X1 preamp problems

After a grid accident, voltage went up (more then 280V iso. 230V) and the X1 preamp combination wasn't working anymore: fuse blown.
With power on, the 250ma fuse blows always when the preamp connected, without preamp no problem PS works.
Whats next to do.
 
If you have and know how to use a multimeter and read schematics, an email to Pass Labs might get you the schematic.
If you also search here, you will find some sage advice from the entire Pass Labs team on servicing and repairing the X1.

Example. https://www.diyaudio.com/community/threads/popping-sound-in-x1-preamp-channel.397938/

Personally, I'd be checking power supply stage for all voltages, damaged diodes and regulators, maybe even damaged caps at that level of overvoltage.
If that is ok, then I'd look at the diodes and regulators in the pre section.

NOTE;
Do NOT plug in, or unplug the umbilical between the power supply and pre sections with out letting the power supply fully discharge first.
Doing so is known to damage the pre section.
 
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If you don't want to go to Pass Labs for help (as many have suggested) and persist with asking the questions here on forums, you'll have to understand that we can't comment on something without a photo or 2... Agree??

You can also search the forums for X1 pre-amp.... related to the UserAbuse post re: damage to the logic circuit/ICs due to incorrect power-down & disconnection of the umbilical cord.

Or, you can contact Wayne Colburn from Pass Labs. He is always very helpful and frequent here on forums.
 
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@ UserAbuser
1) You're better technician as I am ! ????
2) But you are not a specialist in politeness, since when do you have the right to judge ?
3) I am 66y and started building and experimenting with amp's and all kind of electronics when I was 12.
4) My studies and career: @ 12 electrics & mechanicals, @ 15 electronics, @ 18 technical school of the airforce (avionics and radar), @ MMSC Huntville Alabama and back to the airforce school with a lot studies allover in Europe. In Germany I was responsible for trouble shooting , repair and upgrading electronics. Later I was involved in prototyping, developing and application of new board.
5) In I started a repair and sales shop specialist in "better sound & vision" (PASS LABS, Klipsch, Arcam, Von Schweikert, Musical Fidelity Harman Kardon & many more).
I was known for the repair of the "irreparable" esp. Accuphase & Luxman.
@ 2009 I became a head technician specialized in PA and communications for the Belgian national railways.
6) All the time untill now I am busy with building and repairing.
6) So indeed I am stupid in electronics, but I've no big mouth, I was just asking an opinion before attacking a PASS

Enjoy it
 
even better

so, as I said above, just contact PL directly, ask them for schmtcs

most likely you'll find toasted reg or two in preamp case, due to reg input overvoltage

now, depending of luck, damage can be just that..... or more

edit: for first step you don't even need schematics; let's just hope that you don't need them to dig deeper
 
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