Problem with Z12 and VH4 - DEAD? -solved-

[dotkill]

Hi everybody,

i´ve bought a used VH-4 from a friend recently.
Everything was more than perfect but today the amp did not "start up".
All other gear connected is working fine (Engl Z-12 Midiboard, FX in parallel-loop) so i think there was no power-failure or anything.

There´s the normal humming inside, all tubes are glowing but all front-lights are dead and there´s no sound.

i checked the tube-fuses and the fuse on the main power-plug. Everything ok.

Maybe anyone can give me advice what this issue could be.

Lots of thanks in advance,
Oliver

 

[FIREBALL]

does it have a secondary fuse.....like a ht1 o t1a

 

[dotkill]

i don´t think so. maybe internal, but i´ve read somewhere here, that there are no internal fuses in the VH-4.
All other fuses are ok.

 

[FIREBALL]

i have you put new pre amp tubes

 

[Ultradeaf]

Are you running any pedals with the amp? Sounds like you may not have continuity. Could be a cable as well. $4 cable with a $5000 amp is not a good idea.

 

[dotkill]

Pedals are all fine. Unplugged them all. Cables are not the problem (Vovox).
the amp is simply not starting up....

 

[Peter Diezel]

It would be not the first time that the Z12 blows
an internal fuse because it has a different
pin connection concerning the phantom power.
The official pins are 3 for plus and 1 for minus
for all other manufactures.

So if You have plugged Your Z12 without
rewiring the leads for phnatom power You
can be sure that this is the issue.

So Your headline should read "problem with Z12"

Please UNPLUG the amp and take a look to the
smaller midi board. There are two fuses and it
looks like one of these is blown.

Best regards,
Peter

 

[dotkill]

Hi Peter,
thanks for your quick reply.
YES, one fuse is blown. I will get a new one on monday and change it. i will post, if this will be succsessful.

But one question regarding the Z12 an MIDI:
I use a standard MIDI-Cable (5-pin) with no Phantom Power. It worked well for weeks now.
The MIDI Jack on the VH4 has 7 Pins. So i suggest, that the other 2 "non-standard(?)" pins are phantom-power?
So, do i still have to rewire my standard-MIDI-cable when i´m not using phantom?

1000 Dank!

 

[dotkill]

Oh ja.
The blown fuse is the same as the spare-fuse in the main-power-plug. (Someone knew what he was doing, right )
so i fixed it. amp is running again.
Thanks a lot!

I found the attached sceme for the MIDI-pin connection on vh4 and engl.
But, as written above, my vh-4 has 7 pins... confusing. can you help?

 

[Peter Diezel]

Pin 6 und 7 are also for phantom power
like units as the Midi Mate.

Pin 1 and pin 6 = Ground
Pin 3 and pin 7 = +12 volt / 0,8 amp
Pin 4 and 5 = midi data

Best regards,
Peter