6N16B preamp

[Wavebourn]

There were many preamps discussed using 6SN7 and 6N1P. You may borrow ideas from them.

[artosalo]

All DIYers can not modify circuits using 6SN7, 6N1P, etc. to 6N16B.
Therefore I wanted to give an example.

[Wavebourn]

Originally Posted by artosalo

All DIYers can not modify circuits using 6SN7, 6N1P, etc. to 6N16B.
Therefore I wanted to give an example.

And you gave a good example. Add there Zen Mod's proposal, and it will be even better.

[artosalo]

Two FETs at the first anode as CCS ?

[Wavebourn]

Originally Posted by artosalo

Two FETs at the first anode as CCS ?

Yes, something like that. But I personally prefer a single FET with resistive degradation, connected like gyrator. However, any active load may contribute more noise than single resistor, but resulting distortions will be lower.

[artosalo]

Then the whole design must be changed since the size of anode resistor (together with resistors at the cathode) determines the gain, and I wanted to set it to some 10 dB. Line stage usually needs small gain.

In general I think that two FETs at the anode of medium or low mu triode is waisting of resources. Just one is sufficient. It usually represents some 500k to over 1M resistance. There is not much difference if this impedance is multiplied by 10 (even though some guys can clearly hear the difference).

[Wavebourn]

Sure, some guys can hear the difference when higher capacitance of more complex active load adds roll-off on highs.

[merlin el mago]

Originally Posted by artosalo

What are your requirements ?
- gain
- output impedance; low (cathode follower output) or higher (anode output)
- inverting or non-inverting construction
- low distortion or "tube sound" design

requirements:

-high gain
-low output impedance
-high input impedance
-non-inverting
-low distortion
-flat frecuency response

[Wavebourn]

The only concrete requirement is "Non-inverting", the rest is undefined. You have to put numbers for each criterion.

-high gain -- how much?
-low output impedance --lower than...?
-high input impedance --higher than...?
-non-inverting
-low distortion --what kind of distortions..., which level...?
-flat frecuency response --how many DB in which band?

[merlin el mago]

Originally Posted by Zen Mod

try like this

Rout in range of 4K4
presumed load around 100K
use Ub in range of 120-130V

expect around 95V at anode

pre-set CCS to 5mA (I'm lazy to read datasheet toi determine exact resistor )

float heater supply and lift it to 30-40V

best to heat with LM317 based CCS , preset to 400mA , when tube is hot , set exactly to 6V3

thanks for schematic:

input/output impedance?
gain?
if I don't use DN2450, how much current & voltage have to set my regulator?