power supply for tube preamp

[rafafredd]

Hi.

I´m building a tube mic preamp and I would like to know your opinions about the power supply.

Should I use the original power supply rectified with 6X4 miniwatt tube or should I go with the alternate diode one?

What would be the best option?

 

[fdegrove]

TUBE MIC.

Hi,

IMO take the original one and if you can post a circuit we can even improve that.

You may not like what the diodes do and if you don't have a stiff PSU that's well isolated from the rest of the amplification circuit you're bound to hear it in the recording.

Just my 2 euronickels,

 

[B-Grade]

Tape OP?

Would this be the Mic pre in the tape op mag?

 

[rafafredd]

Here goes the original power supply

Note that this is not for a tube mic, but for a tube mic PREAMPLIFIER

Thanks

 

[rafafredd]

And the alternate one

Also would like to know if you can tell me the resistence for R6 and R11. I´m using 110V. I don´t know, but there´s a text file that says that this resistors depends on input voltage.

 

[fdegrove]

INVALID ATTACHMENT

Hi,

The .bmp file you posted doesn't seem to be valid.

Ciao,

I was too fast it would seem.

Works now so ignore my post.

Thanks,

 

[rafafredd]

look again

look again

 

[Joel]

What's wrong with the first one? Capacitance maybe a bit low, but other than that, looks ok.

 

[fdegrove]

PSU

Hi,

The tube PSU would certainly benefit from choke filtering and some good quality polypropylenes or PIOs behind it.

The SS one has an extra 48 VDC regulated but what is that for?
I can't see it in the tube PSU.

Cao.

 

[rafafredd]

PSU filter

Hi,

The tube PSU would certainly benefit from choke filtering and some good quality polypropylenes or PIOs behind it.


Cao.

Can you porvide more information on how to do it?

 

[rafafredd]

48v

The 48v is for phantom power supply.

 

[fdegrove]

CHOKE.

Hi,

Here is a link to a fellow members' PSU.

http://www.diyaudio.com/forums/showthread.php?s=&threadid=7066

The choke is where it says 5H/100mA and you can put it straight after the rectifier ( where you have this 1K5 5W resistor ) or you can put a small cap in front of it.
After that you can use your circuit as is.

The 48 V phantom supply you could do according to your second diagram.
The missing resistor to ground on the regulator will depend on the regulator type you use.

I have no idea about the powerconsuption of this supply but I suppose a standard LM317 should do the trick.

Ciao,