Fosi Audio BT20A Bluetooth Amplifier for Speakers, Mini Stereo 2 Channel Amp Class D, with TPA3116 Chips 100W x 2 and Bass Treble Controls, for Home Audio Outdoor Passive Desktop Bookshelf Speakers

I bought this on a whim and it has turned out to be an excellent purchase. I bought it with 15% off so it was just over £70.00 and at that price I feel it to be very good value indeed. It is certainly a small amplifier and ideal for anyone with limited space. It has metal casing and feels very solidly built. This gives me confidence as so many items seem flimsy these days. I use it mainly with a CD player and the sound quality is superb and certainly loud enough. Using it for streaming over Bluetooth is also excellent. The only downside is that I find the volume etc controls a bit small and fiddly to adjust. Not a major problem really but a remote would have been nice even if increasing the price slightly. I was so impressed with it that I also purchased a BL20A a few weeks ago. That too is an excellent amplifier and I have reviewed it separately. Overall I cannot fault Fosi products and would not hesitate to buy from them again.

Last year I had bought a Tangent Ampster BT II amplifier, which had worked great, however it recently had an issue with the power switch, so had to be sent away for repair. As I used it in my office I needed a replacement and decided to order this amplifier. I thought the Tangent Ampster was small, but this BT20A amplifier is ridiculously small! This is mainly as the power supply is external to the amplifier, which itself is bigger than the amplifier. I have it connected to a pair of Mission LX-1 MKII speakers, and I am happy to say that this amplifier easily runs these speakers, with no sign of distortion. I appreciate the treble and bass controls, as by default the treble did sound lacking and a bit stifled. The dials are nice and smooth, and the power switch toggle works without issue. At this size and price you only get 1 set of RCA inputs and 1 set of speaker outputs, but for my use case this is fine. Bluetooth works seamlessly, and the audio quality is about on par with direct RCA connection. Be aware that if you connect via bluetooth it will override the RCA input, even with no music played over bluetooth. I will say, as others have, that being able to connect to the amplifier via bluetooth without being asked for a code is a potential issue, I live in a block of apartments, so anyone could connect to it if they tried. I don't hear any hissing when not playing music, so that is another plus. Overall a great little amplifier for the price, once my other amp is back from repair I will probably relegate that to the living room as it has a remote control that is more useful.

It’s ok. I managed to get it with £16 off so ended up paying £64. It’s hard to complain at that price. Sound quality is not too bad. Crystal clear but nothing to shout about. I’ve only used it playing Tidal via Bluetooth so the RCA input will probably provide better quality audio. A decent option for casual streaming and probably best suited to hooking up to a computer using passive speakers

I had a Cambridge Audio amplifier, which has finally given up the ghost - annoying crackle and cut-out on one side of the stereo. It was driving me mad. I listen to classical music a lot. Looking around for a replacement stand-alone amp was proving costly - I have a brand new CA CD player and good CA bookshelf speakers which I didn't want to junk (which I'd have had to if I'd bought a self contained hi-fi system, which at first seemed the only option) Looking around on the net I found this amazing little piece of kit and thought, well, this is so cheap that even if it's not up to much it's better than half the music being cut off periodically by my dying CA amp, and I went for it. It's astonishing. It has plenty of power, and its treble and bass controls are very useful - my old amp didn't have those - as I listen to old recordings too which sometimes need a bit of bass boost or treble cut-back. I have a mass of music on MP3 files on a computer in an adjacent room which I can now listen via the excellent reliable Bluetooth connection. The CD player connected to the little amp works fabulously too. The sound quality has plenty of presence and is not remotely tinny or restricted, which I'd feared with such a little machine. This is a brilliant idea and a mini-revolution in amp design. The folks at Fosi have found a serious hole in the market and plugged it with a great range of innovative and smart kit. Very highly recommended!

I brought the first amp a while ago and sent it back as I wasn’t happy with the sound quality or output. I think I said it may be ok for a small broom cupboard. Roll on 2 years or so and having re-read the reviews I decided I would give it another go With a fresh set of ears Maybe I had a bad one last time of they have tweaked the firmware or something, But it’s a very different amp from the one I recall - To my surprise this one was excellent- I would say unbeatable for the price. Ok so some complain that the Bluetooth is not protected so anyone can jump on it and that would be a nice extra but it is what it is. It’s driving a couple of external speakers with a well known home assistant input for the garden and I’m seriously impressed. Also tried some mission bookshelf speakers I had spare. Bass and treble are adjustable and work remarkably well. Bluetooth seems solid and clear; aux in is even better. Recommendation: set bass and treble to 50% (pointing straight up) as a starting point, this will give you a good reference point. I’m really fussy about sound and wasn’t expecting much but I’m really glad I gave this little beast a second go. I would absolutely recommend for small or mid size room.

I bought this Fosi amp (BT20A) 2 months ago having read mixed, but mainly good, reviews. I have it connected to a pair of Maudant Short MS20i speakers which were previously connected to a big Technics amp. I'm not an expert on sounds, but I like a good sounding stereo, and this amp with music from my phone (spotify) bluetoothed to it is great. It's plenty loud enough for an average living room and the clarity is excellent, and the adjustments for bass and treble are simple and effective. I think it's as good as the Technics amp (SA-EX320) soundwise, but much simpler with a lot less functions - but it does have bluetooth! I listen to music from my phone via bluetooth, and I have the optical out from my TV through a converter into the RCA inputs. Both sound great (to a non audiophile) with the only very slight issue being that occasionally when the TV is off and nothing is connected to the BT, if the volume is high some small clicky noises can be heard, but that may be the cheap optical to RCA converter I am using. The power supply is a bit of an eyesore compared to the sleek little amp itself, so I had to hide that (and a load of other wires) in a cable tidy box. The picture shows how tiny it is next to a Tivo box. I'm really glad I bought it and I would happily buy another if needed, but I am a bit miffed that in the 2 months since I bought it the price has dropped from £70 to £60! It is a bargain.

I have read many reviews of similar items and decided to plump for this one. Chinese no-brands tend to amaze and disappoint in equal measure. It arrived today, the power supply is actually wider than the amp itself. The amp is made out of metal and rather nicely finished. Incidentally the power supply is 24v 4.5 amps, 108 watts and claims to be certified by TUV and GS two highly respected German Laboratories. Even so, its probably a good idea to check the fuse in the plug is 5a if you intend to leave it left switched on. This unit claims to contain two Texas Instrument chips for amplification and one by Qualcomm, the latter presumably for Bluetooth. I found some old QED speaker cable I had lying around and hooked it up to an old pair of Tannoy Eclipses I have owned since the eighties. I have to say, so far I am pretty amazed by this unit. It‘s very clear, detailed and loud with loads of bass. I would estimate equally it is as good as one of those £500 Japanese hifi stack systems from the eighties. Is it hi-fi? Hi-fi is as good as your hearing and to get great sound you have to pay a lot, so who knows. I would say this is a bargain and would be great to use with a couple of old speakers sitting in the loft. Certainly better than most portable speakers folk use these days. Some have experienced a problem with the Bluetooth, well it says it supports BT5.0, i have an iPhone 13 and it sounds great, so can only presume they had a defective unit or possibly phone. Someone suggested it really needs a remote control, well maybe if you connect via the phono sockets yes, but don't forget you can adjust the volume for bluetooth on your phone. Altogether (and yes it’s early days) a rather terrific and great value little amplifier, it’s going in my study so I can turn it up loud without bothering the neighbours. :-) Added 31/12/2021…. Someone criticised this for the way Bluetooth was implemented and the possibility of others having access to it. Well in theory, yes they can as there is no PIN, but there isn’t on most similar pieces of equipment. However if you switch it off and unplug, this is not a problem. My Sony headphones connect automatically when they are turned on. This amp only connects when I choose to on my iPhone, it doesn’t connect automatically once paired, which I think is a good idea for this type of device

I used this unit to drive pair of floor-standing speakers which I use with my PC (I like decent sound quality). This unit delivers punchy bass with no background noise on either the aux input or via Bluetooth. I'd had background noise problems with the previous amplifier (a Tangent 50W per channel unit), probably due to a ground loop. The Fosi BT20A unit background noise is completely inaudible. The unit is also very small (about 1/10 the size of the amp it replaced) but with the same output power. This is probably due to the fact that it is a Class D amplifier which makes it very efficient. It is more than capable of filling the room with sound at concert hall levels. The only issue I've had is that occasionally the Bluetooth input will not reconnect after the PC has been asleep. This is easily solved by briefly cycling the BT20A power. In short, I'd happily buy another.

Works perfectly! I used this to fire up a pair of outdoor speakers that came with our house, and it’s been flawless. Super easy to connect via Bluetooth, and the sound quality is great — clear, strong, and consistent. I’ve left it on pretty much all the time, and it’s been running solid for about 8 months with no issues at all. For the price, this little amp delivers big performance. Highly recommend.

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’ve had it for a year and no problems, great sound

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.

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