Little Bear MC5 Mini Portable Stereo 4 Channel Audio Mixer Passive Live Studio Console Recording Low Noise (No Power Needed)

This little jewel box is a passive stereo line mixer. The inputs are adjustable in impedance with tiny switches. There is no external power supply required, instead, this design steals power from the sources and the amp it's plugged into. The designers have delivered a unique and fairly priced device. Today I'm using it with a Headrush GO amplified stereo speaker which only has one TRS line input, this little mixer let me plug in guitar amp modelers by Line6 and Mooer modeler plus a little drum machine, all battery powered - it's our portable, miniature, jam rig for my wife and I - to use when the power goes out. The little mixer has no metal enclosure - it's basically a stack of thick PC Boards - you'll want to keep it away from big noise sources (not hard using an all battery powered rig). In spite of there being no metal or plastic enclosure the small size of this mixer makes it a joy to use anywhere and it is surprisingly low in noise.This little mixer has quickly become a favorite due to no-power-required and the four inputs, not to mention every input has its own volume control and there is an adjustable master output level. If the price goes up then there is competition but at the current price nothing touches the BEAR, grab one of these while you can (if you're an audio geek like I am). GOOD MUSIC TO YOU!

This is a great little passive mixer and perfect for my application, which was feeding audio from computers and keyboard instruments into my monitors.It cuts the volume by about 6dB (I didn't measure it.) So you can't use it unless you have enough headroom to boost the volume. For most line-level devices, that shouldn't be a problem. If you're always running your gear with all the knobs at 10, this will not do for you.I don't detect any added noise, but of course the S/N ratio will go down, by 3 to 6 dB. It's not in a shielded box (which is obvious from the pictures) so isn't advised for a very electrically noisy environment. Don't set it right next to an old CRT display or a motor. Modern gear when used correctly has a high enough S/N ratio that it shouldn't be noticeable even to golden ears.They should definitely fix the description that says it won't reduce the signal level. A passive mixer HAS to reduce the signal level. Without the resistors (or replacing them with 1-ohm resistors), you're just tying outputs together, which is bad for the outputs, and affects the quality of the audio. Replacing the resistors is a really bad idea. Don't take my word for it, ask any EE.Active mixers (ones that don't reduce the volume) are built by putting an op amp behind a passive mixer, to boost the signal just enough to restore the lost volume. If you can't turn your gear up louder than you need, you need a "line mixer" not a "passive mixer". It won't be so tiny and will require power.

Does it work? Yes, it does. If you are using headphones with no phantom power, all volumes have to be completely maxed out. This would be perfect for a younger person because it's certainly loud enough to hear but will not be loud enough to hurt a kids ears. All in all, it's good enough to use when messing around and the small form factor is nice and matched the fact the Volcas are small. I don't love it, don't hate it. It serves a purpose at times.

My use case is probably different from many others. I am into retro-computing and listening to mods on my Amiga while drawing. However, due to the full stereo separation of the Amiga's audio channels listening on headphones was very intense. Ms. MadLemon on YouTube made a device to be able to adjust the mix the L/R channels to soften the experience. I thought, there must be a way to do this without building something. (Not that I couldn't build it I just don't want to at this point.) My first approach was to use PulseEffects on my PC with the Amiga connected to the line in. I made a loopback device with 1ms delay so the Amiga would play through mixed with the PC audio and then adjusted settings in PulseEffects until I got the desired result. This works great except for when I plug in another device that has audio capabilities - then everything "auto-magically" switches to the new device on Linux Mint. After some searching I for a very basic audio mixer I hit on the Little Bear MC5... and I thought and thought about it for a couple of months due to the negative reviews. Finally, I pulled the trigger and got it the other day. I made a short 3.5mm L/R crossover cable to reverse the channels. I plugged the Amiga directly into input 1 and then split and reversed signals into input 2. With input 1 at 100% and input 2 at 75% I get just the right blending of the left and right audio. Better still, my PC goes into input 3 now and I have another one open for one more device on the desk if I am testing. PulseEffects and the loopback aren't needed anymore so I am pretty happy!Pros:Small - Doesn't eat up desk space.Modestly priced.Passive - no extra USB or power cables.Good weight and solid build.I don't detect any added noise through my powered speakers or headphones even when crank the volume on the speakers. (Bose Companion 2 series III speakers also drive the headphones.)Cons:None that I can see.Other thoughts:Now that I have it I would like a version that has a small integrated amp. (Or an add on amp with extended case screws in the same form factor as the MC5 that you can attach to the MC5 and keep it all one package.)I knew this was passive and would not boost the audio. That is NOT the issue. The issue is that I forgot that PulseEffects was boosting the gain from the Amiga's input and the PC's normal sound. This drives the blinking lights on my Sony SEQ-430. Without that amplification the spectrum analyzer can only move on the strongest sounds. Not a huge deal but now it has me thinking about a headphone amp to put inline.