• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Easy & Safe & Good sounding gainclone tube buffer

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I've just built this and i'm amazed at the sound. Sorry for the schematic, i would better have drawn it by hand, but i'm on a mac and have no capture software other than the awful McCad.

It is a millet-max tube stage with grid feedback. Sounds very, very good and runs on very, very low voltage. The tubeness is clearly audible but it has a much lower distortion than designs that use high voltage tubes operating on low voltage.

The sound is also much better than a cathode follower.

I use a separated power supply but using the same as the chipamp should work.

Advantages over common CF buffers:

· Better sound

· Safer operation (25V vs 60V)

· You don't need an extra transformer for the B+ (You do need it for the B+)

The heather psu should be referenced to ground unless you are trying to build a radio. The heather voltage should be the one of the tube you use (I use the 12AE6A). I set the bias at 18V but you can play with this at your will. If you use the ECC86 you will probably want to run it at a higher current, place a trimpot there and a small resistor to read the current if you are planning to play a lot with it.

Do you know the best of all? It took 15 minutes for me to get it working! I have to admit i was in a hurry but you can make it in less than an hour.

It's really worth listening to it.

Enjoy!
 

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