Warning: China-Hifi-Audio.com

I bought a r800i 300B 845 amp from China hi fi and paid the $595 shipping. I figured some of that might be profit, but it was still a good deal if the amp was a good quality piece. I knew it was a bit of a gamble, but I've bought crap products and had horrible customer service in America too. That said, a 100 pound amp from China was on my doorstep in five days. I'm still amazed by that! The amp was great. Non fatiguing with that single ended triode sound, just a little flat and grainy, but it still needed to break in. I replaced the 12AX7 and 6SN7 input tubes with some I had on hand and it got really good. I bypassed the bias supply and cathode electrolytics with some cheap .1uF film caps I had on hand and now it sounds fantastic! One thing is for sure, I would never have had a 300B/845 amp if I had to buy it from anywhere else, it would have remained a dream. I would love to buy this from a U.S. manufacturer, but it would have cost more than I am willing to pay. My guess is the U.S. price would be many multiples of the $2K I paid. I was going to build a GM70 amplifier and the cost of transformers and chokes (cheap iron, not the good stuff) was well over $1K. I think it would be wise to remember that the people of a country and the government of a country are not necessarily the same. I definitely don't think the current US government represents me very well. I'm not encouraging anyone to buy chinese, but I discourage lumping all people of any country together. Anyway, my amp kicks arse!

Have you measured the voltages in your amp? I have seen some pretty high B+ and (especially) filament voltages in some Chinese amps which lead me to question their long term reliability. A few resistors may save you heartache.

Not yet. I opened it originally to check bias because the instructions didn't provide a meter reading-to-bias current description, at least not in English. I opened it a second time to add a couple of bypass capacitors because I've come to the conclusion that electrolytic capacitors and diode switching is responsible for much of what we call electronic/solid state sound. I was afraid to use my meter to check voltages because it's not rated for the 1000 volts 845 tubes usually run at. (Of course I could have checked filament voltage, but I forgot.) I've since removed my head from my butt and remembered that I could measure voltage drops across various components to deduce the rail voltages, but I haven't opened it again yet, too busy listening to music and shaking my head that I own something this cool. The only problem with this amp is the rectifier tube arcs on startup with some of the different 12AX7 tubes I've tried. It looks like the input stage and possibly the 300B drivers are tube rectified, while the 845s are rectified via solid state diode strings. I think the first capacitor following the rectifier is too large, but the power supply components are on a circuit board and it requires a bit of effort to get to the solder side to see "what's doin". I'll check soon.

300B and 845 filaments are 5 and 10 volts respectively. B+ for 300B and 845s is 260 and 945 volts respectively. 12AX7 and 6SN7 heater voltages are 12.6 and 6.3 volts. I fully expected the voltages to be "close enough", but they were essentially perfect. I forgot to mention that I unscrewed one of the output transformers thinking the enclosure was hollow and a small output transformer was hiding inside. Nope. Large potted output transformers. This is all in reference to the Willsenton r800i 300B 845. I have paid a lot more for a lot less. I feel like I stole the damn thing at the price it's being sold for. Mine was a return so it was $400 bucks cheaper and had a couple of small scratches on it. The tube complement alone could easily cost half the price of this amp. The other Willsenton amps that have been reviewed by the online and YouTube community have gotten similar great reviews. 

Hmmm. But what about all of your cell phones and computers, and washing machines and refrigerators, all built in China? Are you simply looking the other way and holding your nose while using your cell phone? Seems a bit hypocritical to bash Chinese built gear and classify it as poor. Some is excellent. I’ve a Grant Fidelity sponsored Shuguang tube kt88 integrated whose sound I’d put up as an extremely solid 8 of 10 sound and build wise. Critics!