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Firstly, thanks to all for your comments on my inaugural post of me and Maynard's Little Gem. If I missed answering some of you that's on me. Your comments are all appreciated. What is "THE 99%" ? Recently, while showing one of my tube amp builds to my sister, I noticed her eyes glazing over. WHAT!?, NOT INTERESTING?! (I asked) Yup, I found from talking to her that not only did she not know what she was looking at, she really wasn't interested in finding out either.... She's a great gal but,,, REALLY? =/ I then realized that she as well as hoards of disinterested others, make up about 99% of the population. That's a lot of potential converts but as Cartman said in Southpark "How do I reach these kids?!" Since the merits of tubes amps alone aren't enough to impact the 99%. I figured I'd make one that would compel them to take notice and maybe even ask a question or two about it. (Check and Mate!) Enter, the P.T. Barn-Amp. It's as much a spectacle as it is an amp, The 5 channel light show is from XKITZ and is the main feature but I put in some stuff for us 1%'rs too, such as: Through chassis forced air cooling. The chassis holes for the 11BM8's are over-sized and air is forced past them from below. This air flow also cools the interior of the case. Auto soft-start. Upon power up, the orange light illuminates to show the soft-start circuit has engaged.. 15 seconds later, the orange light goes out and the blue one goes on to indicate full heater voltage is being applied. DC power supply for the filaments. Speaks for itself... Overheat indicator Shouldn't ever need it but I had some holes to fill... See below. The chassis is from an old piece of medical test gear. As such, it came with a pretty sweet ac input module with all kinds of filtering and de-spiking, which I left in and put to good use. The amp circuit itself is the popular George Fathauer kit that uses (4) 11BM8's. While I wanted to use a Maynard design, I had a lot to put in the case that wasn't amp, so I chose this one for it's compact footprint. Happily, I also found it to be quite listenable with lots of volume. My only two notes are that there is a small bit of background hum that's not affected by the volume control; small enough, that I haven't even bothered to look for it yet and the bass rolls off sooner than you'd expect it to. The former may just be B+ ripple and the later is probably due to the modest OT's that come in the kit. A number of on-line chats seem to support that notion. No worries though because an equalizer and two Klipsch RB-61's make it sound tasty. As expected, the 0A3's put on a great show in subdued lighting and they even show up in daytime. What I didn't see coming is that even though the 0A3's are from the same batch, they can differ noticeably in the amount of light they put out. What you see in the You-Tube is the best matching I could do with the 0A3's I had on hand. I prefer to use the amp with the Coke bottle gas regulators because,,, COKE BOTTLE GAS REGULATORS!,,, but I am considering retrofitting some 40W Edison bulbs with octal plug bases for insertion directly into the 0A3 sockets. That should satisfy anyone's brightness needs. Lastly, you'll notice some empty real-estate to the right of the light show controls. That area was planned to host VU meters but I ended up needing that space for the light show cpu board, plus as the amp came together, meters seemed superfluous. I guarantee you don't even notice it when this thing gets cranking. Maybe a nice logo could go there. Maybe not... Anyway, that's it. Show it to some 99%'rs and let me know what they say... Next up: A pedigreed Maynard design with built in real time diagnostics, status and waveform monitoring. To be dubbed; The Tech Amp (a Winter project so it'll be a while.) Thanks for looking and have a great Fall y'all, Stu