Three guesses as to what this is...

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I'm guessing that the power tube sockets will be chassis mounted anyway, with the smaller tubes poking through holes in the metal like on an Ampeg head, no?


EDIT: Doh! I just looked again and saw all those radials standing in the way ....

You know you can get those long-legged chassis mount octal sockets, right?

 
Can't comment on the new Tung Sols yet. Will report back after I've had a chance to monkey with this thing a little bit. I agree that the 6V6's take quite a bit of force to get into their sockets. I just put them in to take the picture.  Eventually there will be standoffs between the sockets and the board to help with the insertion force.  I'm well aware of the 6AQ5 and its similarity to the 6V6. I used 6V6's in this design because that's what the original has in it.

Same with the 5Y3.  I have a NOS original Sta-Level power transformer that will go in this unit so the 5V filament isn't a problem. This unit was built in part so I could find out what the difference in sound is between the 5Y3 and 1N4007's as rectifiers. I'll  keep your suggestion of the 6X4 in mind for later designs though.

Once I get the design finalized I'm considering offering a PC board to the group here, but it won't be this design.  After I find out what I need to know from this board I'll go through a complete redesign to eliminate the useless options and get the form factor down to something that will fit in a 2U or 3U case.  This board fits in a 6U case - not very space efficient but definitely impressive. This board would be a challenge even for an advanced DIY'er.

Joe


electrochronic said:
Joe ,

Looks like you used the New production Tung Sol there, I'm impressed with these for guitar amps, but have not used them
in recording gear. Can you comment on their usefulness.

Not surprising , The LA2A uses 6Aq5's which are also used as guitar output tubes , and cross over to 6V6 equiv.
Have you thought of using the 6Aq5's instead ? they are physically smaller ( 7 pin mini ), cheaper too.

Plugging a 6V6 into a tube socket mounted PCB looks like a delicate operation. Looks like it takes a little more force than
a normal PCB can withstand.

5Y3 is plentiful but requires a 5V transformer secondary , a dual 6X4 would fix that.

Just ramblin...... I'm sure that nothing really needs changing. Nice work.

Are you makin these available later ?

Still have to get a T4B going here to send out.

Build guitar amps much ?
 
My first guess is a variable mu compressor with a 6386 (?) and 7 pin sockets for a pair of triode wired 6BA6's or 6AU6's as an alternitave to the big $ tube.
Am I close?

Peace,
DrRick

joe-electro said:
Okay my fine DIY friends.  I've been working on this project for about 3 months now, and it's time to share with the group. Does anybody want to hazard a guess as to what this beast is?

Joe

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joe-electro said:
It was designed to be the ultimate Sta-Level prototyping platform. A beta prototype will follow soon after I determine which mods are beneficial and which aren't.

Hi Joe !
Did you find some time to play with your optional mods ? I am planning to build one with a pair of 6k4 as varimu tubes and a Collins 356B-1 output transfomer.
I would really like to hear about your findings on varimu input tubes (6BJ6, 6BA6,...) and your other mods if you had time to experiment.

Cheers !
 
Awesome work! I guessed right at post #1 but I missed the window.

I love the chassis. As a musician, if I walked into your studio, I'd say, "I don't know what that thing is, but I want my audio running through it."  :)
 
very cool joe!!
also interested in your findings of all the options you first mentioned since this one year journey started as an "ultimate" sta-level tweak / experiment.
best regards,
grant
 
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