Fosi Audio BT20A Bluetooth Amplifier, Mini HiFi Stereo Amp Integrated Receiver for Home Audio Passive Speakers, BT 5.0 Class D 2.0 Channels, 100W x 2 TPA3116 Chip, Treble & Bass Control Knob

Product Information

I found the slogan on this box, Hifi Made Fun, kind of ironic because too me, the Fosi wasn’t really that much fun.

Next, we have an entire bunch of inexpensive amplifiers coming from under the same roof. They really go close to each other, especially considering their prices. On the other hand all of them have distinctive features that make them serve same purposes, but with different flavors. Fosi Audio BT30A is a mini amp that can probably go first, because it shows a good balance between power and frequency. Fosi Audio BT30A gives 50 watts per channel, which is pretty good for a small unit like that plus a 100 watt for a subwoofer channel. It only weighs less than 2 pounds and small in size, so it can fit on a desk or a shelf with no issue. It can also be moved around easily, because protected by durable aluminum casing. Inside the BT20A Pro you will find a Texas Instruments TPA3255 Class-D amplifier chip and four TI NE5532 Op-Amp chips. While two of the four chips are soldered onto the board, the other two can be replaced. Fosi lists the compatible replacements, which include the LME49720HA, MUSES02 120-140, OPA26041P, OPA2134PA 25-35, LM4562 and NJM4556AD. That gives you a huge variety of customization, if you so choose. You could say it’s fun because the cheap price allows new buyers to get interested in the hifi hobby. That’s why I think people building their first stereo system or someone who wants an inexpensive second system will find the Fosi fun.As for the turntables do not have a built-in preamp, you need to add an external phono preamp before connecting BT20A. But once I switched to the Pro version, I noticed new things around the music such as extra reverb and different effects throughout the song, especially on Chris’ guitar playing, which were muted a bit in the original BT20A. You can think of Fosi Audio BT20A as of a modification of its sibling in the previous entry. The main difference is that BT20A doesn’t have a subwoofer output, but provides twice as much power per each channel, 100 watts each. Same small size, but with a slightly different design with all three knobs of the same size and style, which makes it look somewhat cool. The Emotiva and Cambridge amps, even though they are more expensive than the Fosi, will provide you with a more lively listening experience and you will hear things in your music you’ve never heard before.

Thanks for sending this in for testing and to @amirm for his time in doing so. Also very kind of Fosi Audio to offer ASR members 20% off, kudos. A more sophisticated amplifier with added features and better Bluetooth connectivity with a range of 50 ft. It has a built-in speaker protection circuit, the TPA3116D2 Chip for hi-fi sound, as well as bass and treble control. I agree that it’s a bad idea to quote maximum power as the nominal number. I don’t know of any major Hi-Fi amplifier brand that does that. It is interesting to see exactly what momentary power is, as dynamic sound comes from the ability to handle transients, and 300W, even if it’s just for a second, can make all the difference. A tiny amp like that driving speakers at even 75W per channel with low distortion would be impressive enough. Now, let’s talk about the PROs of owning this little amplifier next: The Pros of Owning the Fosi BT20A Amp Size:

🍪 Privacy & Transparency

Please reconnect the power supply to the BT20A, and move the BT20A to another room to have a try. • Restart the BT20A and then try to connect again, try to use another Bluetooth device. But what‘s the deal with the „225W“ power figure? That‘s the chips spec at 10% THD, not the amps actual output capability. Everybody in the chipamp space does it, but that doesn‘t make it any less disingenuous … The BT20A Pro has a 3.5 mm pre-out on the rear of the unit that is not found on the original. This means that you can use the Pro as a preamp or connect it to a subwoofer. Note the BTA20 Pro (bottom) has the 3.5 mm Pre Out Fourth Major Difference: Bluetooth Volume Knob Connection But, let’s talk about the definition of “fun” because maybe my idea of fun is different from Fosi’s and even yours. What is the best budget stereo amplifier? A good amplifier will make your speaker sound louder and better, but keep in mind that it will not make a bad speaker work like a good one. The first thing to consider is power output. We advise you to choose a model that delivers power equal to twice the speaker's power rating.