BT20A Bluetooth Stereo Amplifier, 2 Channel Home Audio Component Amplifiers for Passive Speakers, Mini Class D Amp Receiver 200W for Indoor/Outdoor/Garage/Ceiling/Bookshelf Speaker

TL;DR: This works exactly as it should. Great piece of equipment is such a tiny form factor I've been meaning to setup a more permanent outdoor speaker solution to my backyard and was going to go with the old fashioned "run 200 feet of speaker cable" because the high receiver I bought was pretty far away and I was going to use Zone 2 for the speakers. But this little package came up on my searches and it was exactly what I wanted and more. There is an area in the backyard that we set up outdoor movies at and I use a portable speaker for sound. Instead it dawned on me that not only can i stream music from any source with this bluetooth connection to this device, I can also double up and use it for outdoor movies if I place them correctly. Well I found an outdoor telephone jack and indoor jack and I was able to run audio cable outside through those openings which were right next to where I would put the movie screen. So I was able to put two outdoor speakers in a place so that it can provide sound for movies AND they are in a general area that I can stream/play music for the backyard in general. No need to wire anything from the receiver and eliminates the need to bring out a boombox outdoor speaker for movies. What I was really happy about is how fast and solid the bluetooth connection is. I use an old laptop for streaming music and store all my ripped CDs. I thought I was going to have to hardwire the laptop to this Fosi amp because the laptop is like six years old. After a little work and trial and error, I finally figured it out and it works. The first time the laptop had a hard time finding it but now that it is in the list of known devices, it connects flawlessly. I tried iphones, tables, etc. and all of the newer devices find it with no problems. Even my echo show found it and its about 40 feet away in another room. Movies sound great, have my Lounge music running at night and I'm so happy about this setup. And, going back to my resistance to running cable, I only need 30 feet of outdoor cable for both speakers so it was convenience too. Highly recommend this product: very inexpensive, does exactly what it is supposed to and greatly enhances the flexibility of what you can do.

I got this to run some higher end home audio speakers installed outside for the yard/pool area at our house. The speakers are $300 each and I had been running it on an older Sony coil-based home theater amp because I thought I needed the zones and independent volume controls/management for tone/eq. The amp in the cabinet indoors was putting out quite a bit of heat when it was powered on whether they were in use or not. The wiring was a total mess and I bluntly didn't enjoy dealing with it. I went in to this project assuming I was going to get a Denon, Onkyo, Yamaha, or some home audio mixer board + eq, or something fancy with roughly $2k budget... I was on struggle street trying to piece it all together. I only need a simple input amp. I have a cheap class T amp in my garage that works for what I am doing there, but the audio quality is trash. I rolled the dice and picked up a few of these and man, they blew my mind. They have a lot of punch/power and the audio quality is REALLY surprising compared to the old stuff I had. The BT connection is ROCK SOLID. A lot of these cheap china BT interfaces are trash and buggy. This thing pairs right up and is solid and reliable. I'm waiting on the splitters to feed the source to all of them, but per zone, they're superb. Super straightforward install and good labeling, pair with FosiXXX and go for BT. It's a small, light package and the box it comes in is pretty good for it's weight and has some heft. Not sure whether the weight is from the case or components, but it's a mosfet so we'll see about heat dissipation down the road and whether it does a thermal cutoff or not. I might end up getting more for the garage after a few sessions in the backyard. I was pleasantly surprised!

I’m very impressed with the Fosi Audio BT20A. It’s compact, well built, and surprisingly powerful for such a small amplifier. The Bluetooth connection was quick and stable, and the sound quality is clear with plenty of power for my speakers. The controls are simple and easy to use, and I really like the clean, minimalist design. It’s also great that it doesn’t take up much space, making it perfect for a home audio setup. For the price, the performance is excellent. Highly recommended for anyone looking for a simple, compact, and powerful Bluetooth stereo amplifier!

This is great! I have this connected to two Polk TSI100 bookshelf speakers and no issues filling the room. 14awg wire banana clips. I’m getting into the world of hi fi and started at level 1 and do not regret it. Start at the bottom and work your way up before you spend $1000 on an amp. Yes there may be better ones but at the end of the day, this works for my living apartment and I’m moving it into my office. The speakers were attached to a Bluetooth Sherwood RX 4508 and there was a faint hiss. Nothing yet with this Bluetooth amp. Again for under $100 it does the job. Great value for the money. Easy to set up. Using Spotify lossless but it’s a Bluetooth connection. Happy I bought it so far!! It fits in my hand. Tv soundbar is behind the amp.

It is fine - really fine! Five minutes in to using this little amp in my workshop with my formerly-dust-collecting Proton speakers, it works great! I can power these old 8-ohm speakers loud enough to hear over my screaming power tools and dust collector. See the photos. It paired thru Bluetooth with my Pixel 9 flawlessly. Simple controls. Plenty of power. The speaker wire posts look like they are gold plated (that would be surprising - they are likely polished bronze, but that's still good). It is worth it? Well, it wasn't free, but it cost a LOT less than my speakers did back in 1990 (not adjusting for inflation!)

So far, so good. This setup fits my needs perfectly for playing music on my patio from my iPhone via Bluetooth. I paired the Fosi amplifier with a pair of Polk Audio Atrium 8 outdoor speakers, and the combination has exceeded my expectations. The amp has plenty of power to drive the Atrium 8s, and they sound fantastic—clear, full, and more than loud enough for outdoor listening. Overall, I'm very happy with this purchase. The only thing left to see is how well the Fosi amp holds up over time, but based on my experience so far, I would definitely recommend this setup.

I’ve been using the Fosi Audio BT20A as part of a small speaker setup, and it’s impressive how much performance it delivers given its size. The unit is **roughly the size of a small jewelry box**, making it easy to place on a desk or shelf without taking up valuable space, yet it feels solid and well-built. Despite the compact footprint, the amplifier delivers **clean, controlled power**. It drives passive speakers confidently, maintaining clarity across low, mid, and higher volumes without distortion. Bluetooth pairing has been quick and stable in regular use, and the wired input has been equally reliable with no noticeable noise or interference. From a technical standpoint, the amp runs efficiently and stays reasonably cool even during extended listening sessions. The volume control is smooth and precise, allowing for fine adjustments rather than sudden jumps. Overall performance consistently exceeds what you’d expect from something this small. This is an **excellent compact stereo amplifier** for desktop or small-room setups. If you want strong, clean audio from a unit that takes up about as much space as a small jewelry box, the BT20A is an easy recommendation.

Unlike other posters for this product, I did NOT use the FOSI BT20A as my primary amp. Instead, I used it to wirelessly connect my old circa 1979 2226B Marantz amplifier to my old 1985 JBL 4312 speakers. To do this, I also bought a Bluetooth transmitter/receiver dongle which I attached, in TRANSMITTER mode, directly to my Marantz speaker outputs. I then hooked up my JBL speakers to the FOSI unit using banana plug adapters. The FOSI will accept either banana plugs or bare wire. My speakers are bare wire, but I opted for the plug adapters as they seemed the cleaner alternative. The FOSI amp is a Bluetooth RECEIVER, so whatever gets transmitted from the dongle attached to my Marantz in TRANSMITTER mode will be caught by the FOSI RECEIVER amp and pumped thru the speakers. And there's your wireless connectivity! I have had this setup for only about a week now, and I'm still experimenting with different settings. The first thing I discovered is, that if you're using another amp as the primary amp (the Marantz, in my case), you had better turn the bass and treble controls on the FOSI down to a bare minimum (or altogether off), otherwise you will have a tremendous amount of distortion, especially in the midrange. I'm using the Marantz amp to control the bass/midrange/treble, and the tone boost the FOSI provides can be painful. If, like me, you're using the FOSI to resurrect an old stereo system, I would recommend you start with the FOSI bass and treble at zero (6 o'clock) and the volume at a quarter (9 o'clock) and adjust both your primary amp as well as the FOSI from there. Currently, I have my FOSI bass and treble at just a bit over the minimum, while its volume is at the halfway mark (12 o'clock). I may slightly readjust, but this is working well for me now. The FOSI sound quality is somewhat on the bassy side. Its volume is tricky. I suspect it's 50 watts per channel, totaling to the advertised 100, but that's still a lot! Midrange can be tricky, especially at louder volumes, where you may get a blaring distortion, unless you really play with bass and treble. This is why I recommend fine tuning the tone and volume controls on both your old amp and the FOSI, if you're planning on using it to make an old stereo system Bluetooth. Small increments/decrements on either end will produce noticeable changes. I primarily use my stereo to play old vinyl, and this is where I'm still struggling with the sound. I have also adapted my old Marantz to be a Bluetooth receiver (with a separate receiver dongle) and play my phone thru it. The Marantz captures my phone tunes from the receiver dongle, transmits them thru the transmitter dongle to the FOSI receiver. The sound quality is admittedly better in 100% digital format. The FOSI is only about 12-14 feet away from the Marantz primary amp, so I cannot speak on range. However, my amp and its components are in a closed cabinet and there is a wall between it and the FOSI. I have not had any issues with connectivity. Sound is clean and uninterrupted no matter what else we have running. Bluetooth connection is a snap between my transmitter dongle and the FOSI, especially if the transmitter is ONLY used with the FOSI, as in my case. Once first contact is made. both units will remember their last connection. Hope this helps if you're trying to bring new life to your OLD stereo system!

高品質なサウンドが楽しめて喜んでいます。テレビとは有線で、スマホとはBluetoothで接続。Bluetoothで繋ぐとテレビの音は消音されるので、外部入力よりBluetoothを優先します。 シンプルで小型なのにパワフルで喜んでいます。

Este amplificador fue una excelente compra junto con un preamplificador Fosi Box X2. Como alguien que le gusta la música por hobby, me sentí muy bien de cómo quedó armado mi audio. Conectando el preamplificador a este amplificador, puedo escuchar mi música de mi tocadiscos, y cuando necesito utilizar las bocinas para ver un video, una película, o escuchar música, se puede conectar este amplificador por bluetooth a mi laptop o mi celular sin necesidad de moverle nada, solo con que esté encendido y no haya nada corriendo simultáneamente. Y la conexión es ultra rápida también. También si compras bocinas que sus cables no tienen la punta dorada (es decir es puro cable) este amplificador viene con manual y puntas de plástico para instalarlas sin tener que comprar los tips por aparte, y es muy sencillo conectarlas.

Ich bin sehr zufrieden und gebe eine Kaufempfehlung. Für mittelgroße Partys ist das kleine Teil gut geeignet. Es hat wirklich eine gute Power und Lautstärke bei gutem Sound. Bluetooth klappte reibungslos. Wer die Wände wackeln lassen möchte, oder 100 Leute open air beschallen, sollte vielleicht noch eine Klasse höher gehen.

Mój amplituner Onkyo zajmował miejsce w moim minimalistycznie urządzonym salonie , dodatkowo nie posiada bluetooth , więc zakupiłem Fosi Audio , i.... Nie jestem melomanem i pewnie dla tego :-) nie słyszę różnicy między tymi wzmacniaczami , więc polecam wam też bo większość z was tak jak ja jej nie usłyszy

I have been using this amplifier for a month now. It is working without any issues. The build quality of the amp as well as the adapter is very good. Looks tiny besides my old amp. My Old amp stopped working so am using this amplifier as an temporary alternative to power a set of Solidaire SS100 bookshelf speakers with a 12-inch woofer, a 4-inch midrange, and a 1-inch horn tweeter with impedance of 8 Ohms. Bluetooth range is also good. Comparable to my existing Logitech Bluetooth adapters. I have noticed it does not get warm on long usage when listening at acceptable volumes at home. The audio quality is flat and commendable in the Fosi amp, but I seem to miss the warmth my old Solidaire AS1200D amp provided. So, I tend to boost the lows and mids from the equalizer to get the desired effects. My decision on buying this over Aimyia amp was swayed because FOSI provide a warranty on their product, but Aimyia brand amps have no such mention in their listings.