ICQUANZX 2x50W +100W 2.1 Channel Subwoofer Amplifier Board with Treble and Bass Control, Dual TPA3116 Chip, DC 12-24V, Bluetooth and AUX Inputs, DIY Wireless Speakers AMP Board

Zero regrets and totally recommended. First and foremost, I'm EXTREMELY impressed with sound quality. It reproduces stereo sound and has good separation between left and right channels. I love how there is very little in the circuit and I prefer a minimalist design. I feel digital signal processing and other features get in the way of accurate sound reproduction and don't use them anyway. I want to hear the music as it was designed to be played. I also listen at volumes between 25-50% which is plenty loud enough believe me. If you push volume to past approximately 60% you will start to hear diminishing returns in terms of sound quality, which is generally what I expect on any low-end equipment. There is no loudness adjustment, so you have to manage that using Bass and Treble knobs or though your device. No, it won't compete with audiophile amplifiers costing 100x more, but I honestly can't believe how good it sounds at this price point and small form factor. I hear no audible distortion while playing music or with volume turned up while music is paused. The unit needs to be assembled, which takes ~5 minutes, but it's not bad. I enjoyed the experience of putting it together because now I am more familiar with it and it's nice to save money due to the reduced assembly time at the factory. You should also know that this unit does not come with an AC adapter, so you will need to provide your own. I used an old 20V laptop charger that puts out 4.5 Amps, because I wanted to provide plenty of power with adequate headroom for the amp. If you don't have one lying around, just go to a thrift store or garage sale. With the adaptor unplugged, just cut the connector off, strip the wires, identify which is positive and negative with a multimeter, then use the provided phillips screwdriver to connect to the amplifier. The amp accepts 12v-24v DC, but naturally it will produce better power and sound quality with less distortion when you give it more voltage and decent amount of current. In any event, I connected all the wires and noted that the screw heads don't strip out when tightening down. I've had that happen before with other cheap products and wanted to point that out. The volume switch is different in that it clicks off when you turn it all the way down and the LED turns off too. When you turn it on the bluetooth connects automatically to your phone. No pin code or button to press. Not sure which version of BT is used, but seems to work well 20 ft away. Now for the sound. I have my amp connected to Denon home theater surround speakers which are not the most resolving, efficient, or musical; but I like them because they are relatively inexpensive, I had them already, they are very small, handle 100 watts RMS and are 6 ohm each, the midrange goes down to 60 hz, and they have soft dome tweeters so my ears don't get tired after listening for hours and hours. I set all knobs to minimum and gradually increased volume to find that it sounded flat with a ton of mids. This was expected, and I found that moving treble to 50% and bass 50%-100% sounds best. I'm repurposing an old Sony 5" unpowered 4 ohm subwoofer (power rating unknown) from a crappy home theater in a box I had lying around and it sounds best with frequency at 50%. I believe this equivalent to a crossover setting of around 80hz-110hz, but cannot tell for certain because there are no markings on the case. That's ok, I just used my ears for now and will adjust in the future as I get more time with this amp. I turned the subwoofer volume to 100% because I like a little bass and that sounded best with amp volume at 50% with the speakers I have. This amp blew me away. More than enough power to fill a room, especially if using desk or bookshelf speakers placed only a few feet away. I don't have testing equipment, but my ears tell me it is putting out very close to the rated wattage to the speakers and sub.

This amp sounds awesome. I think it's a step up from the Breeze Audio chip amps that everyone was using a few years ago, and the tone controls are a great addition. It does a great job of powering a subwoofer too, just make sure you give it enough power (I'm using an old Thinkpad 170w/20v power supply). It's a great amp.But this amp has the same achillies heel that most of these bluetooth-enabled amps have: it doesn't have a pairing button. That means if someone used it and is still paired (and in range) there's no way to force it to re-pair with your phone. It's easy enough to work around, just have people unpair, but it's been an issue for me again and again. Minus one star.And bizarrely, it stays paired even with the power turned off! That's a super weird one. I guess in some ways it's good since it forces people to remember to unpair, but still, it's clumsy. Minus another star.I wonder if there's some way to add a pairing button... I wouldn't be surprised if it's on the circuit board somewhere but they just didn't want to spend the extra $.30 to add the actual button.

This AMP is Boss is does as intended plays with equal controls of Bass Treble Frequency impedance same electrical Values !

Powerful amp with an off/on toggle knob. Good product with limitless versatility.