Ebay Class A/B Push-Pull Amp Kit

I picked up the kit off of Ebay that had talked about in the Aliexpress tube amp kit thread. I went with the one labeled “HiFi Vacuum Tube Amplifier Class AB Push-pull Stereo Audio Amp DIY Kit/Assembled”. I put it together over Christmas break, but did not have much time to post or really listen to it much. It went together well, but I did have 2 issues. The first was oscillation. I had the output transformers hooked up incorrectly there was a label for P1 and P2 on the board. I had to reverse them. Next, I had one channel that was weak, and found a loose ground that had come undone and was contacting the 8ohm output tap. Easy fix. I also replace the RCA inputs with some that were more robust. I have been listening to it, and it really does sound quite good. It did seem a bit hissy up top. I had bought some Russian tubes that I show in a pic below and swapped those in. They got rid of the hissy top end, and sound a bit more composed. Overall, I am super happy with it. I am driving it with my Krell integrated set up as a preamp right now.

5 Likes

Here are a couple of pics of my amp. It is driving my latest towers, and doing it quite well.

8 Likes

My nest step is to build the a preamp with some modifications. I would like to use the “HiFi Vacuum Tube Preamp Home Stereo Audio Buffer Pre-Amplifier DIY Kit” I would then like to use a remote control volume and input selector. I found one that looks like it would work well, but I will need to modify the chassis to make it fit.

1 Like

That looks great! Glad you are happy with how it sounds.

Love the amp. Also love the TOOL vinyl in the wall!

1 Like

I am looking forward to see what yours looks like when you are done. I would love to get to the point of designing my own. I did some amplifier design work when I was in college for electrical engineering, but never enough to get good at it. This was enough to start fueling some interest.

Think I found the schematic:

1 Like

Yes, that is the one.