Stout Reverb with Gain Pot

[dram56]

I am currently building a Stout Reverb Amp.  I do want the have control over the amount of Gain.  I see listed in the "Options" page, you can replace R14 470K resistor with a 500KA Pot.  That seems easy enough. 

There is also an option to use a DPDT Switch for Hot Gain or Lower Gain.  I got a little confused when looking at Doug's Stout build pics where he was using a DPDT Relay (which looked overly complicated for the task).  But in his current Stout Reverb PDF, on the "Options" page, it appears to be an ordinary DPDT switch. 

Which brings me to my question(s).
1. Is the Switch necessary when using the 500K Gain Pot?  Couldn't you simply dial back the Gain pot to change the gain from Hot to Lower Gain?
2. If the Switch does provide some other benefit, then could I use a mini DPDT toggle switch (see attached) to accomplish this task?
And one more question regarding the choice of the rectifier tube. 
The schematic specs a 5Y3 rectifier.  A typical 18 watt EL84 type amp would use an EZ81 rectifier.  I have used 5Y3 rectifiers in smaller wattage tube amps (like a champ), but have used GZ34s or 5AR4s in PR or DR amps.So, I was wondering if the little 5Y3 rectifier will be able to handle the load OK?  I am using the normal British 18 watt Power and Output transformers to run the compliment of 4 preamp tubes and 2 EL84s in this amp.
Thanks in advance for any advice.
Dave from Colorado

[sluckey]

You don't need the switch if you don't mind having the gain stage engaged all the time. The switch allows you to totally bypass the gain stage (a good feature IMO) and you can use a mini toggle. And you can replace R14 with a pot even if you don't have a switch (also a good idea). 5Y3 and EZ81 are both fine for this amp. Your choice.

[dram56]

Thanks Sluckey.
I will use my mini toggle & the 500k pot for gain control.


I will stick with the 5Y3 rectifier tube that Doug spec'ed.  Perhaps he was figuring that since there was already 4 pre-amp tubes and 2 el84 power tubes already on the 6.3v heater line, that maybe having the EZ81 on that same line might be a strain on that leg of the PT.  And since the 5Y3 uses the 5v 3a line, that might be better power distribution?  And if I should need any more out of the rectifier, there are plenty octal rectifier tubes to choose from.


Again, thanks for your help.