Epiphone Valve Standard - Dropped --> VERY loud Whine/Hum

[gibson05]

The title pretty much sums it up. Epiphone Valve Standard. ~2-3 years old. It fell over, dropping about a foot and half before landing on carpet. Now, when it is plugged in (with no other electronic devices around), there is this terribly loud, sharp whine. With no cables plugged in, I can turn the volume from off (no noise) to high with the noise becoming almost unbearable before half-volume. In comparison to most online discussions regarding "hum" or "noise," I can say that this is not so much a "distraction" as it is a sound that puts my amp temporarily out of commission. I plan on taking it to a amp shop and won't try messing with the electronics out of fear of damage to both myself and the amp (for those who would warn me otherwise). However, I was hoping that someone could give me an idea what the issue is, if for no other reason than just my wanting to know how much the repair work might cost me. I'd think the tubes would be the first thing to break in this case, but with a guitar plugged in, I can still hear my playing; still the sound of the guitar pales in comparison to the high-pitched mess I've had the misfortune of creating.

Help Please. Suggestions, Ideas, comments: all is appreciated by this amp novice.

Best,

Ty

[Regis]

Swap the 12AX7 for another one and see what happens.

[gibson05]

Thanks for replying!
So, I'm inferring that broken/damaged tubes can create excess noise? I was always under the impression that tubes, when broken, simply didn't function and dampened the volume. I live about an hour away from any place that works on amps unfortunately, which is partly why I'm asking here before trying what might seem like an obvious fix. Any idea what labor-related costs for replacing tubes generally are (tube prices aside)?

Ty

[JHow]

...Any idea what labor-related costs for replacing tubes generally are (tube prices aside)?...

In the old days regular people used to go to the drugstore and test and replace their own tubes.

Not to make light of your situation, but tubes are made to be replaced, they pull out of the sockets with finger-strength. If you just want to check quickly if a tube swap will help, it's not hard to do.

[Regis]

You probably jarred something in one of the tubes and it has become badly microphonic. It's possible it is one of the power tubes but I would start with the preamp 12AX7 then the phase inverter 12AX7. 12AX7's usually go for around $10-15. Bench charges probably would be around $50-$75.

Swapping the tube is simplicity, you pull the tube and insert the new one after lining up the pins.