Universal preamp with headphone
I made this as my first project to make the headphone output for the DENON CDP. But I decided to publish it as universal project for simpe to do preamp. Anybody can mount it in one afternoon.

This machine has three stages, all very simple.
The first is a typical SRPP lampizator , which goes out to the RCA. Thats all, all line level preamplifier.
For head-set which is more demanding in terms of current and power - there are two next stages. First - a triode amplifier with anode follower circuit, and second - a cathode follower buffer for 80 Ohm output impedance and high current.
In between the preamp and head section there is a headphone potentiometer.
If this is not inside a player but in separate box - the pot should be the first device after the input sockets, before the lampizator grid input.

I decided to use ecc88 tube which I like very much. But to go full throttle you may build a PRO version and use 6H6P tubes.

Of course there are simple improvements which anybody can add like a MKP bypass of all electrolytic capacitors and a coil (choke) in place of anode supply resistors of 1K. The chole should be good to deliver at least 20 mA each.
















Here is a small but excellent pre which I made in 2010


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