






🎶 Elevate your sound game — because your speakers deserve the BL20C boost!
The Fosi Audio BL20C is a compact 2.1 channel Class D stereo amplifier delivering up to 320 watts of power. Featuring Bluetooth 5.0, U-Disk playback supporting multiple audio formats, and versatile RCA inputs, it drives passive speakers and powered subwoofers with hi-fi clarity. With smart protection, low distortion, and customizable sound controls, it’s engineered for professional-grade home audio experiences.



















| ASIN | B077QPTPVW |
| Audio Output Mode | Stereo |
| Audio Output Type | Speakers |
| Best Sellers Rank | #140,125 in Electronics ( See Top 100 in Electronics ) #836 in Audio Component Amplifiers |
| Brand | Fosi Audio |
| Color | Black |
| Compatible Devices | Smartphone, Speaker |
| Connectivity Technology | Bluetooth, USB |
| Connector Type | RCA |
| Control Method | Touch |
| Controller Type | Android |
| Customer Reviews | 4.5 out of 5 stars 923 Reviews |
| Format | WAV, WMA |
| Item Weight | 2.3 pounds |
| Manufacturer | Fosi Audio |
| Mfr Part Number | BL20C |
| Model Number | BL20C |
| Number of Channels | 2 |
| Number of Items | 1 |
| Other Special Features of the Product | Volume Control |
| Output Power | 320 watts |
| Output Wattage | 320 watts |
| Software Update Supported to Date | unknown |
| Special Feature | Volume Control |
| Surround Sound Channel Configuration | 2.1 Channel |
| Unit Count | 1 Count |
| Warranty Description | 24-month manufacturer |
| Wattage | 320 watts |
| Wireless Technology | Bluetooth |
S**P
Blown Away!
Although I had watched many great reviews on this item, such things remain very subjective. I had fairly high expectations from the reviews, but still really didn't know what to expect. I was able to compare it to another popular budget brand unit in a similar price range. Although this other unit was built well and had a bunch of great features....in terms of sound and power...there was absolutely no comparison. I was amazed at the clean power and volume of the Fosi. I first ran it with Polk Mini Monitors which are small bookshelf speakers with 5.25 drivers. I just couldn't believe what I was getting out of those speakers. I then switched to a much larger set of floorstanding speakers with 8in drivers. Again... Just Blown away! This little Fosi had no problem driving them with great sounding bass, mid/high clarity and plenty of headroom. I honestly don't think I would ever have to turn this unit up beyond 12 o'clock. The Fosi is built well, the Bluetooth works great, I love the USB input, it sounds awesome and the price is more than right for what your getting. It's tiny and puts out good clean power. I wish I had some 3 way speakers with 12in drivers to test this on. In any regard, unless you need something highly specialized, this amp should make you very happy. I highly recommend this Fosi product!
H**N
The hype is real, how is this thing only $80?
The hype is real folks, I have been seeing cheap audio man or budget audiophile reviews for years that raves about anything dirt cheap that Fosi audio makes. I do have one of those cheap chinese tube apps that lacks a sub out. Recently bought a deal on a good subwoofer and I need to build a 2.1 system for my home office. The home theater receiver have funky responses on bass so I needed a dedicated stereo amp for my build, and this amp is so well reviewed and within anyone's budget, that I had to give it a try. Thank god I did, this is everything I need, it is powerful enough to drive desktop speakers, and very good for a powered sub. The sound is crystal clear and punchy, does not sound cheap or lacking any power whatsoever. For anyone that are crunching on a budget, get this little amp, I'd say you will have to spend at least 3 times what this amp cost for the next best thing in line.
A**R
Works well, Power supply is small (Beware)
I needed something outside to power my dual channel Polk Audio Atrium8 speaker. I actually went out and bought a Sonly receiver, your typical brick bulky receiver. I then found these little units and wanted to give them a try. I opted for this Fosi Unit I have the little thing mount behind the TV (On the back of the TV) so its out of sight type deal. Sound is great, better than the giant receiver One thing to note and there is another review about this, this power supply it comes with cannot produce 320w with the 24v/4.5A power supply. I upgraded the power supply to the 32v/5A and this gave me about 80W per channel and was good enough. I did email Fosi Audio support and asked what power supply is out there that can produced the 320W and they where unable to find me an answer. So why they have this listed at 320W, I don't know but just be careful. I think out of the box you will get 60W per channel at best. With this I give it a 4 star review. Aside from this the unit does well. Have it hooked up to the TV so football games are nice and clear and the unit also has Bluetooth
P**N
Audio Performance Impresses
The Fosi BL20C 2.1 amplifier form factor is small and compact. It conveniently fits nicely in a variety of different locations. The case is solidly built metal. The control knobs rotate smoothly with stepped detents. It fits nicely just beneath one of my monitors. Audio Performance Impresses. The amp power pumps out the loudness DBs upon demand. I run with the amp cabled directly to my PC. I bought this amp primarily for listening to music. Depending on the file format type, quality of the file source, and media type, the sound bass and treble defaults can vary quite a lot. The BL20C allows the listener to custom tailor and tune the listening experience, based on preference and the variable sound source. I'm running a pair of Klipsch R-41M bookshelf passive speakers, along with a powered subwoofer Polk Audio PSW108. Both are 8 ohms. The BL20C allows me to custom control all the speakers from a single control source. I found 1st setting the PC OS 'sound' level at about 80%, then secondly tuning the amp bass/treble control levels to the best front speaker sound, then 3rdly setting the independent active sub bass woofer volume level and low pass filter level. After this, I only needed minor amp control bass/treble adjustments based on the music song and source. Just to see what my system was max ultimately capable of, I set the PC OS sound output to 100%, set the BL20C amp bass/treble controls to the middle position, played a musical song from a music file source that I had ripped from CD, then cranked up the amp volume gradually to max. It was very loud and clear. My speakers are rated for the amp wattage power output, so make sure your speakers can handle the Wattage output. My next BL20C test with the Bluetooth functionality. I found if I simply flipped the front panel switch to "BT/USB", the device started broadcasting a BT signal. My mobile device instantly recognized the signal. I added/accepted the BL20C amp device to my phone. Playing some songs from my mobile device, the BL20C received the music stream from my phone fine, then outputted the audio signal output to my speakers. Considering the music source was coming from a phone, the music quality, volume, and adjust ability was impressive. I still haven't tried out U-Disk features yet. The Fosi BL20C 2.1 amp accomplishes what I set out to do. I am certainly enjoying it. The interface versatility is definitely a plus.
M**N
Surprisingly capable small amp
For starters, this is only after a couple hours of continuous usage, so things may change. For now, I'm very happy with this thing. I ordered it and some Micca RB42s and snagged some Memphis Audio speaker wire from a local store. So this thing paired instantly to both of my phones and my tablet, and the rca input connected to my record player was problem free. Front controls feel nice and have notches as you turn them. Buttery smooth. I haven't tested the sub output yet as j don't own a sub, but that should also work just fine with the right sub. Construction feels nice and heat management seems fine after these couple of hours so far. As for sound quality, I'm new to amps and passive speakers, but this is pushing the Micca's really well and everything sounds wonderful. No noticeable distortion or anything but I haven't cranked it yet out of respect for the roommate. Maybe when he's gone for a day... Chassis feels solid and durable, but not sure if it can be easily disassembled for people who want to tinker or change op amps. It's small size really belies a lot of clean power here and I'm very happy. My only grope so far is for when using speaker wire instead of banana plugs, the holes to put the wire through at the back of the amp are very small, only a bit larger than the 16 gauge wire I'm using. Won't be an issue if you're using banana plugs, but do keep that in mind if you're using just the wire. So far I'm super happy with this little thing. Very impressive.
U**H
Great 2.1 speaker + sub solution
This speaker amp works very well. I connected 2x 6ohm 120w speakers, and a 130w sub and they sound great. SUMMARY: I had a 5.1 surround sound system (2010 model) but the receiver died. The speakers I had for it connected through the bare speaker wire pinch connectors (no banana plugs or RCA). This amp had the connections I needed for those speakers. I bought some banana plugs to go with it to make the setup easier (I would recommend this). I'm no audio expert so I can't tell you how this would work as a DIY amp for an audiophile setup or how amazing the audio quality is compared to other products on the market. I can tell you that this was just about the ONLY 2.1 amp I could find for the speaker and sub that I had. Build quality simple and is not flashy; but it's solid and looks as the picture shows. It doesn't heat up like my old receiver did. It is pretty small so that could either be great, or not so great--so you decide. It's about the size of my hand. I WOULD recommend this amp. With that said the quality of sound is good for me. I just needed 2 speakers and a sub for my PC and this amp powers them just fine. It's rated up to 200w and 12ohm. I listen to music and watch videos using speakers, but I play all my games using a headset. The system gets pretty dang loud and so does the sub. (obviously compared to 5.1 it's not as powerful). You get the idea of why I got this though. Read the instructions first before you hook it up to your power. This comes with an AC-DC converter (much like your laptops) that is rated for 19v DC. Needless to say there is a lot of power initially going to the capacitors. So connect it to the amp, then the wall. Not vice a versa.
D**N
Excellent value
I ordered this unit based on multiple positive YouTube reviews. It arrived same day from Amazon, and properly packaged. It took literally 5 minutes to set it up. It connected/ paired to my Motorola cell phone's Bluetooth with no problems. The sound quality streaming YouTube Music via Bluetooth is excellent. The sound quality playing CDs through the RCA physical connection is much better than I have ever obtained using my 2000s era giant tuner amps. The sound was further enhanced adding Micca MB42X Gen 2 bookshelf speakers, and an older Aiwa subwoofer. I bought this amp partly because it is so compact so I guess I shouldn't complain that as a result there is not much space for connections on the rear. There is minimal space between the outputs to connect passive speakers, you have to be extremely careful to avoid the cable ends touching the wrong terminal. I solved this with a small piece of insulation tape on each connector. The only thing I "miss" is having a remote for volume and source control. As you can probably tell from my description I'm not an audiophile, I honestly don't understand what half the audiophile reviewers are even talking about. However I've been buying consumer quality and better stereo equipment for 50 years and I appreciate the quality of the product and sound that this little amp-that-could represents.
E**C
Small
This is awesome. Very small. Great sound for my garage speakers. My only wish is that it would offer a version that also had AM/FM radio
K**A
Très satisfaite
Super top qualité
M**K
Amazing value for money
Excellent purchase , got it at very good deal price . Bluetooth works fast and perfect . Very easy to install and pair .
J**Z
Ehrlicher Verstärker
Überraschend guter Klang für den Preis. Der Verstärker klingt neutral, klar und ausgewogen, keine übertriebenen Effekte, sondern ehrlicher HiFi-Sound. Höhen sind sauber, Mitten natürlich, Bässe kontrolliert. Auch der Sub-Out funktioniert zuverlässig. Bluetooth-Pairing ging problemlos, Verarbeitung wirkt solide. Ideal für Schreibtisch-Setups oder Zweitanlagen. Ermüdet auch bei längerem Hören nicht. Klare Empfehlung für alle, die einen kompakten, ehrlichen Verstärker suchen.
P**N
Great Customer Service
I purchased this product about 18 months ago and recently it started having Bluetooth connection issues. I contacted the support team and we tried to diagnose what the problem is. Fosi eventually replaced the product under the warranty and shipment was quick. Thanks Fosi.
B**N
Way better than BT30D
Originally bought a bt30D which had almost zero power so I returned it. I needed something that would run two 6.5" full range speakers and this little unit does the trick. At only 50% volume this thing pounds. Highly recommend.
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