• 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.

Sofrito Line Amp

My first DIY project. I copied an existing working circuit from over at wtfamps.com. Thanks to diyAudio for the inspiration, help, and information.

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If you are interested in more build photo's, there is about ~100 progress shots on imgur
 
The 6L6 is used in the power supply as a feed forward shunt regulator.
Interesting, thanks. I wondered if the 6L6 was used that way. And this has no driver circuit, so you must have a preamp that provides adequate signal? I'll try to have a read through the link you provided.

Edit: Or perhaps not if this is a preamp, though I've never thought a 6V6 with it's swing requirements would serve as a driver per se. I'll have to read that thread as I'd think you'd need quite a big signal coming into this amp to make it work well. But maybe there's something I don't know going on here.

Edit 2: OK, read it. While the 6V6 wants more swing to take full advantage (particularly as an output tube), this amp utilizes just standard 1-2v output of lots of sources. Pretty constrained on the plate curves. I've never done this so am curious how it sounds.

Anyway, the amp looks quite nice!

Carl
 
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Edit 2: OK, read it. While the 6V6 wants more swing to take full advantage (particularly as an output tube), this amp utilizes just standard 1-2v output of lots of sources. Pretty constrained on the plate curves. I've never done this so am curious how it sounds.

Anyway, the amp looks quite nice!

Carl
Thanks for the compliment. The preamp sounds great to my ears, although, I don't have a huge amount of varied listening experiences with tube gear. I am running a phone pre(Black Cube) into this preamp, and then out into a Marantz PM8005 (power amp section). It is plenty loud at about 1/3 ish volume and sounds as clean and clear as the preamp section of the Marantz. There is definitely something extra pleasing to the sound, especially strong vocals.
 
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