ARTPowerMIX III Three Channel Personal Stereo Mixer

I wanted a small, rugged stereo mixer that ran off a 12V power supply for a very specific purpose - mixing one mono (amateur radio) and two stereo (iPad, satellite radio) sources down to the single stereo aux input in my car. I was originally going to build one myself, but this little wonder seemed to fit the bill so exactly that I saved myself the effort and ordered it here. Glad I did - it works a treat in this application and is clearly rugged enough for automotive use (wish I could say the same about the satellite radio tuner - see separate review).I run the mixer and other electronics off a permanently-installed 12V DC-DC power supply to reduce noise and avoid voltage fluctuations in the automotive environment, and I wired my own power plug, but the unit would probably work fine straight off a 12V car adapter. If you want to run it off anything else other than the wall wart it comes with, though, pay careful attention to the power jack pinout! It is center negative, barrel positive, not the other way around. This may not be uncommon for audio gear, but it's definitely the less frequent convention in general, so a randomly-selected 12V supply, even if it has the right size plug, is likely to be the wrong polarity for this mixer.I like that plugging a jack into only the left side of a stereo input makes it a mono input (perfect to put my ham radio on the car's audio system). Since each input has its own level and pan control, I can easily "move", say, the ham radio to the passenger side, with the level turned down, and the iPad (navigation) to the driver side, while still enjoying a stereo program on the third input. Then if I hear a signal on the radio and want to join in, I can easily turn down the music and turn up the radio temporarily.Another thing I like: as a professional piece of gear, the mixer also can handle a high-level line input pretty well. I just connected the ham radio's speaker output to the input and as long as I keep the volume level on the radio reasonably low, it sounds fine. No need to make an attenuator.I'm not a pro musician and can't judge this mixer on that basis, but for my application, it's perfect!

I needed a device that would allow me to connect two computers to the same set of main speakers. I considered using some sort of speaker switch but when I decided on active powered monitors that ruled the speaker signal level switch out. The ARTcessories Power Mix III was a good match to my needs. Nice and small with front level controls and rear input jacks. Most of the tiny mixers like these have top mounted controls and inputs for use by a recording artist in a studio. The inputs are 1/4" mono inputs so you'll need cables like the  Hosa CMP159 Y Cable 1/8 Inch TRS to Dual 1/4 Inch TS Cable - 3 Foot  to connect the typical 1/8" stereo jack found in iPods and computer sound cards to the Power Mix III. The outputs are also 1/4" mono jacks which matched the inputs to my  Behringer TRUTH B2031A Active Monitor (Single)  inputs.In use the mixer is fairly well made with nice smooth controls and is quiet, it introduces no buzz or hum into the mix and there is no crackling when adjusting the volume. There are three independent source volume knobs that along with your computer's software volume can allow you to match the three sources. You'll want to keep the computer's software volume control fairly high to minimize the signal-to-noise radio - keeping the amplifiers fed with a good high signal so that the inherent noise they produce is lower in regards to the music. The master volume controls all three inputs at the same time. As others have mentioned even with all the volume controls down the signal is still not all the way muted and just a bit of sound is heard. Use the mute on your computer to kill the sound completely.There are two headphone jacks which are also the 1/4" size which is common in professional studio use. Most quality headphones come with an adapter which will work in a 1/4" jack. Plugging in the headphones does not mute the speakers outputs. There is a separate volume provided for the pair of headphone jacks.Power is supplied with a "wall wart" type transformer.Overall I'm very pleased with the mixer. Its well built with quality medal construction and the controls feel very smooth. I took one star away because of the minor issue with the volume controls not completely muting the audio.

I bought this for rehearsing, and have used it for a little over an hour at the time of this review. I like to mix my laptop with my instruments, so I can play along with backing tracks, etc. It works really well for this purpose. I don't plan to travel with it, but the metal case seems to be ruggedly built. The ability to pan the various channels made the stereo version of this mixer worth the extra cost for me. If you don't need stereo, consider the less expensive mono version from ART.The AC adapter has a flimsy cord, which is typical of many gadgets these days. This unit has some quirks, and for the money I'm a tiny bit disappointed. There is no on/off switch. I use it with a power strip that has a toggle switch so it's not the end of the world, just a little annoying. It also doesn't have a pad selector (-db) or a ground lift. No huge losses there, but would have been nice to have some of these obvious features. As another reviewer pointed out, even with all the volume pots turned all the way down, some audio signal still leaks through. Without a mute button on any of the channels, this might be a problem for some folks.Happily, I have not noticed any noise or humming from it and the sound quality is MUCH better than other cheap little personal mixers I have tried in the past from other manufacturers. Overall I'm satisfied with it so far, and plan to get a lot of use out of it.

Can be difficult to set up with multiple devices and get the sound balance correct.