Gain of 6AK5

[Masami]

anyone know the gain of 6AK5 in triode and pentode mode?
can anyone provide a circuit of this tube to use as a voltage driver in the power amp?

Thanks.

[Tekko]

I have a schem i used for this tube, i found it on the net but i cannot remember if it was for 6AK5 or 6AU6.



I have typed wrong in the schem, supposed to be 6AK5W and not 6AK7W. This circuit worked very well for me with both the 6AU6 and 6AK5, but as i said i cannot remember for which tube it was for.

[Tekko]

Heres a schematic for 6AK5 i found today:



I hope this helps

[Tekko]

I have built this now to test it and the gain is about this: 11mV input to the 6AK5 gives about 500mV out.

[Sch3mat1c]

You should be able to get ample gain out of it. One 6CL6 stage I tested (which drew 20-30mA, plenty drive for anything) had a gain of 80. 6AU6 is listed for up to 400 or so gain, not much current though. 6AK5 can probably do 50-200 gain at 1-10mA, depending on what it looks like... I can do some graphing if you'd like.

Tim

[audiousername]

Have a look at the Mazda Belvu datasheet.

http://www.mif.pg.gda.pl/homepages/f...020/6/6AK5.pdf

Yes, it's in French, but the important parts are universally understood anyway. Pages two and three show lots of operating points and gives the gain and tension de sortie pour 5% de distortion harmonique totale for each... (output voltage at 5% THD)

[Masami]

Hi Tekko,

thank you for your reply and circuit.
what is the B+ you used in these circuits?

Hi Tim,

I want around 100 gain and 50Vrms output.
Any suggestion?

[Tekko]

The B+ is around 230-270v.

[Sch3mat1c]

Originally posted by Masami
I want around 100 gain and 50Vrms output.
Any suggestion?

How much supply voltage? Any particular screen voltage? Bias current?

At 5,000umhos transconductance, a 20kohm (or so) total load impedance will give gain = 100.

Tim