Line Mixer 4 Channel, Donner Low-Noise Mini Audio Mixer DC 12V with AC adapter & Stereo/Mono Adjustment, As Microphones, Guitars, Keyboards or Stage Sub Mixer, Ideal for Small Clubs or Bars

So far the Donner DEL-812 is a win for me! Just had it a few days, but for the most part has solved my recording issues So far.I record music on PC, and my audio interface does not feature 'direct monitoring'. This means you can only 'record monitor' using the DAW software. When recording guitar or bass, there is a latency delay when you record monitor thru the DAW. Enough that it affects your playing, and the accuracy of the recorded tracks.I have a new audio interface on backorder for months, so this mixer seemed like a possible workaround for the current interface. I have the audio from the interface in stereo connected to input 1/2, and the guitar signal splits (1 side goes to the interface, other goes to input 7/8) And......it works! No delay monitoring the guitar tracks, I can still record and playback in the DAW, in stereo. The guitar signal is panned totally left, or if you push the mono switch, it's centered. No more latency delay, accuracy is now possible again.Pros:*No noise! None. I have all kinds of amps and pedals, PC, interface all connected here and there, this mixer has zero noise. I didn't need the ground lift switch.* It's loud! Super loud when using headphones. I have everything set at around 2, and it's plenty loud at 2.Just beware it does pop when you turn it on, could hurt...* All metal, sturdy construction.Cons/Problems:* Wish it had a pan control! So you could control how where the signals are in the headphones L/R.With standard TS cable, the guitar is either all the way completely left, in dead center with the mono switch engaged.* Stereo/mono weirdness: When I first hooked it up I was trying all kinds of plugs, and different sources, and some of the stereo sources were outputting in mono. This went on for a while until I turned the power off/on, and stereo tracks returned, back in stereo. Only think I can think of is the internal mixing chip gets confused between mono and stereo when you're plugging and unplugging different sources. (Some mono, some stereo) Anyway, if this happens, try turning it off and back on. Hasn't happened again since then.Overall, nice little super basic mixer!

At approximately 4.5 inches wide x 3 inches deep, the Donner DEL-8i2 is the perfect size to conveniently place a sub-mixer in easy reach from your keyboard or guitar stage rig. The unit has 4 stereo 1/4" inputs. Two of the inputs can be switched mono/stereo. While most professional keyboards and sound modules have two line outputs to run stereo, an inexpensive stereo/mono Y adapter will work for each input. Setup and control is simple with 4 well-marked volume knobs on the top of the mixer and two 1/4" line outs. The blue-lit power button is bright enough to see on stage but thankfully not annoyingly bright as some can be.The mixer sounded clean and would work well if you were submixing to an amp or into another mixer that has limited available channels, which is the case I often find when playing multiple keyboards in a large band. The mixer is externally powered by what appears to be a standard adapter. The only challenge I saw is that the adapter power cord is 4 feet long, which is long enough to plug into a power strip if you play keys sitting down, but I perform standing up. It's a challenge that can be easily resolved and definitely not a deal breaker.For the price, solid quality, simple use and convenience I'd definitely recommend this as a great little device to have in your gig bag.

Purchased one during early 2021 so this is somewhat a long-term use review. I use this line mixer to mix audio from my game consoles and computer. There could be revisions to the mixer as my unit still has the misspelled "LIFT" on the output label. It looks like they've corrected it to "LEFT" in the newer ones.TLDR: Solid compact build and will work well for most use cases. Volume knobs can be scratchy when adjusting volume, and there is a popping sound in your headphone/speakers when turning the mixer on. Slight channel imbalance at lower volumes can be a problem for sensitive IEMs. The included 1/4 inch adapters are bad. I had to purchase new ones.Pros:-Solid metal body. Feels weighty but it is still compact.-4 stereo inputs is great at this price.-Stereo sound works great (at certain volumes*) and I do not notice any noise floor during my use case.-Dedicated power button. Some alternative cheap mixers don't include one.-This is more so a personal preference. I needed a mixer that had the output in the front with the power button. The inputs would need to be in the back too. This is just to help organize the cable clutter and make it easier to plug things in and out of the output.Cons:-Included 1/4 inch adapters are bad. If you find that you are hearing noise while using the mixer, it could be the adapters causing it. New ones fixed it in my use case.-Volume knob makes a scratching noise in your mix while adjusting. I find that muting/pausing the audio before adjusting helps alleviate it.-There is a popping sound in your headphones/speakers when turning the unit on. I believe this is normal as the power goes into the mixer. It would be nice if the output was cut off during the first 5-10 seconds to help alleviate it but at this price, I can't really fault them for it. I just make sure my outputs are not plugged in before turning it on, and give it a few seconds to "warm up" after turning it on.-*Channel imbalance at lower volumes in the volume knob. This isn't really a problem unless you're listening with something sensitive like an IEM. If your input device does not have a way to control volume, then this could be a problem for you. In my unit the channel imbalance is around the 7 - 8 o'clock position of the knob. I usually keep it at around 9 - 10 o'clock to avoid it.-This may be a con to some people. It uses a barrel jack instead of USB C to power it. The power adapter is also a bit chonky at the end so you might have trouble plugging it into a power strip.-Maybe a con also to some. The power button has a bright blue light when turned on. You can't turn off the light and would have to block it with tape, but you'd be covering the button too.Things I'd love to see in a future model:-Mute buttons for each input would be nice. Maybe make it a different model dedicated to desk use. With the ground/floating and stereo/mono features, I assume this unit is catered more so towards musicians, artists, and audio engineers.-Eliminate the popping noise when turning the unit on.-Low/High gain switch for output. Channel imbalance problems with sensitive IEMs can be solved this way.-A master volume knob for adjusting all the inputs at once. Maybe this could be an alternative to a Low/High gain switch. A mute button for this master volume would be nice too.-USB C power.-Better 1/4 inch adapters would be nice. Maybe mine were bad luck. In that case, better quality control.-I don't really need this but maybe some might find it useful. 2 outputs with a button for switching between them. Could be useful for people who use headphones and monitors/speakers at their desk. It'd be important to have the gain levels be different for that use case since it would be pretty dangerous to go from high volumes on a speaker to headphones. Maybe separate master volume knobs for each output would work.