Power supply for condenser microphone tube buffer amp

I finally got all the parts is parts put together for my DIY power supply design:
 






 
 

Wow, very clean build. I recognize the Edcor transformer and the supply layout looks very much like a guitar amp supply. That's a huge amount of filtering. I really like the chassis. What are the specs Mike?

Awesome! I want one!

This is so cool Mike. I can't wait for the mic build.

 From what I understand the active stage in a condenser mic doesn't have a lot of gain. The primary role is to provide an impedance converter for the very high impedance of the capsule so that you don't have a drastic voltage drop when the mic sees the actual preamp. 
 
 Most tube tube mics use a single stage. The tubes used vary. It is common to either use a pentode, or one half of a dual stage triode. A very few modern tube circuits use two stages in an effort to reduce the noise floor, but many people react to that idea with concern that the resulting sound differs from the traditional tube character. These newer circuits either use two pentodes or both sides of a dual stage triode.
 
 Tubes that have been used by the traditional designs include the EF86 pentode and the 6072 dual triode.
 
 The Germans famously used the VF14 steel case pentode in the U47 mic but that tube hasn't been built since circa 1960. There is a German tube known as the AC701 that is said to be the only tube ever developed exclusively for a condenser microphone. It has the ideal impedance for a circuit mated to a condenser capsule. That tube isn't made any more.  The traditional German VF14 and AC701 tubes are very expensive these days so they are mainly used by people trying to keep high priced antique mics at factory spec.
 
 Contemporary traditional designs employ 6072, (12aY7), 12AT7, and 12AX7 dual triodes. A popular tube is the mini 5840 pentode. There are many nine pin pentodes used; EF86, EF800, EF802, EF804, and the E80F. Some of those pentodes were designed as RF tubes but they work good in the audio range too.
 
 I have collected a stash of the pentodes to add to the triodes I already had. The tubes I will focus on are the 6072, 5840, and E80F.
 

Very cool. I love the EF86 but there's only 1 brand the I use all the time. I have access to the E80F that was made by Phillips but haven't tried it yet. One thing I've learned is that pentodes have much less noise issues when they are run at low plate and screen voltages. My guitar amps typically have 100 volts on the plate and 90 volts on the screen grid. The huge gain that a pentode gives makes up for starving it for voltage.
 
I think I better gear up for some show and tell if I want to hang out here. Great work Mike.