I know that there some situations where a mixer is needed, but if volume is the only question, is one needed? In other words, let's say your instrument sliders are at max and you need more headroom. The obvious answer is to increase the speaker volume and back off the sliders.

Or, am I missing something? If I have enough channels, my eq,FX, and pan are fine, why do I need to lug a mixer?

Bernie some good info on Pre Amps in a mixer benefits

http://www.ovnilab.com/articles/preamp.shtml

Donny artical is great info. And number one on your list, yes ,a mixer will give you more headroom by boosting the keyboards output. ANd the other benefits mentioned there. But you do have another piece to move and setup.
For myself one of the reasons I love the BK9 is that I don't need a mixer. As you know it has a mic input and AUX input for my IPad so all I need to do is plug the BK9 into my powered speakers. I've never put my master volume on the keyboard past 12 and never past 2 o'clock on my speakers. Plenty of headroom.
"Could you turn down, we want to talk" LOL

Good reading Donny. I see it is not a cut and dried situation, given the variables. I have several mixers, but my small one is a Yamaha like yours. If you didn't need extra channels, would you bring yours? I think you always do.

Hi Bill
For the reasons you give, my Audya and pa4X wouldn't need one.I am not sure about the S970. I think I have to give it an AB test myself.

Thanks

Bernie my two cents.
The more stuff I have the more I have to carry. But even more important, the more equipment I am using the more I have to be concerned with. There is no doubt about how a preamp can add to your sound. They use them color the sounds before it is amplified.

At one time I was using a mixer, a BBE sound maximizer, and an EQ. besides the instrument volume controls and EQ. With your equipment nothing is needed but a good microphone. (My opinion)
Your new korg keyboard has volume controls and EQs for the instrument and voice. They created a keyboard that does it all.

If you had thoughts about adding another piece of equipment, or more microphones, that changes the story.

Hope this helps, John C.

Don't need no stinkin' mixer any more. But I use one most of the time anyway, just in case I have a guest artist or vocalist. Also I could, along with laptop, could get through the night if the keyboard ever failed.
I use this one these days. It is powered by USB, weighs next to nothing and has outstanding features.
http://usa.yamaha.com/products/music-production/interfaces/ag/ag06/

I also have a larger Yamaha mixer, MG82CX, and an even larger Peavey, PV10, for the increasingly rare events where I need them.

The only thing a mixer really does is allow you to mix the outputs of various devices - mics, etc... The output is essentially a line out voltage, just the same as your keyboard. The volume control does not really increase that output voltage, however, it does allow you to vary it from low to maximum line output level.

I sold all my mixers, mainly because I no longer play with a band and have bandmates plugging into the mixer with their instruments. I plug my mic into a TC Helicon Harmony-M and the output of the TC goes into the mic/line in of the keyboard, which is set to mic. Yes, the TC output voltage is line voltage as well.

I have never measured the output level of my keyboards, but I have measured the output voltage of my mixers. They were all at line level, which is 1-volt RMS.

Gary

Thank you one and all.

I think I can infer by expert advice given, that as long as the signal strength is sufficient, and additional mixer inputs not needed, I could leave the mixer home and adjust volumes with the keyboard and speaker.
p.s.
Just to be safe, I always have one in the van if needed.

I love mixers because they give me more control in overal sound. I usually get the best mixer I can afford.