I have no idea how to solder but I do have this pre amp and watching this is giving me confidence to perhaps give it a go assuming it sounds good post upgrade, I upgraded mine by replacing the valves for Tungsram nos as Steve Hoffman recommended me to and it sounds great

My kind of Upgrades...Very Nice!!!!  With the Cap leads, I like to use PTFE Clear Sleeving to protect against anything that may touch.

Great job!

I’m planning to buy an SLP90 soon, but there’s still one thing holding me back — the hum that seems to appear in some units. In your video, I noticed a short grounding wire under the PCB. Do you think that in some SLP90s it might be soldered badly, or maybe the black paint prevents it from making proper contact with the chassis?

Thanks for the really informative video. On mine, I’m also planning to add a steel shield between the transformers and the PCB, and twist the power supply wires.

I've recently purchased this preamplifer and I'm looking forward to upgrading the capacitors. I've already purchased the PSVAN ART TII Series 12AU7-S and it sounds wonderfull can I ask what sonic improvents the Mundorf caps made the preamplifer

Will you make a video when you upgrade the AE-1, I would like to upgrade mine but don't have much experience with electronics and I would love to see how you do it. mine has a slight hum also but I can live with that, I have the summit tubes arriving soon hopefully, customs did not make it easy lol and now the couriers are dragging their feet

So after all of this no mention of if it is a big improvement with the Mundorfs ?

What is all the part you used to be replaced the old one with the value and model thanks.

In your shop do you sell a kit of the upgrades for the SPL 90 clone? Also, how did it sound post upgrades? Was there a significant improvement in sound quality?

Can you share the schematic somewhere