IWISTAO FU50 Small 300B 2x8W Vacuum Tube Amplifier Finished Board Kit Single-ended Class A DIY Free Tuning
Vacuum tube FU50 is known as the small 300B and close to tube 300B, but the price is much lower than tube 300B, its treble is fine, extension is very good, overtone is excellent, and the vocals are very cordial. Listening to the original sound of the Dream of Red Mansions can feel that it is super strong; listening to symphony and string music is very good, violin is very delicate, more worth playing than the tube EL34.
This kit's solution uses 6J8P for gain amplification driving, FU50 as single-ended class A output, and tube 5U4C as tube rectification. Its output power is 2x8W. Don’t underestimate its 8w output, it is a Class A state, and much better than the digital power amplifier 50WX2 output and also more powerful than the LM1875's 2x25W.
This finished board is free tuning, you need just insert the vacuum tubes, and connect output and power transformers. Also, kindly remind to connect your speaker to avoid damaging the output transformers before power on. The kits are made of fine materials and all imported high-voltage capacitors ensure safety and stability. All the seats are gold-plated to ensure good contact. High-power resistors use Panasonic, KOA and other advanced fever resistors.
Meanwhile, we provide the scheme diagram for you information. This is a channel of amplifier part below.
And, there is a power supply part below.
Here is the tubes, FU50, 6J8P, 5U4C.
After you insert the tubes into this small 300B amplifier board, you will get it as photo showed.
More detail, please find,