Thermionic valves, vacuum tubes, lamps or whatever they are called were you live are as fashionable in audio equipment today as rows of blinking led's were in the early 80's, and partly for the same reason, both shine rather nicely esp. if you turn down the lights.
Acoustic Masterpiece Makes the 11 watt M-101, it's a power amp with attenuators so you can run it without a pre-amp if needed. .
The Affordable Valve Company While their products aren't exactly outrageously expensive, their definition of "affordable" is not quite the same as mine. Nice amps nevertheless.
Air Tight This is the new company run by the former head of Luxman, their range of valve based power amps has been getting a lot of attention lately in particular the KT-88 based ATM-2 but the more recent ATM-300 that's based on the ever so popular 300B in a single ended configuration has also been raising some eyebrows, but the most technically interesting (and the most expensive) model from the company is the ATM-3 monoblock, it allows you to switch from a 55W triode operation to a ultra linear mode that gives you 110 watts, neat. We have not been able to find a homepage for the company but you can find more information on their power amps here and their preamps here.
Alouette Audio Has an interesting true class A hybrid amp available that's called A50, it's a dual mono unit internally and you can read the technical specs here, one of the odder looking amps around (and that's not in a negative sense).
Antique Sound Laboratory Best for their range of budget hi-fi, their integrated and power amplifiers in particular are some of the cheapest on the market, if not the cheapest in fact, but the company actually make a large range of amplifiers with various topologies including some high end models.
Aronov Audio Makes a high end valve integrated amplifier, the company does not have a homepage but you can read a review of the Aronov LA-200 by AudioBeat from 2011, for starters, otherwise the only way to get more info is to visit the company in Los Angeles, CA, USA.
Art Audio Has a large range of valve amps, mostly single ended power amplifiers but also a couple of push pull units and preamps, the only model they have any info on the web is the Carissa, a single ended triode amp that gives out a rather impressive 16w (all things considered).
Audio Experience Has a few fairly keenly priced amps along with a couple of real high end products, their best known model is probably The Music Mk3 preamplifier but under the YS-Audio brand there were probably thousand of the earlier Mk2 incarnation sold on ebay and other internet sites. Next up is the Symphones preamplifier which features 12AX7A valves in the amplification stage and unusually enough for an amplifiers in this price range both of the above feature a valve rectified power supply, there is also available a more refined version of the Symphonies amplifier in the form of the Symphonies Plus that features a dual Mono configuration. YSA 100 which is a 120W rated monoblock push pull design that is based around the KT-90. Their top of the line model is the U300B but that is a single ended monoblock based around the venerable 300B SE and is rated at 10W. See also Audio Experience RIAA Preamplifiers.
Audion Makes a well regarded range of amps, including a 300B based single ended design and the Sterling 2x9w integrated amplifier that despite appearances will drive quite difficult loads.
Audio Note/Kondo Makes some of the most revered amplifiers in the business, the company is run by Kondo-San, a noted perfectionist that single handily started the "silver mania" in the 70's when he began winding output transformers out of silver for use in valve amps, his obsession with getting things right has meant that the company manufactures their amplifiers from scratch, almost all the components in their amplifiers except the valves themselves are made in-house and this has lead to some of their products having price tags that almost beggar belief. The company is best known for their single ended designs such as the Neiro 2000 stereo power amp that has 2A3's in a parallel configuration, but they recently introduced the X-60 monoblocks that have 300B's in a push pull configuration.
Audio Power Manufacrures a large range of valve based amplifiers.
Audio Research Well loved manufacturer of (mostly) valve based audio, their reference series is perhaps the best known, it consists of the Reference 600 MkIII and the Reference 300 MkII power amps along with a line of preamplifiers, phono preamp etc.. The company also has a line of more reasonably priced valve products including the LS25 MkII preamp and the VT 100 MkIII power amp.
Audio Tekne The company makes a number of all-valve transformer coupled amplifiers, these are all low-power to very low power designs but not as most people seem to believe SET topologies powered but rather triode based push-pull designs.
Audio Valve Well the name say's it all does it not ? High quality German valve amps, their main claim to fame is the computer controlled biasing that eliminates the need for matched valves.
Ayon Audio Has a line of single ended triode power amps with zero feedback topology, the 300b offers 2x20w into 8 ohms, the Sunrise offers 2x25, these are both integrated models and have 3 line inputs plus a direct valve input, the Sunrise also features a remote control. The company also has the Reference monoblock that uses parallelisation to get 55w >8ohm output power and the more conventional Classic monoblock that gives you 30w >8ohms. More info here.