New Dark Terror head went silent

[s4t4npt]

Greetings

My new dark terror, that was used like 10 times, just went silent.

Here's the situation, i went to my play room, connected the power, lights on, with the amp on standby as usual, and went to play some drums while I waited for the tubes to warm up.

I was going to try a boss GT1 on the fx loop, used a regular cable to connect the pedal output to the head return, with the pedal power off, amp power on and power output on standby. In the last minute I though: "nah its getting late, let's just play with the guitar strait on the front input for a while and go to bed". Removed the cable from the return channel (pedal never got to power on) checked for the cable connected to the guitar, volumes and gains on minimum as usual and flipped the switch to 15w. Started to increase gain and volumes (amp and guitar) and got no sound. Lights on, rear tubes getting red, front ones don't seem to be changing colour, and no sound.

I don't think there is a reason why the preamp tubes would all die at the same time, the amp is new, I am always carefull, could it be just stuck in some kind of "preamp bypass mode" or something?

I'm starting to panic here, can I get some help please?

[Rlw59]

The effects return jack is a shorting/switching jack. Inserting a plug into it breaks the connection from the preamp to the power amp.

It's possible for the shorting/switching terminal to stick open after you remove the plug. Try inserting and removing the plug a few times and see if the amp starts working normally again.

If you have a can of spray contact cleaner, squirt some in the jack before you insert/remove/insert/remove the plug.

Nothing you did would have damaged the amp. It's possible the amp has a failure that just coincidentally happened. Could be a bad solder joint, could be the phase invertor tube died. But most likely it's just that the jack needs to be exercised a bit.

As long as "new" means brand new (not a used amp that's new to you because you just got it) it's entirely covered by warranty.

[PBA]

It probably didn't like you playing drums

I'd suggest replacing the HT fuse first. If the valves are glowing but there's no sound a blown HT fuse is most likely. Fuses blowing can be nothing significant or can be due to some electronic malfunction. If it's the latter, a valve is the most likely.

[s4t4npt]

Thank you all for the replies. Ended up sending to warranty repair, wouldn't risk opening the amp and voiding warranty.
Rlw59 unfortunately it was not your suggestion, would have been much easier, but the amp was really factory brand new, so I'm using the warranty and saying goodbye for the next few weeks.
PBS, didn't want to risk the warranty by opening it, but I'm sure the cause was the drums... Too late now cheers!