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Tube Rectifier: What and How?

Just ordered my SSE PCB, and I'm filling online carts with parts now. I've come to the FRED diodes, and in my research trying to figure out what the heck a FRED is, I see that there's also the option to use a tube rectifier.
Well I'm a total NOOB, and I don't know really know what a tube rectifier is. But I get the impression it's better than the solid state options.
Is that correct? Is a tube rectifier the way to go?
If so, how do I implement it? What do I need to buy for it? Where does it go?
Should I just stick with solid state? If so, what's the current DigiKey part number for those FRED thingies?
I'm floundering here, people. I need a life preserver. Any help would be most appreciated.
 
Is this your first build and first entry into high voltage? If so, my recommendation is to stick with the plan, almost like baking or cooking something for the first time. when in doubt follow the 'recipe', measure, tinker, read to understand, ask questions, then make adjustments. Follow TubeLab's instructions...build a working amp, learn whilst doing, then try deviations.

WARNING - electricity hurts and has the potential to cause death. As one of my old electrical instructors used to yell 'Its not the volts that will killya, its dem amps'.

George's website on build is key, read it a few times, read the installation guide, etc. then get all of the bits and bobs ready. Then start to solder! get it plugged up and listen! if you decide that a rectifier valve will change the sound, check the installed parts, verify that the valve selected is 'plug in and play'. then try it out.

diodes are the modern version of vacuum tube (valve) rectifiers and provide glow as well as 'rectifying' current. Some are even mesmerizing, like the 866a or any of the Xenon variants. The purpose of the diode is to provide consistent current needed by other parts within the circuit. Modern diodes are supposed to be more stabile than valves, sometimes that is true, sometimes the opposite is true. I guess it really depends on QA

AS to 'better' - that is a personal thing. A well designed amplifier is simply well designed. If what you are attempting to create is only possible through modern diodes, then that is the path you must walk. If the path has choices...then do not get bogged down, you will be happy with either choice. And when you are no longer happy with that choice...change...wash, rinse, repeat. Welcome to the world of DIY Audio!
 
The SSE board has the tube rectifier circuit built in. That is the function of the 5AR4 tube. Nothing special needs to be done to make it work as it is the default option.

The FRED diodes allow for a solid state rectifier option. They can be left out of the build completely if the solid state option is not desired as they do nothing if the rectifier switch is not installed. Most builders do not use them.

There are 3 components on the board that are not shown on all parts list, D3, D4 and TR1. They were added to extend the life of the rectifier tube. D3 and D4 are 1N4007 or UF4007 diodes and TR1 is a CL140 inrush current limiter. Make sure that you order them when you get parts, and the board will not work without them.
 
Is this your first build and first entry into high voltage? If so, my recommendation is to stick with the plan, almost like baking or cooking something for the first time. when in doubt follow the 'recipe', measure, tinker, read to understand, ask questions, then make adjustments. Follow TubeLab's instructions...build a working amp, learn whilst doing, then try deviations.

WARNING - electricity hurts and has the potential to cause death. As one of my old electrical instructors used to yell 'Its not the volts that will killya, its dem amps'.

George's website on build is key, read it a few times, read the installation guide, etc. then get all of the bits and bobs ready. Then start to solder! get it plugged up and listen! if you decide that a rectifier valve will change the sound, check the installed parts, verify that the valve selected is 'plug in and play'. then try it out.

diodes are the modern version of vacuum tube (valve) rectifiers and provide glow as well as 'rectifying' current. Some are even mesmerizing, like the 866a or any of the Xenon variants. The purpose of the diode is to provide consistent current needed by other parts within the circuit. Modern diodes are supposed to be more stabile than valves, sometimes that is true, sometimes the opposite is true. I guess it really depends on QA

AS to 'better' - that is a personal thing. A well designed amplifier is simply well designed. If what you are attempting to create is only possible through modern diodes, then that is the path you must walk. If the path has choices...then do not get bogged down, you will be happy with either choice. And when you are no longer happy with that choice...change...wash, rinse, repeat. Welcome to the world of DIY Audio!

Thanks for this very helpful and eloquent response! I fully appreciate your recipe analogy.
This won't be my first tube amp build- I built the Bottlehead Crack last year. But this is a different type of build. SSE seems to require a more studious approach, compared to the Bottlehead Crack which was basically Audio Lego.
 
The SSE board has the tube rectifier circuit built in. That is the function of the 5AR4 tube. Nothing special needs to be done to make it work as it is the default option.

The FRED diodes allow for a solid state rectifier option. They can be left out of the build completely if the solid state option is not desired as they do nothing if the rectifier switch is not installed. Most builders do not use them.

There are 3 components on the board that are not shown on all parts list, D3, D4 and TR1. They were added to extend the life of the rectifier tube. D3 and D4 are 1N4007 or UF4007 diodes and TR1 is a CL140 inrush current limiter. Make sure that you order them when you get parts, and the board will not work without them.

A response from the man himself! Thanks so much for chiming in!
Sounds very straightforward. I definitely prefer the tube rectifier option- because hey, if I'm gonna build a tube amp, it should have as many tubes as possible! But I did already order those FRED diodes, so perhaps I'll put that switch in just for kicks. Or just save those diodes for a future project. You never know when you'll need a diode.

Say, since I've got your ear for a second, let me ask another question that's been on my mind. I purchased a "Motor Run" capacitor (this one), since that seemed to be a worthwhile upgrade. But it doesn't have any kind of mounting bracket, so I'm wondering what's the best way to ground the metal exterior of the capacitor to the top plate of the amp? Is that grounding even necessary?
 
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The can should be grounded if it is exposed where it can be touched. It is possible for a voltage to appear on the can due to leakage currents making for a possible shocking experience.

I have the same cap in my SSE. I mounted it using a clamp intended for a "computer grade" electrolytic can cap. I pulled out of something I was taking apart, so I don't know where it originally came from.
 
That looks like the clamp in my amp.
 

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