Stereo Integrated Tube Amplifier DIY Kit

This was a great first, serious project to take on. I bought a nice hammond chassis, mounted the board inside with the tubes and transformers visible outside, and added a selector switch. I'm using it for home theater. Nice nice sound. Note of warning: Don't follow the directions - they tell you to ground the potentiometer to the circuit board - which kills one audio channel.

Nice amp, sounds very good. I'd call this an intermediate build, the instructions are good, all the bits are included, but you'd want a bit of electronic background or have a friend with some. This is an older kit, but the tubes are available online as NOS, so if you decide to try it, buy a spare set of tubes at the same time. Tube amps are fun, they sound nice, they glow, everyone wants to talk about them when they see one...

very happy

8 watts output ?? Vacuum tubes are valued for their power while maintaining its unique sound before clipping. How bout something w/ 2 pair of 6v6's? ;-0

I purchased a virtually identical (earlier) model of this amp 12 years ago. It has served me so amazingly well since then. A couple of years ago, I had a capacitor go out, so decided to spend $20 on a handful of upgraded components. It took an amazing amp and made it even better! I recommend doing some mods if you like to tinker with things, but by no means is it required or even necessary. It just helps the neurotic of us--who like to further enhance bang for buck ratio--happier. You can't go wrong here, with an entry level tube amp that you get to build yourself. Antique Electronics Supply (AES) is an amazing company, who has been incredibly helpful the few times I've contacted them. Heck, if you're on the fence, call them up! They aren't just uninformed salespeople--they can answer any questions you have, technical or otherwise! Please read the numerous comments of the 1-star reviews, as well. You'll quickly see they are ill-founded. (Besides them just being factually incorrect, you'll also notice none of them actually purchased the amp!)

• As an introduction to that relaxing, tube sound, this is a great first amp. It sounds very good. • As a first tube amp kit, this is a great kit. It is easy to build. One great thing about this rather bare-bones tube amp kit though is that there are so many ways you can modify it and improve the sound and quality of the amp. • You can of course try swapping tubes from different manufacturers. Or trying to find matched/balanced tubes. Keep in mind though that these tubes are no longer made and so you're going to have to look online for used tubes. • Many "tweakers" go straight for higher quality capacitors, especially the so-called "coupling capacitors". For a little extra money you can find more exotic capacitors and replace the ones supplied with the kit. • Replace the poor power switch. • The output transformers are adequate but more expensive output transformers can do wonders to carry more of the low end of your sound. With that said however, know that tube amps notoriously underperform with low-frequencies. If you like a lot of bass in your music you'll probably want to pair this amp with a powered subwoofer. Here are a couple of caveats, however. • It leaves high voltages exposed. You can remedy this by building it inside of some sort of enclosure. (Search the web for "k12 tube amp" to see what others have done.) • It gets hot. Such is the case for any tube amp of any significant wattage though. If you build a chassis (see above) and leave the tubes exposed, a metal cage can protect you from the hot tubes. If you don't have kids or keep it on a high enough shelf, you should be okay to just remember not to touch the tubes. • The power switch is pretty poor. Given all the above, this is a great place to start. Perhaps, like me, you'll find that years later you're deeper and deeper into vacuum tube amplifiers. This was my first and now, years later, I've perhaps built thirty or more various vacuum tube amplifiers.

I built one of these like 10 years ago that I purchased from AES (Antique Electronic Supply). They had some early business ties with S5 (I think the designer worked at AES and then went to or started S5). It's the predecessor of the S5's K-12G kit, but this one actually uses better sounding tubes IMO. I have not heard S5's even newer K-8LS, but I don't think you can go wrong with either S5 or this AES kit. I have built, owned, sold, and bought several tube amps, some with a multi-thousand dollar price tag and have to say this little guy does sound great, and can be made even better with some minor modification. It has a very warm/sweet signature, but without giving up clarity. Down sides: 1) hum/buzz level is kind of high 2) don't connect the potentiometer ground where it says to (this was pointed out in another review). 3) I also seem to recall that the polarity markings on the PCB for one of the capacitors is backwards (use a meter to verify negative cap terminals are connected to ground before powering on).