The choice of a microphone depends heavily on the acoustics of the room or hall where you will be doing the shooting. If you are thinking of a single mono microphone for recording both performers at the same time, you would have to spend some time finding a position for the microphone that gives an acceptable balance between the two, given that the sounds that a voice and a piano each produces is so different.

Is there a possibility that you could consider separate microphones for the two sound sources and then mix them to a balanced final track in post production? Setting up different microphones for the voice and piano is likely to be much quicker and less tiring for the performers than spending the time to find a workable position for a single microphone. In addition, the types of microphone conventionally used are different for the two sound sources, so the acoustic result from a single microphone is unlikely to be optimal.

Perhaps the best one could imagine is recording in a concert hall (with or without audience), but where there is a good-sounding grand piano and decent hall acoustics. I have made passable last-minute recordings of piano and voice in these conditions with a single co-incident pair of small-diaphragm condenser microphones on a tall stand in front of but above the vocalist, aimed down roughly at the front edge of the piano. I was acutely aware that a carefully-planned multi-microphone recording would have been so much better.

To get back to your question, we would need to know a bit more about the situations you would record in, and also the purpose of the recording (archive, competition/examination entry, broadcast etc), and whether you are including the option of stereo recording.

Thank you so much for your reply, Boswell. I have learned a lot from it! I'm likely to be recording in a church (so a fairly resonant acoustic) and I'd be aiming to broadcast it on Youtube. I'll often be the singer, so it would be good to have a set-up that was straightforward for the performers and didn't require a lot of adjustment. Can you suggest a set up with two microphones that would work well in this setting? Do you think that stereo is essential? I have looked at Logic Pro as a DAW (as I use a Mac) but have been put off by the price. Do you have any suggestions for DAW?

Caz, post: 467738, member: 52504 wrote:
I'd be aiming to broadcast it on Youtube.

Doing lives to youtube require a good internet connection.. You should cover that too.

Easy setup, 2 mics ?
I'm my mind, it would be minimum 3 mics, stereo recording of the piano and mono recording of the vocal. What you want is the piano in stereo and the voice in the middle to make some seperation. In mono the voice and piano will be hard to mix in a distinc fashion and you'd be missing the superb ambiance a church can offer.. In this regard, you could add 2 more mics to pickup the natural reverb (put further away from the piano and voice.)
But in a church ? a piano, will it be an electronic piano instead ? that would be connected direct instead of using mics. (a stereo DI or 2 mono)

All in all, you will need an audio interface with 3 inputs minimum, a good set of head phones to premix the tracks for live streaming.
I don't see this as a simple setup for what you want to do..
If you'd let go of the realtime streaming idea, then it could be much simpler.. Get a zoom F4 or something similar, plug the mics, set the levels and you're fine.. You would need the F4, 3 mics and stands + cables and that's it !!

Caz, I've just looked up the specs for the Zoom Q4, and it has only a 1/8" stereo microphone jack input, not (as I was assuming) XLR connectors for professional-type microphones. That's not to say that the recorder's audio quality will not be up to the job, but it does mean that choosing a microphone with associated cables and stands to fit in your budget could be more of a problem.

One microphone that I sometimes use in this situation is the Rode NT4, which is a stereo microphone that can run from an internal battery when the recorder cannot provide appropriate power. The NT4 is supplied with both a dual XLR cable and also a 1/8" stereo plug cable for just this type of application. They are often available second-hand, but you should check that they are being sold with both cables and its case. Here's an example that does have the lot.

@Marco, I read this as a recording that will end up on YT, not live streaming. Caz, could you confirm this?

A decent common condenser microphone is the Shure SM57, which can be found on the internet for $75- $100. It's a real workhorse that can be used for tons of different applications. If you're doing audio and video, something like the Rode VideoMicro works quite well.

andrewjones, post: 467806, member: 52517 wrote:
A decent common condenser microphone is the Shure SM57, which can be found on the internet for $75- $100. It's a real workhorse that can be used for tons of different applications. If you're doing audio and video, something like the Rode VideoMicro works quite well.

Sorry but the SM57 is not a condenser but a dynamic mic.. completly different technologie.
With a good preamp it is true that it is a good mic for a lot of applications, specially if the room isn't treated and if the source can be very close to it. An alternative would be the SM 58 designed as a vocal mic.

pcrecord, post: 467810, member: 46460 wrote:
Sorry but the SM57 is not a condenser but a dynamic mic.. completly different technologie.
With a good preamp it is true that it is a good mic for a lot of applications, specially if the room isn't treated and if the source can be very close to it. An alternative would be the SM 58 designed as a vocal mic.

Thanks for your comments.

He never came back and told its the critical things - like where it will be recorded. In a beautiful sounding space - stereo to capture the sound sources and the space could be wonderful and just need two mics, or he could be recording in a rotten room, with a battered upright up against a wall and small hard wall surfaces and floor.

We can't really work without this info - but please - don't go down the Rode Video mic and SM57 route - what a dreadful combination for this project!