Douk Audio M4 HiFi Bluetooth 5.0 Digital Power Amplifier Stereo 2/4 Channel Audio Amp 50W x 4

Nice, affordable alternative to an expensive setup. Great for a DIY speaker setup with BT.

使用方法は用途とは違いますが、４スピーカーそれぞれ音量調整をしたかった。 アレクサでラジオを受信し、各部屋の広さに合わせて音量をコントロールしてます。 モノラルの音源になってしまいますが

Shipping and delivery from Douk Audio very fast and painless. I'm using this to drive bass shakers on a Sim Rig. I was uncertain about the connector as this isn't (or doesn't seem to be; the feature descriptions are ambiguous) a USB sound card, but it installed easily and perfectly as a Bluetooth audio device which turns out to be much easier than yet another USB connection on the rig. The build quality is really impressive at the price and it works well and feels very robust. I was using the other well-known and popular brand cheap little USB 2x50W solution - had no problems for a year then mine failed and its replacement failed for no clear reason. This solved the problem and has given me the extra channels to add a couple more shakers when budget allows.

This amp is an absolute beast! I'm using it in my 1600 sq ft shop with 4 speakers mounted in each corner, and let me tell you - it will absolutely rock the entire place out! The power this thing puts out is seriously impressive. One of my favorite features is being able to adjust each channel's volume individually. This gives me perfect control to balance all four corners of the shop and get even coverage throughout the space. The Bluetooth range is surprisingly good too - I can move around the entire shop without any dropouts, which is exactly what I need when I'm working. I've been running it with 2-ohm speakers and it handles them beautifully at around 75% volume with no distortion or heat issues. Plenty of headroom for when I really want to crank it up! There are a couple of small quirks worth mentioning. The speaker wire terminals are a bit finicky to work with - they get the job done but aren't the most elegant design. Also, the channel numbering is counterintuitive with channel 1 on the right and channel 4 on the left, rather than going left to right as you'd expect. You get used to it quickly though. Despite these minor issues, this amp is perfect for my shop setup. The power, flexibility, and wireless performance are exactly what I needed. Highly recommended for workshop or garage setups!

This is a great 4 channel amp. Have installed 2 at my son's who moved in to a house w/ 3 sets of built in stereo speakers and I added my large indoor 12" woofer, mid, tweeter to his living room. So, 8 channels driven. Not using Aux In. Selected Ch3&4 RCA's for Output and fed the second M4. Have 2 at my son in law's house. Same as son's he has 4 Stereo sets that came with the house. There I took his Flat panel TV output and fed the Aux RCA's in for Ch1&2, and selected Ch3&4 RCA's for Output and fed the second M4. Installed 1 in my garage driving indoor and outdoor Bose wall mounts. Bluetooth works great w/ good range. Big bonus for me is the USB. I took my old USB-2 thumb drives and copied genres or "playlists" to a bunch of them. This really is my favorite use. Plug in what I want and crank it up! This is a 4 channel amp, so each speaker has separate volume. Plenty of power. Works for me. Oddities: Looking at the front, the Channels volumes are Ch4, 3, 2, 1 left to right. Being an old time audio guy, Left is Ch1, Right is Ch2 for Stereo. I just wired it so Ch1/3 is my L, Ch2/4 my R. On the Aux input, just hook Source Red to White input, White to Red input. No big deal. Wishlist: USB has Next, Previous & Pause/Play buttons. Would love to see Next & Previous "album" and Shuffle. Update on USB use: It is a bit fussy on the thumb drive you use. Data Travelers work. Patriots USB-2 did not. PNY USB-2 no, USB-3 yes. I just bought a 10 pack of PNY 32GB USB-3.0's that work great. Cheap