Finally got the parcel with the new valves in it home from the post office, since my Marshall amp is at uni, I will be taking the parcel with me when I go to uni, along with my laptop computer, Scarlett 2i2 Audio Interface, and etc so I can do the before/after demo recordings, I do need to stop off at Battery world to get them to order in a new rechargeable battery for my laptop computer though, but it can still be powered by the power adapter, once everything is sorted I'll post a link to the before/after demo recording so stay tuned.