• 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.

suggestions for a parallel feed 45 amp?

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Hi from Quebec!

I have a set of parallel feed outputs and chokes (Magnequest) that I got from a friend in a trade. Most schematics I find on the net do use transistors in the first stage.

I am looking simple and neat, direct coupled, parallel feed, no transistors anywhere. Just because I'm not confortable working with them anyway.

So, if someone has a link to suggest, a schematic, or a great idea. I'm opened to persuasion.

My first thought was to build an adaptation of the Shishido 2A3 (wich I built and loved) but for 45. But since I do own these parallel feed trannies, I guess I should give it a try.

Thanks!
 
Thanks for the suggestion, but that's exactly the design I had found.. and this one uses transistors.
Can Parallel Feed be built only with tubes ?

When it comes to building tube amps, I am a novice. Have built 3 of them.. they all worked, but I did follow the diagram, I admit. ;-) Then, I can do a few adjustments, but I'm no engineer. It's easier to tune pianos. ;-)
 
Thanks for the suggestion, but that's exactly the design I had found.. and this one uses transistors.
Can Parallel Feed be built only with tubes ?

When it comes to building tube amps, I am a novice. Have built 3 of them.. they all worked, but I did follow the diagram, I admit. ;-) Then, I can do a few adjustments, but I'm no engineer. It's easier to tune pianos. ;-)

It can you just need to use an inductor or resistor of the right value in place of the transistor shown in the link above.
 
You can't just sub in an inductor, the plate voltage on the driver will be messed up. A resistor will work, figure the current (I'm thinking it was 10ma, but didn't re-read the article, got stuck at the t-shirt ad). And the needed voltage drop (IIRC plate is 150v).
 
You can't just sub in an inductor, the plate voltage on the driver will be messed up. A resistor will work, figure the current (I'm thinking it was 10ma, but didn't re-read the article, got stuck at the t-shirt ad). And the needed voltage drop (IIRC plate is 150v).

Obviously you would add a CRC filter to drop the voltage then sub the ccs with an appropriate inductor. A resistor would be OK depending on how sensitive the speakers are (hiss.)
 
Here's another one:

I don't remember for sure but I think Gordan Rankin shared this design.
 

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