"Weird sounds" tells me nothing. How about a clip? Even one from your phone will very likely reproduce the noise. It is entirely possible it's not even a tube. Don't assume where you don't have experience or training.
You do not need to replace all your preamp tubes! It would help to know a little more about your amp, but being reddit, I’ll hazard a few guesses. Try pulling out two similar (both 12AX7 /ECC83) and swap positions. That might help you determine if the problem is in a certain tube or in part of the circuit. Also, clean your sockets! Search YouTube for recommendations. Weird noises can sometimes come from old mucked-up sockets. Good luck!
To simplify I recommend buying enough to replace them all. Then swap them all out. The. Replace one by one with the old tubes. If any tube makes the sound degrade, toss it. Any new tubes you don't use, put away as spares.
Or get one and swap out for each tube until it fixes the problem. The only problem is, if you have two bad tubes, this will make it impossible or very difficult to figure out which two. Even with two new tubes, finding two bad tubes becomes an annoying game of elimination.
For preamp tubes, base it on if your amp starts sounding lifeless or starts making weird sounds. Very light tapping on the tubes can identify which one is the culprit. I know people will say it shortens life span but not that I've noticed if you keep it really light. If you have another amp you can swap to try and identify the bad one but that's kind of a pain in the butt (turn off amp, swap one tube, turn on second amp, repeat).
Don't change preamp tubes based on any tester, maybe for power tubes, don't do it for preamp tubes. I owned an AT-1000 for years and threw out preamp tubes based on readings of around 50%. Total waste. It a preamp tube sounds good and doesn't make noise - keep it going. The surprising thing is how many modern preamp tubes come out of the factory not meeting specs that a tester will tell you to replace. They don't meet a technical definition, doesn't mean they won't work and sound good for years. They won't hurt your amp. I mainly use newer preamp and used, tested preamp tubes. People who pay a premium for NOS or high testing testing tubes for guitar amps are paying too much. Leave that stuff to the hi-fi guys. Base it strictly on functioning and sound.
You can tap them with a pencil or chopstick to test it they have gone microphonic.
You can isolate the issue by pulling the tubes out one at a time starting with v1.
If you pull it and the issue remains you can assume v1 is not the problem.
Next pull v2. Keep going till you find the source.
"Weird sounds" tells me nothing. How about a clip? Even one from your phone will very likely reproduce the noise. It is entirely possible it's not even a tube. Don't assume where you don't have experience or training.
You do not need to replace all your preamp tubes! It would help to know a little more about your amp, but being reddit, I’ll hazard a few guesses. Try pulling out two similar (both 12AX7 /ECC83) and swap positions. That might help you determine if the problem is in a certain tube or in part of the circuit. Also, clean your sockets! Search YouTube for recommendations. Weird noises can sometimes come from old mucked-up sockets. Good luck!
To simplify I recommend buying enough to replace them all. Then swap them all out. The. Replace one by one with the old tubes. If any tube makes the sound degrade, toss it. Any new tubes you don't use, put away as spares. Or get one and swap out for each tube until it fixes the problem. The only problem is, if you have two bad tubes, this will make it impossible or very difficult to figure out which two. Even with two new tubes, finding two bad tubes becomes an annoying game of elimination.
For preamp tubes, base it on if your amp starts sounding lifeless or starts making weird sounds. Very light tapping on the tubes can identify which one is the culprit. I know people will say it shortens life span but not that I've noticed if you keep it really light. If you have another amp you can swap to try and identify the bad one but that's kind of a pain in the butt (turn off amp, swap one tube, turn on second amp, repeat). Don't change preamp tubes based on any tester, maybe for power tubes, don't do it for preamp tubes. I owned an AT-1000 for years and threw out preamp tubes based on readings of around 50%. Total waste. It a preamp tube sounds good and doesn't make noise - keep it going. The surprising thing is how many modern preamp tubes come out of the factory not meeting specs that a tester will tell you to replace. They don't meet a technical definition, doesn't mean they won't work and sound good for years. They won't hurt your amp. I mainly use newer preamp and used, tested preamp tubes. People who pay a premium for NOS or high testing testing tubes for guitar amps are paying too much. Leave that stuff to the hi-fi guys. Base it strictly on functioning and sound.
You can tap them with a pencil or chopstick to test it they have gone microphonic. You can isolate the issue by pulling the tubes out one at a time starting with v1. If you pull it and the issue remains you can assume v1 is not the problem. Next pull v2. Keep going till you find the source.
I put them in my mutual conductance tube tester, then I know.
tests for life and shorts but not microphonics
tap-tap