• 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.

I need help for amps.

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Hi everyone!
I'm new here and I think the forum is really good. I made two guitar amps, 1 and 5 W. Now I made a HI-end amplifier from a few watts. And now that I need you. Which amplifier? 6c33 or 300B or simply with EL84 (with them I have the experience). Amplifier may not be top.
(We say in Croatia: "The first kittens are thrown into the water" <= this is a joke.)
Maybe something with ECC82 + EL84 or similar? The forum is a lot of schemes. Let's extract that to me. :wave2:
Thank you very much.
Dean
 
This depends on what you are trying to do. I assume you want a slow journey up the power scale, so your 1 and 5 W amplifiers could be a prelude to an 8 W unit using a pair of 6BQ5 tubes.

There are so many circuits to build it's hard to advise you. It will depend on what parts you have available.

I prefer solid state and am in the process of building an amplifier with the LM4780. This unit, barely 2 cm square, can deliver 120 W of audio. I don't plan on making a unit that powerful. I recently built one with about 25 W, also solid state.

My philosophy is to build amplifiers without distortion. I don't care for the sound of amplifier distortion, even with guitars. I prefer the clean smooth sound of players like Charlie Christian and Les Paul and Barney Kessel. Definitely jazz oriented, not rock.
 
So a push pull tube amplifier for 10W? You can use 6BQ5's as an example. You will need an output transformer and a power supply and a driver stage. If you want volume, bass, and treble controls you will need a stage for that. The driver can be a 12AU7 and the tone amplifier a 12AX7.

Figure maybe 300 Volts for the output stage. Look in the tube manual to find the proper bias, then create that either with a bias supply or cathode resistor.

Of course you will need to do all this twice (except the power supply) for stereo.

Rather than trying to design every component value, you can take a short cut by searching for existing amplifiers using similar tubes and copy the schematic diagrams with minor changes to suit yourself.

Another short cut would be to find an old unit and rebuild it to your own desires.
 
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