There are tons of reviews about this amp and tons of forums telling people to mod this amp straight out of the box. I say DON'T. Don't touch it. There's a reason Vox build this lovely little powerhouse the way they did. Simply put - Engineering. These guys know what they are doing. They use certain components for a reason. They source the proper parts and custom make other part to make sure every thing is perfect. This amp sound totally VOX because of this. The custom VX10 sounds perfect in the mostly closed back cabinet. The Chinese made tube don't suck, like many purists think. They go well with the all circuit board construction. Even the way the chassis is engineered to fit perfectly in this small sized cabinet. Light, portable, loud, clean headroom and lots of room for grit. You can't touch an amp like this for the price. The closest size weight amp is the Fender Princeton (I own a 1966). A new Princeton will run double in price. OK, the Princeton is more handmade, but when you play these side by side, the Vox AC 10 C1 stands up and hold its own. It will be a classic amp some day, like the Princeton. Get in on the ground floor and pick one up for 499. That's nothing for what you get. Pure, Sweet, Jangly, Gritty, Real VOX Tone! Don't change a thing on this amp. You'll change the base character and be disappointed, as well as a few hundred euro poorer for having bought NOS tubes and vintage speaker. You don't need to do it. It's perfect as it is. VOX tone at its best.