Rolls MX41b Four Channel Mixer

It's well built and solid. I've had mine for going on a decade. No worse for the year. But what is it for? Well, it's a fancy unpowered audio splitter and/or mixer. I use mine to take one sound output from my computer and control 2 sets of speakers, a bluetooth transmitter, and/or headphones.But the sound loss (attenuation, I see it's called) is real. Well, here's what I've figured out: any signal that goes between any of the channels is cut down to a low but consistent level. There's no power plug, right? That's a plus. But what goes in, sound wise, is all that can come out. And though what comes out is *less* sound output, it is also *consistent* sound output. And that's not bad. Moving the sliders or plugging and unplugging things doesn't change the volume on the other channels at all, as it would if you used a simple cable audio splitter (at a fraction of the price). Here, the output is constant (though always low) no matter what you do.As to the extent of the sound less, if I plug my headphones into my computer, I might have the computer volume set at 17%. If I run my headphones through this and set the slider to max, the headphone volume is lower even when the computer volume is set to 100%! That's a big difference. As another review says, takes the cons seriously. But if you connect to anything that is powered (as in, you plug it in) and amplifies the sound you're fine. But the sound loss is large enough that it does not work well with anything that doesn't have its own power supply, which probably means headphones or little self-powered speakers. At least not with any output I can get from my computer.Here is my headphone workaround: Each channel has two sockets, one 1/4" and one 1/8". Plug the headphones into the same channel as the input signal. Then you get full volume (albeit without slider volume control). Sure, you could plug your headphones directly into your computer, but for whatever reason (distance, convenience, or lack of multiple audio outputs) you bought this so you don't have to.There are five independent audio channels, four with a slider control and a fifth on the back. Since the mixer can be used in either or all directions -- and this is where things get fun -- you can use the 10 sockets in almost any input/output combination you want. 6 inputs and 4 outputs or 1 inputs and 9 outputs. You're only limited by the fact the sockets are paired (and different sizes) and there are only 4 volume sliders. And also by the fact that signals coming out will be weaker (much weaker) than the signal coming in.

Little to no noise great utility mixer, use to allow 4. Stereo mixes to a single amp. Amazingly simple rugged and useful.

I have two of these that I use to run audio from echo dots and PC's to single sets of speakers

Use it for my Bose s1 when I need an extra input. It’s simple, well built and does the job.

It's good. Yes you loss a lot of volume but just plug it onto an amp.