Just in time for Holy Week services, I upgraded my amp! I am currently playing through a Guytronix Ardmore head into an Avatar 1x12 cab. The Ardmore is a 7 watt, el84 amp with one 12AX7 in the preamp stage. I built it from a kit a couple years ago. It's a pretty cool, albeit simple, little amplifier. It has a single volume and tone and it takes my pedals really well.
The first change I made was with the preamp tube. I was using a sovtek 12AX7. I replaced it with a JJ 12AT7. This change effectively lowered the gain of the amp allowing me to get a little more clean out of it before it started breaking up.
The second change I made was to the speaker in the cabinet. I have been running a 15 watt Weber 12A100 Alnico for a couple years. It has a weird 2.8k spike in it that just wasn't working with the chimey nature of my amp. I replaced it with a 30 watt Weber Blue Dog Alnico. It really smoothed out the overall character of the sound. The sound guy at church noticed immediately. It sits in the mix better and isn't as annoying.