6N1P for buffer instead of 6DJ8, 6922

[JojoD818]

Hello,

I'm a tube newbie, I would like to build a tube buffer as my first tube project. However, the 6N1P tube is the most easiest tube that can be found locally. Can I use the 6N1P in place of the 6922 or the 6DJ8 or the ECC88 or the 12AU7?

Can anyone also point me to a proven tube buffer schematic, hopefully with solid state psu?

Thanks in advance!
JojoD

[ErikdeBest]

Hi Jojo

As far as my little experience goes, 6N1P is pretty close to the 6DJ8, 6922 family. Heater current is far higher = 2A. Give a look at headwize

One of the editions of glassware shows a project of a "no gain, no pain" pre-amplifier using one 6922 tube/channel. Actually the circuit doesn´t even show an attenuator, so it´s a buffer already. Here is the link glass-ware Take care with the high voltages.

Good luck

Erik

[JojoD818]

Thank you very much! That was exactly what I was looking for. I am really seriously planning on building that circuit, hopefully to open my way on tubes and also to inject the "tube sound" to my solid state system.

However, the power supply does not give any values for the caps? Any suggested values? (I love this one, it uses descrete diodes! No extra cost for tube rectifiers )

Sincerely,
JojoD

[mcs]

The heater current is higher, but it is NOT 2A. It's 600mA according to the Svetlana datasheet.

There is a technote on the old Svetlana website showing circuits for the 6N1P here: http://www.svetlana.com/docs/TechBul...hnoteNo43.html

I have made gainstages based on circuit A, and that works very well.

Best regards,

Mikkel C. Simonsen

[ErikdeBest]

Hi JodoD818

I believe 200VDC rated caps must be sufficient for the PS, as the secondary from the trafo is 100VAC, what will give a raw 140VDC.

You could download the PS simulator from duncan amplifers and simulate the PS circuit. The program will calculate the voltage across each cap.

An other sugestion, although I haven´t tested it myself, is to add some more components around the bridge rectifier. Give a look at the power supply of the Thermionic Valve Analogue Stages for Digital Audio .
Van der veen uses something similar in the circuit of the maurits .

Good luck...and don´t invert the caps polarity,

Erik

[fdegrove]

Hi,

Just a quick note:

Don't rely on the data provided by the Svetlana site too much as it is partially in error.

They would have you believe it's a direct replacement for the 6DJ8 whereas it is not.

One major factor is that nominal Ri is closer to 11K another being the µ is 35, NOT 33.

This, of course will have an impact on Zo.

Cheers,

[mcs]

The Svetlana datasheets may be questionable, but the schematics shown in their technotes should work well. The ones I have tried do at least (including the one I pointed to).

Best regards,

Mikkel C. Simonsen

[Positron]

Fd, wondering if you have tried the 6n1ps and how did they sound?
The higher Ro and filament current, as you mentioned, is one reason I never considered them seriously. Did I overlook a good tube??

Thanks.

[fdegrove]

Hi,

Did I overlook a good tube??

That depends on your expectations...I wouldn't use it in a preamp as the last tube though.

BTW, you can call me by my first name: Frank.

I can tell endless stories about Russkie tubes as, as usual, most of them passed through Belgium prior to being exported to the US during the Cold War...

If ever I find myself in dire straights....I might take a shot at that and write a book about these gems.

Cheers,

[Positron]

Thanks for the info. Frank. Someone has suggested the 6n30, I believe. I am considering a new, more expensive model down the road to add to my collection, but I would have to do a total redesign, filament, plate etc.

How would you rate this tube?

Thanks for your advise.