1st full tube amp Oldchen EL34

Hey.

First off, ignore @jasonbourne52

I have some first hand experience with the same amp! A friend purchased one a few years back - he wanted an inexpensive tube amp - liked the look of glowing tubes. We did some research and he ended up getting the Oldchen.

He did not manage the amp very well... Was left on 24/7 with dodgy speaker wires being disconnected intermittently.

Here’s the thing, not s single problem with it! Tubes didn’t blow, transformers survived, capacitors didnt spontaneously combust, he wanst electrocuted and the house didnt burn down...

I’m amazed the thing kept running! He recently gifted it to me (I’m an avid DIY guy...) The tubes it came with were crappy to begin with, and he never upgraded them. I put a Winged-C Black plate rectifier tube in in, some Psvane Phillips EL34 replica tubes and a pair of vintage RCA 6SN7’s in the amp. Quite nice sounding!

I have since stripped it down to its base components and will be repurposing it and turning it into a 5 or so watt power amp. When you open it, be prepared to see silicone covering every solder joint! Its not easy to remove. In fact, I would say its impossible. Thats why I decided to strip it down completely and use the parts for a completely new build. Too much headache trying to work around the silicone and solder in new parts. So, I pulled the transformers, the choke, connectors, tube sockets and the rest is headed for the trash heap. I have all the parts (capacitors/resistors/wire etc) and will be building a new chassis and amp from scratch.

All that to say, if the solder joints are covered in silicone (mine was pt to pt wired), the just put some nice tubes in it and enjoy it. It will certainly let you know if you like the sonic signature of a single ended tube amp without breaking the back. If you do, then you can go hunting for a 211 or 845 based amp :)

Enjoy!

And as others have stated above.

Tube amps are high voltage devices, and can "hurt" (yes, speaking from experience...)

Only ever put one hand in the chassis at a time, unless you have discharged the caps and it is unplugged. I got a rather unpleasant shock when putting one of my DIY projects on the shelf after working on something. Fingers went under the wooden base of the amp and touched some wires. This while my thumbs were on the metal top of the chassis. 

I have a slightly bigger chinese tube amp (Willsenton) running Klipsch Cornwall IVs and without having any tube amp to compare it with I find the combination very sweet. Just yesterday I played some music I hadn’t listened to in ages and again it was sonic revelation. If I had any knowledge whatsoever about wiring, soldering, etc. I’d probably also have a look under the hood. So far I’m happy finding out how far rolling tubes can bring me. 
Enjoy this adventure!

Thanks for all the responses. After a few hours of listening I am generally pleased with the $150 spent. I may pass on upgrading as I saw the silicone inside and have zero interest in prying stuff loose. It will remain as is and be enjoyed. Tubes may or may not be my thing. Stressing over heat, bias, and high voltage may get in the way of just listening. The engineer in me may just be too curious to actually enjoy them. 

Good call on the internal mods :)

After seeing how the amp survived my friends rather “careless” treatment of the amp, I wouldn’t worry too much :)

Oh, and he kept it in a confined space in an entertainment unit. Got really toasty in there!

Live with it for a bit, see how you like the sonic signature. 
 

And tubes, the “maintenance” of tubes and the care one needs to observe, isn’t for everyone. Nor is the sound they produce. That’s in your hands to decide :)