Blackstar HT1 broke

[vitss]

Blackstar HT1 fell over and since then it gives only noise.
I replaced the tubes (7025 / 12AX7 and ECC82 / 12AU7) by Groove Tubes Gold Series GT-ECC83-S (12AX7A).
result is I get a little bit of guitar sound but further only noise.

anybody who can suggest what i can do next?

thanx a lot

[Mick Bailey]

Welcome to the forum.

The 12AU7 is the output driver tube and can't be replaced by a 12AX7 - it doesn't have the current handling. Have you tried keeping the replacement GT preamp tube, but reinstalling the original 12AU7? Check that both heaters are glowing inside the tube.

[km6xz]

One thing you could try to isolate the problem is use the headphone jack to see if the sound is normal in phones. If so, there is a good chance the speaker magnet shifted so the voice coil is binding producing weak output, mostly mid-range and above. If the headphones sound the same you have eliminated the speaker as the problem.
Did it fall forward or on its back. If forward look for a broken
Although you have replaced the tubes, Groove Tube are almost the least reliable on the market so news ones does not guarantee good tubes. GT is a marketing scam for high prices, and not up to the QC levels of other cheaper brands.
What test instruments to do have available?

[Jazz P Bass]

Agree. Which way did it fall.
How far?
If forward, was the cord plugged in?

[PeanutNore]

Like Mick pointed out, the problem here is definitely that you replaced the 12AU7 power tube with a 12AX7 which isn't able to provide the current required in an output stage. Since it was producing noise before, the original 12AU7 output tube is probably still ok, but the preamp tube was damaged. Try putting the original 12AU7 back. Otherwise, get a direct replacement. JJ makes a very tough 12AU7 that worked well in my HT1.

[vitss]

thanks for the replys. it seems the print was broken.
fixed.
greets

[gui_tarzan]

GT is a marketing scam for high prices, and not up to the QC levels of other cheaper brands.

Sort of like Microsoft.