Is it possible to connect a Mike to the "Aux In" jack on the MX61 using a Direct Box or a small mixer?

Hi! Thanks for the question.

The "AUX IN" on the MX49/MX61 is designed to accommodate a stereo input signal from a handheld audio playback device. It does not have the gain structure to boost a microphone's signal. It simply passes incoming signal to the analog outputs of the instrument. There is no analog-to-digital conversion, there is no mic preamp. (So, no, a microphone will not work, alone).

It is not the size of mixer that would matter, but the strength of the output signal. If you need to find out the exact specifications of that input you should email Customer Support- they maybe able to find the exact specification of the input. But in general, Input sensitivity is the strength signal that an input is looking to handle. Microphones are weakest of all signals (-60 ~ -50), and therefore require a preamp to boost their signal, a mixer typically can output signal at strengths considered "line" level (-10 ~ +4 or greater)... So that may be doable, but why?

You can anticipate that the Aux input is designed for handheld audio playback devices (read this as "consumer" devices - with 1/8" mini-stereo outputs); since there is no amplifier stage for this Aux In - all level control is handled by that external audio device. (The MX simply passes signal to the main output)... That is, it is NOT an interface for getting audio into the computer via USB... Like the MOXF, which has an A/D Input... So since you cannot combine signals to record to the computer, we're thinking you will require a different setup to optimize the situation.

The MX49/MX61's audio capability is as a 2-in/2-out audio interface...for itself. The 2 channels (stereo) are occupied by the 16 Part multi timbral tone generator of the MX itself... The MX has no ability to act as an audio interface for any external device, period.

The design concept is stated in the manual:

The Auxiliary Input stereo mini-jack is used to input audio from an external audio device. For example, you can use this jack to connect a portable music player and play along with your favorite music.

It saves you from having to use two additional inputs to your sound system when using an audio playback device... It combines your audio playback device with the analog audio output of the MX. Strictly convenient.

What is your application? What are you attempting to do?

When you find yourself adapting proper XLR, TRS, or TS jacks down to an 1/8" stereo mini-jack, you want Stop, look around, and get out of that situation. Look around for a completely different solution. Instead of using the MX as a mixer, get a proper mixer and let it combine the signals coming from the mic and from the MX... Let the mixer mix!
🙂

Recommended
If you wish to sing and play, a small format mixer with a stereo (line) input for your MX, and a separate channel for your microphone is highly recommended - Don't just pass signal, enhance it! The new Yamaha AG03 and AG06 meet the need and are professional grade audio mic preamps and will do the job of combining your signals with the type of control suitable for recording (to any type device including computers and iPads), sending to the Front-of-House or to your own sound system, or any requirement you may have. Mounts on a mic stand, bus powered or plug it in, +48v phantom power, etc.

If recording is not your goal, check out the Yamaha MG06X.

These are affordable, high quality solutions for audio (AG) and for mixing (MG). Hope that gives you an idea of the directions you can go.

Thanks, I did just that. Picked up a mixer and I'm working just fine. My thought was to get away with carrying as little as possible. But, since my mixer fits in my keyboard bag along with my Mike and cables, all is well. Thanks again for your responses and I just want to apologise for not responding earlier.

who's Mike?

I think you mean a mic or microphone.