Sub-mini tube based pre amp

[mlabbee]

Here's the schematic for my latest project -

http://img.photobucket.com/albums/v514/mlabbee/Tube_Pre_Amp_Final.jpg

It's a two stage tube pre-amp using a 6021 tube with a Baxandall tone stack - roughly based on the Real McTube II with Adam's Amps Baxandall variation plugged in.  It sounds great on my breadboard, but I wanted to get some other eyes on this before I commit it to solder.  Any thoughts, suggestions?

I have two specific questions about doing tube builds:  First, my current layout has all the parts pretty close together - am I going to have noise issues with caps right next to the tube?  Second, a lot of tube pre-amp schematics I've seen have input and output jacks with a closed circuit - i.e., the tip is grounded until you plug in, breaking the tip to gournd circuit. Is there any particular reason for doing this?

[toneman]

looks workable.
i like all the tone controls.
that's a 6V regulator???
won't get 10V out.
did U want 12V 4 the filiments?
look @ the datasheet for a 7805 reg to turn it into a higherV.
and/or look @ datasheet for LM317 sdjustable reg.
think GEO has info on resistors used 2 set 2 various voltages.
I just did one for 9V and 12V for my MeatBall.
staytubed
tone

[mlabbee]

Thanks Toneman!

You should see the tone control on my breadboard. I didn't have all the right values for caps and resistors, so there are like 20 parts on the board - it looks ridiculous!  But it is an incredibly versatile tone stack - a really wide range of tones available.  I'm looking forward to getting all the right values and cleaning it up a bit.

The 6 volt regulator is fine - the 6021 tubes only require 6.3 volts on the heaters, not 12.

Anyone have any thoughts on these questions?

I have two specific questions about doing tube builds: First, my current layout has all the parts pretty close together - am I going to have noise issues with caps right next to the tube? Second, a lot of tube pre-amp schematics I've seen have input and output jacks with a closed circuit - i.e., the tip is grounded until you plug in, breaking the tip to gournd circuit. Is there any particular reason for doing this?

[ragtime8922]

Nice job! I didn't think you could put 400 volts on those tubes.

[mlabbee]

I'm just using 400V caps for overdesign/safety.  As it's shown, it should generate around 140 V.