kind of use,
they're made for high fidelity stereo, not high power guitar stuff.
 
I used to sell and service JBL speakers and other of their products,
I even worked there a while. I know their stuff. Don't use them with
a DT series amp. They aren't made for that. If you buy them, use
them for something else.
 
If you plug them into the DT and at some point the speakers blow,
it will take the amp down with it,.... and that will cost several times
more than $100.

Noise floor.
 
Ground loops are possible,...
depending on what else is in the signal path
and how it's plugged in,

Are you using a TRS 1/4" cable?