Demeter DI box issue/problem

[purpleflyhunter]

Howdy all -

I own a VTDB-2B. The other day at a gig I experienced a breakup of output signal; like that of a battery dying. I took the DI out of the signal chain, used my backup instead, and all returned to normal.

I've done a search on the forum and could not find any directly related material, though, there had been some discussion regarding similar issues of the Demeter preamp.

Was wondering if anyone could point me in the right direction of what may be causing the issue?

I appreciate your help, in advance. Thanks!

 

[Bonafide]

Howdy all -

I own a VTDB-2B. The other day at a gig I experienced a breakup of output signal; like that of a battery dying. I took the DI out of the signal chain, used my backup instead, and all returned to normal.

I've done a search on the forum and could not find any directly related material, though, there had been some discussion regarding similar issues of the Demeter preamp.

Was wondering if anyone could point me in the right direction of what may be causing the issue?

I appreciate your help, in advance. Thanks!

Sounds like your 12AX7 went bad. It happens. Not often, but it happens.

 

[purpleflyhunter]

Thanks, @Bonafide

Might you have a suggestion on a replacement tube? (Preference/opinion)

 

[Bonafide]

I would pop it open and see what James uses. And then search as 12AX7s are hard to get right now. You can likley substitute for a 12AU7 though it is a lower gain tube.

 

[purpleflyhunter]

@Bonafide
I appreciate that. Thank you.

 

[Roxbororob]

Im using a 12AU7 tube in mine (ala Neve/Jules). Less gain but fatter/warmer. Plus I have mine in front of my pedal board (thru a balanced/ unbalanced adaptor) feeding a Slampegg with another 12AU7...

 

[Roxbororob]

Sorry off topic, I agree it's probably the tube that went south in your case.

Edit: Lovely piece of gear

 

[teleharmonium]

It's worth a try to clean the tube pins (with something slightly abrasive like steel wool or a nail file, not anything wet that will leave a residue unless you have some of the Caig labs stuff designed for tube pins).
Most preamp tubes last such a long time that dirty pins or socket contacts breaking the connection will tend to happen before the tube goes.

 

[purpleflyhunter]

Follow up.

Changed the tube...resolved the issue. I had been given good advice to clean the old tube prior to replacement but I had already ordered a new one. The tube in the unit did not look original so I had no qualms about swapping them out. (I kept it, though, just in case.)

Thanks, all!! As always, I appreciate this community and all we do for each other.

 

[seamonkey]

Most all of the problems with tube equipment is solved by changing a tube.
If you take it to a tech, the first thing they'll do is change the tube before doing any other troubleshooting.