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

This amp is perfect for my listening habits. Plenty of power, nice clean signals, interfaces easily to my powered subwoofer. Plenty loud! Its footprint is so tiny, its amazing the sound it produces. And the price is less than $100. Would be great for a desktop sound system. Bluetooth is super easy and very strong. The unit cannot be controlled with a dedicated remote, which is sort of a downer, but if you're using Bluetooth predominantly -like me, your phone controls the sound, so no problem. You must supply your own cable for the subwoofer connection and for the speakers. Setup was a snap! If you have a small room for listening, this product will please you with a big sound for a small price.

I am very happy with this purchase, to the point where the product deserves a review! Build quality and appearance are excellent, sound is very good, and the price is right. NOTE: you NEED BANANA PLUGS. The little plastic screw tightener on the speaker lug strips, at least if you try to tighten it enough to have a decent connection of any kind. They're pretty but not very functional. NOTE2: get short, insulated banana plugs, the kind with a non-metal outer shaft, because they otherwise might tilt and touch each other. (see picture) The TPA3255 chip does *not* have short circuit protection, so you need to be extra careful! [edit] You want banana plugs with an insulating shell, heat shrink tubing, or just some electrical tape. See picture. The amazon basics and FosPower Deadbolt plugs are large enough to be almost touching, and although the shells are anodized, they're still metal. Anyway, you have been warned; just don't short out the connections! :) Application: I am using it with a pawn shop sub and a pair of old Radio Shack Optimus diecast aluminum speakers (the last descendant of the old Minimus speakers, basically they sound great but have zero bass). The sub is 4 ohms and supposedly handles 200W RMS (dual-6" speakers, really?) and the Optimus speakers nicely handle 50W RMS (8 ohms) but only if it's all midrange and treble. It's a bedroom stereo, so it's primary goal is to sound good quiet, but I do sometimes need to wake up. And I like bass. :D I bought the bundle with the 48v5A power supply, which because I have 8 ohm speakers and like to play music loud sometimes. :D Math suggests that ideally (and nothing is ideal), the power supply can deliver 240W to the whole system, and have enough voltage to drive the (4 ohm) subs to no more than 140W and the (8 ohm) tops to about 70W (RMS). In practice it seems to deliver. It's basically a perfect match for the 50W tops, while the sub surprisingly handles all of the supplied power until the amp runs out of headroom. (The sub channel distorts gracefully.) I have not attached a scope to see what the *actual* power output is, but AFAICT power is limited by the power supply voltage and speakers, not the amp itself, which is consistent with modern digital power amps. The whole system sounds good: as good as those speakers have ever sounded. :) The treble and bass controls are unintrusive, neutral at center-ish settings, and work. I wish the treble had a little more boost and cut, but I'll take "unintrusive" over "more boost" any day. The subwoofer has plenty of gain, and the frequency control has a smooth rolloff-- I used it to tame the peak at the top of the sub's frequency range a little. The system distorts gracefully when pushed. I primarily use bluetooth. This and the old technology of the speakers appears to be the only limiting factors for tone. A good system, would buy again.

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: Art If you found the review helpful, give me a thumbs up - Thanks!

Ho atteso prima di recensire proprio per completar un giudizio di performance più sicuro. Dunque posso testimoniare l’eccellenza dell’ampli della Fosi che fornisce un qualità molto buona. Un rapporto segnale rumore molto buono, una potenza ottima (spinge alla grande) e un buon controllo dei bassi ed alti. L’ascolto generalmente con sorgenti bluetooth e anche questo elemento ha una stabile connessione, pulita e di buona portata (distanza). Una nota sul surriscaldamento per uso esteso e a alta potenza: ho aggiunto una aletta di raffreddamento nella parte superiore che smaltisce molto ed evita potenziali blocchi. Nel complesso complimenti alla Fosi per lo standard qualitativo raggiunto !

I'm writing this review after using this amp with full attention...it outperform as per its size. delivers excellent sound quality. it is compatible with my bose acustimas 5 series III drive them without any problem. bluetooth connectivity is excellant i hand no problem to connect it to my samsung phone...it matians the slound quality too... people might be missusing the return policy or might not have read the specifications before buying

omdat je de totale controlé hebt over het geluid en hoge en lage tonen en zelfs de frequentie en volume van de subwoofer is deze model een van de beste, ik heb het zodanig aangepast dat ik zelf een centrale speaker kon installeren met een krachtige bose sub woofer . Het is zeker een aanrader ik heb eentje beneden voor mijn Tv en ik heb eentje boven in de geluid studio voor mijn Krk speakers prachtig geluid.

Compared to the BT30D non-Pro, the Pro version is quite a bit longer and heavier (430g vs 620g). The knobs are made of aluminium, different texture compared to the no-pro, a bit more resistance to turn than the. Same throw switch used to power on. The 3.5mm PRE OUT is full range. Bluetooth will be always-ON so your neighbor can hijack your device just like the non-pro version. Remove the antenna to prevent this from happening if you don’t use BT. Come on Fosi Audio, please fix this. The amp has a 4” tall BT antenna, again it's better than the 7” incher of the DA2120C that looks like a CB radio... Please give us the 1 incher for future products, for once the smaller the better. BT uses an ATS2853 chip that is also found on the BL20A. How does it sound? I did a comparison with Onkyo RZ50 pure output mode (airplay), Aiyima T9 (BT), and the BT30D non-Pro (BT). All using RP5000F towers, with an amp selector switch. Right away there’s a BIG difference between the non-Pro and the rest. The Pro version is much more dynamic, the voices are clearer, bass is more present and punch harder. I honestly cannot tell any audible difference between the RZ50 and the BT30D Pro. The T9 sounds only a tad warmer (thx lamp); Even that it was really hard to tell and it depends on the song being played. The Pro version sounds definitely better than the non-Pro. To test the passive sub output, I hooked up my gutted Z2300 logitech subwoofer, it works wonderfully and has a very capable output. However, I didn't like the sub crossover control, the adjustment doesn't feel linear. There are no frequency indications on the knob, it can only be tuned by ears. The muscle: TPA3255 x 2: PSU idle voltage: 32.3V Power adapter output @ 8ohm load current and voltage, 125W: Same 32V5A adapter used for multiple models. No sparks occurred while plugging in the DC plug compared to the DA2120C I've tested, I made multiple attempts to make sure this is repeatable. Here I am trying to figure out the max usable volume before getting a bad shaped sine wave, The volume knob is at 3 o'clock, BT reference volume maxed out on my mobile device, no EQ, no tone. L & R Channel, 8 Ohm load, 1000hz tone, 26Wrms per channel L & R Channel, 8 Ohm load, 1000hz tone, clipping at 60Wrms L & R Channel, 4 Ohm load, 1000hz tone, 40Wrms per channel L & R Channel, 4 Ohm load, 1000hz tone, clipping at 100Wrms Sub channel @ 4 Ohm load, 75Wrms: Sub channel @ 4 Ohm load into clipping, 121Wrms: Noise, tested with max volume: BT30D non-Pro, audible hiss from speakers during powerup, circuit shuts off when no input signal for 5 secs to prevent constant hissing. BT30D Pro, barely audible hiss from speakers, you have to stick your ear on the tweeter to hear it. no circuit to shut off the signal, it's not needed because it is not audible sitting away from speakers. The TPA3255 chips are hungry AND efficient. If you can feed them, they will put out a respectable amount of power for its size. You can upgrade to a 36V power adapter if you are looking to squeeze more juice out of it. It seems most of the manufacturers using this chip have set their bottleneck to the power adapter. If you are looking for a 2.1 amplifier with passive sub output, look no further. The BT30D Pro is way better than the non-Pro version. Pros: Great build quality Excellent sound quality, to my ear it’s on par with the Aiyima T9 and RZ50 Low noise floor Runs cool and efficient Cons: Cannot turn BT off Sub frequency needs indication and more linear tuning Smaller BT antenna please

He comprado este amplificador Fosi BT 30 D, al ver las especificaciones. Voy a dar mi opinión sobre este modelo en concreto. Este aparato es un poco mas grande que otros modelos, y lo bueno es que trae una fuente de alimentación de 48 Voltios. viene bien empaquetado en una espuma de alta densidad que lo protege de cualquier golpe. Para conectarlo he usado cable de 2,5 mm con unas bananas marca VCELINK, los altavoces tienen una P. 100W, 8 Ohmios, y una (SPL)de 90, Marca Celestion. El subwoofer es un Yamaha activo. El amplificador me a sorprendido que para lo pequeño que es tiene mucha potencia, suena muy bien, y no distorsiona para nada, para regular el subwoofer lo tienes que hacer con el oído, hasta encontrar el equilibrio para no escuchar vibraciones. Se conecta al bluetooth, rapidísimo, lo he tenido por mas de 4 horas seguidas funcionando a una potencia alta y no distorsiona ni pierde potencia, y tampoco se calienta en exceso. He probado otro modelo Fosi BL20C, y el sonido es mas cálido, y como su otro hermano, muy potente. Espero que os sirva de algo mis reseñas, me parece un buen producto con un precio decente.