Orange Amplification AD15/12 by prontold
The path I took to buying this amp was a strange and neurotic one, though I can't say I'm sorry for treading it. Essentially I went through a huge Pavement kick a couple of years ago and concurrently became obsessed with getting diverse guitar tones that I liked. One day, I payed extra attention to the intro riffs on the song "Old to Begin" off the so-so album Brighten the Corners, and heard this beautiful shimmering guitar tone. It wasn't distorted in an obvious way, but it was a little more beautiful than any pristine reproduction could be. I found out that Steven Malkmus was using an orange amp, started watching Youtube videos and researching my options, and last fall wound up purchasing this little dealie for a not bad price.
AD15s are discontinued, but can still be found occasionally for 500-800 dollars. They strike a good balance between having some serious tone at a respectable gig volume, and having some serious tone at a home-studio volume.
The amp is a little dark, but the harmonic overtones that the drive adds once you start heading into breakup territory are absolutely gorgeous. My favorite region for tone is with the preamp gain around 1:00-2:00, which lets the clean notes come through unmolested if you pick lightly, but lets you get some very gratifying saturation with a harder attack or bigger chords. This thing can do respectable cleans and good overdrive as well, though it can't get into full-on distortion without some help (granted I use fairly low output guitars, Jazzmaster or lipstick pickups). It seems to take pedals pretty well, although the absence of an effects loop means that you might have to do some careful balancing with overdriving the preamp and using dynamic effects like envelope filters or accumulating delay echoes.
Ease of Use
Good sounds are not too hard to come by with this unit. It's portable and light as well.
You get preamp gain, bass, mid, and treble eq frequencies (passive, I think), and a master volume. The EQ is not ultra-responsive, but some sculpting can be done if you get creative with how you cut bands relative to each other. A lot more sculpting can be done with mic positioning.
Notably absent, and somewhat missed, are any onboard reverb, an effects loop, external speaker outs (though you can still hook up the speaker connections to an external cab), and channel switching. I would like to have an effects loop, and reverb is always a nice option, but otherwise these omissions don't bother me.
Bang for Buck
I got this amp for about $500 including shipping. I'm sure there are better deals out there (some of the blackheart amps look really interesting), and more versatile ones, but this amp has a very unique sound that I wanted to add to my arsenal, and to achieve that at this price is, in my mind, a very worthwhile pursuit.