Fosi Audio Bluetooth Subwoofer Amplifier 2.1, BT30D Pro Subwoofer Amp with TPA3255 Chips 165W x2+350W & Bass Treble Control, 2.1 Channel Sub Amplifier for Desktop/Outdoor/Bookshelf Speakers

Big sound from a little box. I can't begin to express how impressed I am with this little guy. As a 70 and 80's HIFi buff that's use to twenty five to thirty pound amplifier's, I am stunned at what this little thing can do. It was as if this little Fosi Amplifier was made for my 30 year old Cambridge Soundworks Newton M80 speakers. My speakers shine.Pros: Light weight, and a very small foot print.Big clear sound with a big punch but no noticeable distortion.Has completely revived my computers sound system. Wow!!Very easy to hook up as you can hold it right in your hand as you connect the speakers.Outstanding Quality for such a fair price.Connecting speakers and my computer was easy and straight forward.Very easy Blu-Ray connection.Very fair price for what you get.Cons: Terrible Instructions if that's what you want to call them. I am getting very tired of the lack of instructions in all of today's products.No spec sheet of any kind.Could have had one more RCA in Jack.Enthusiastically recommended.

For context: I am an amateur DJ and use this amp as part of my home setup. It is connected to a Polk PSW10 subwoofer and two JBL C1Pro monitors with audio from my Denon MCX 8000 DJ controller.This is such a great quality amp for its price. It has exceeded every expectation I could have had.1. Audio is crystal clear, highs and mids are bright and lows are deep and powerful.2. Bluetooth instantly shows up on my devices list and stays connected with no disturbances when connected. There is no noticeable lag or delay.3. Control- it has knobs for volume, treble, bass, sub volume and sub frequency which are both on the actual sub.I 100% recommend this Bluetooth amplifier and would consider this to be the most affordable high quality amplifier on the market at this time.

EXTENSIVE testing trying to figure out "why" this great little amplifier didn't punch out the power. The subwoofer amp kept clicking off at higher volumes with the stock AC/DC 32v adapter. I ended up using a 12/24v to 36v step up booster and a 24v (10a) AC/DC adapter (Output is 36v, 10-amps). I tested the max current draw at full power - about 8.6 amps! The stock adapter is rated for 5 amps. Duh? That was the problem.This amp runs at 36v all day long...and a little warm. But, if you want full power and not having the subwoofer amplifier chip kicking off all the time -- either get a 32v (10-amp) adapter or even better 36v (10-amp) adapter. The good thing, a simple turn off/turn on resets the amp (subwoofer amp will reset).The Bluetooth 5.0 is phenomenal...excellent and fast connectivity.The fidelity and sound quality is totally quiet and pure. THD ratings are probably dead on accurate. It really plays beautifully all the way up to full power.The pre-amp out 3.5mm jack is a brilliant addition -- I tested it and it works like vintage equipment. Bluetooth connectivity is not affected. Linear with mains. If you ever wanted to add an active sub via this jack, you can -- it is full range.AUX input works -- no issues with low power pre-amp section like many other of these little digital chip amps. Bluetooth 5.0 is set HIGHER than expected -- NICE job Fosi! So many are set too low.Use banana connectors for your speaker wiring -- 4-8 ohm for mains, 4-ohms plays best.BOTTOM LINE - feed this little guy 36v and 10-amps of power and it is one helluva performer. It will deliver some nice subwoofer bass if your subs are decently efficient. PA sub cabs @ 4-ohms work best. Car subs are not that efficient (low SPL per watt). For those just wanting a lower volume 2.1 home AV system (like for watching TV or on a computer), no need to upgrade the included AC/DC adapter. For me, why by a Corvette and drive it like grocery getter Camry?

So for people reading this thinking why the glowing review, let me tell you first what my main system is. My speakers are B&W Nautilus 804’s with Nautilus 800 HTM 1 center, 805 surrounds and SVS height speakers for Dolby Atmos powered by a Denon AVR-X4700H. This amp and speakers in no way compares nor could it.For my computer, I bought a Cambridge Soundworks package containing The BassCube 821 and the MC 105 speakers about 13+ years ago. The BassCube has a down firing 6.5” polypropylene woofer (4 ohm) in a sealed box that also contained the amplifier for the three speaker system. The MC 105 (8 ohm) has a 1” aluminum dome tweeter with a 3” midrange in a sealed cabinet. The system was similar in design and appearance to the Klipsch ProMedia 2.1. Unfortunately, my system finally failed after years of service leaving me searching for a suitable replacement for that particular location and purpose. What failed was the amplifier that powered all 3 speakers. The power supply filter caps failed taking out components down line – not worth fixing.I considered the Klipsch ProMedia 2.1 but the long wait time and some reviews mentioning early failures and sound issues made me hesitant. My next choice was the Edifier S350DB which is larger than the Klipsch and my Cambridge system and it too had it’s detractors and is $400. So, I tried the Fosi Audio Bluetooth Subwoofer Amplifier 2.1, BT30D Pro and was blown away by the sound. Connecting it to the MC 105’s was easy as I just needed good speaker cable with with banana plugs at one end for the amp and twisted wire for the speakers. The 6.5” subwoofer speaker I connected internally directly to the existing speaker terminals. I first removed the wires from the internal amp and used two of the four speaker terminals on the back to connect the woofer to the sub input on the Fosi. Then I put all the screws back into the back panel of the subwoofer to close it making a good air tight seal.Previously, the bass coming from the BassCube 821 when it worked was boomy at times and sloppy it wasn’t tight and certainly didn’t go deep. Now it feels tightly controlled, musical and it goes way deeper. It seems to have more synergy with the MC 105’s which also sound more musical to the point that I actually listen to music while working on the computer instead of watching TV. Your mileage may vary based on the speakers you use but at this price point for me at least it was worth the try and I am amazed/surprised at the audible results. The amp has just the right settings to tailor the sound to your speakers and preference. The separate Bass and Treble are mainly for the smaller speakers and have little effect on the subwoofer. For the sub you have SUB FREQ which sets the cutoff point from deep bass going clockwise on up and SUB VOL which together give the ability to tailor the sound to your liking.I bought a power strip that turns on the monitor and the amp when the computer powers up so I don’t have switch it on and off, the TrickleStar TS1104 7 Outlet APS, 1080 Joules, 3 ft Cord White sold on Amazon https://www.amazon.com/TrickleStar-TS1104-Outlet-1080-Joules/dp/B0B61ZCPK6.Now when I turn on the computer everything turns on by itself, the amp and the monitor.So if you have a dead Cambridge or Klipsch system and are handy with a soldering iron or if you have speakers you really like but their current amplification is not so great, give these a try, you might be pleasantly surprised.BTW, I have received nothing in return for this review.All the best:ArtIf you found the review helpful, give me a thumbs up - Thanks!