Scratch Build a Stereo Tube Amplifier Part 1 

Watching this video is like watching an electronics artist create a masterpiece. Truly an art form, thanks Tony for sharing your art with the world!

80 rectifier is like a 5Y3, not 5U4. Also, since those are directly heated types, they'll produce B+ before the rest of the amp is warmed up. An indirectly heated rectifier like a 6X5 or 5V4/GZ34 will warm up at the same rate. Also, you'd connect your filter cap to the cathode, not the anode (38:00 mark). Maximum input cap size (capacitance) can be found in most tube manuals. Voltage of the caps should be determined by the RMS voltage of the transformer x 1.414 for maximum voltage it should encounter, with operating voltage no more than 80% of rated. Despite the the few flubs I very much enjoyed this video!

Tubes are way over my head, but thanks to your fine explanation I may just begin to see some light in it.

Very useful information. Thank you!

Xraytonyb you are the best teacher on line.

Not boring... Excellent, Thanks...

Just found you, Part 1 looking good.

Getting ready to build my first tube amp. I bought a Dyanco VTA-ST120 KIT. And really would like to know what each part is and dose before building it. That way I have a full understanding of how the amp works. And would love to learn all I can about amp building. I find your videos of amp building very helpful. And would like to thank you for the videos.

Just a note in the Filter electros in the power supply, Solar inverters use lots of them rated 510V or higher and normally they all are very high quality, if you have service centers like for the brand Fronius you could ask them to go bin diving and you will get a truck load of free high quality capacitors :).

Fantastic material . Thank you so much for this very informative detailed video.

Very clear and informative, thanks for sharing all this!

Awesome explanations! Definitely thinking about making an amp like this one!

Excellent serious and I’m not easy to impress I’ve been playing guitar since I have been 14 I’m 70 now I’ve been working with two Banff starting at 14 I started learning tubes because that was all there was at the time been interesting time in electronics I happened to have been a qualified engineering tech that got misguided and got in the hi-fi happened to live close to what became a big audio store and lived my dream about working on extremely nice power abs and such Leamington Carver threshold nice but I got bored and I’ve tried different topologies of output tubes and circuitry I came up with a bridge style with four different devices and the output transformer across the two Centerpoint this allows for no DC bias current to be put through the transformer this allows the transformer trains states quicker and make for a superior frequency response a good square web out of a tube app is the holy grail

thank you so much xraytonyb. its very interesting and i cant wait to start making my very first stereo tube amp..

ANY amplifier that has 6BQ5's is a very clean sounding amplifier

if you ran the tube as a triode would it have similare desirable characteristics that the coveted big tube does?

Very informative, thank you :) Do you know where to get some plans for a basic stereo tube amp? I have a whole box of tubes and a soldering iron

Yeah it's from 2016 film and I write in 2017... Why don't just use standard wirewound power resistor. They are design to dissipate a lot of power/heat, have low self noise, and in standard wiring they are for all purposes coils. Also ferrite could be placed on it. And they might add a bit of safety as there're versions of wirewound resistors that work also as silent fuses.

Have to disagree with you on something- the plate and screen voltages may be the same in a lot of those amp configurations, but that is not the same as running the tube triode connected. The screen supply is taken on the B+ side of the transformer and the plate on the other. The resistance of the windings will not drop the voltage to the anode all that much so they have essentially the same voltage as measured with a meter.

Great Series concept... Looking forward to it! Is that old theater amp you have a Western Electric? Dollars to doughnuts; that's what it is... LOL!

Do you build and sell as well? 2-17-2021

I am trying to build my own 12au7 headphone amp but am not having much luck as it doesn't function correctly. I followed a schematic, would you be able to help me?

Hello! Just found your channel. Are you still doing business?

On a scale of 1 to Donald Trump, just how stupid would it be to use a switched mode supply on a tube amplifier? It would make the power supply a whole lot cheaper if you didn't need a great big transformer.