True, however at the bottom cover there are two slim 120x15 fans pushing air into the chassis and helping with venting air around tubes thru vent holes. Thanks to this, its just warm to the touch. Without that, it would break probably and also top cover over tubes would be dangerously hot. I can switch two speeds for summer/winter mode 
WOW! If that’s the going price, I’m rich!
I have several MV tubes. These 866JRs are extra cool because they function pretty much the same as the 866A, but without the to cap!
About half year. I am quite experienced in tube amps so thankfuly no issues at all
its super simple schematic with low amount of negative feedback and gain so there is nothing that should create issues. I must admit I was a bit afraid of very low gridstoppers value at output tubes. As I wanted AB2 triode mode, big values would degrade driver current dramatically, however no gridstopper and I would have oscilation issues, maybe. Havent tested it without, but I've used compromise of 100R resistors there - low enough to not limit drive current but at least something to create HP filter. PCB is very useful indeed when doing current sources and lot of trims for bias etc... also helps a lot to guide tube sockets more precise for chassis openings and makes build simpler in many ways.
If you are more interested, you can read whole build article in blog post linked below, just use google translator to translate from slovak to english:
Vacuum Tube Power Amplifier - VA Tube Amp
About half year. I am quite experienced in tube amps so thankfuly no issues at all
PCB is very useful indeed when doing current sources and lot of trims for bias etc... also helps a lot to guide tube sockets more precise for chassis openings and makes build simpler in many ways.
If you are more interested, you can read whole build article in blog post linked below, just use google translator to translate from slovak to english:
Vacuum Tube Power Amplifier - VA Tube Amp
Very professional indeed. Great build.
1989? Whoa, I was 3 back then, the Berlin wall was destroyed, and Poland had its first free elections ending the old communist misgovernment. That was a loooooong time ago
This is a clean and absolutely beautiful build, I have to say. Brings the tears of joy to my eyes. I wonder how it looked like when originally built. The power socket, components, transformers etc.
This is a clean and absolutely beautiful build, I have to say. Brings the tears of joy to my eyes. I wonder how it looked like when originally built. The power socket, components, transformers etc.
hello this is a DIY build, we made 2 amplifier with a friends, chassis is in aluminum
1 6080 for both channel monotriode, 1 ECC 83 per channel, 1 GZ32 as rectifier
transformer and self are from Millerioux France
total power is around 3watts per channel , the level is incredible .
You may see with new condensator , the original work well from 1989 to 2019 but become dry and outside of spec , tubes are from 89 except one ECC 83.
i have spare of tube
remaining resistor has been tested and good .
sound is excellent
1 6080 for both channel monotriode, 1 ECC 83 per channel, 1 GZ32 as rectifier
transformer and self are from Millerioux France
total power is around 3watts per channel , the level is incredible .
You may see with new condensator , the original work well from 1989 to 2019 but become dry and outside of spec , tubes are from 89 except one ECC 83.
i have spare of tube
remaining resistor has been tested and good .
sound is excellent
That's cool
- a three-tube amp, though with SS rectifier you could have made a 2-tube amp.I went for somwthing similar using an ECC81 (I think) as driver but the 5998A dual triode, which has higher gain and is easier to drive. But I've tested my amp with 6AS7G and it works perfect too.
