Here's my question: What would be the recommended setup for the CP4 (playing acoustic piano sounds) in a large MONO "festival style" outdoor setup?

My personal recommendation is to have a situation where you can monitor yourself in stereo. The FOH guys will do what they do, they don't necessarily care as much about your comfort as an individual musician, they have a task to do sound for the house. Most find it easier to work in mono. Heck it's definitely easier, some take the easy way (every time). That's reality.

For me, if the band cannot hear themselves, they cannot play as a unit. If you can't hear yourself well, it will negatively affect your ability to play. I refuse to play in mono, not when I really want to play. I have my own monitoring system on stage and the house sound guy can take whatever they need off of that. The sound situation on stage should be designed so the performers are complete comfortable to play. For me that means stereo.

We've all done gigs where you can't hear yourself. If that was every night, I'd rather dig ditches! There is no worse feeling than not being comfortable. Make your stage situation comfortable! Whatever that means for you.

I'm with Bad Mister. I always run stereo for my monitor. If I send to FOH and they only have mono, then I send just the right side. [I find that the vast majority of stereo patches sound better taking one side than summing to mono. The most extreme example is a good Leslie sim. There are some cases that do sound better summed to mono; for these I make sure I know what I'm doing and when running mono to FOH I use a substitute mono patch, or skip them entirely. Rhodes stereo vibrato is a good example that doesn't work well either way, summed or just one side.]

However, a lot of players prefer to hear the sound the way it's going to FOH, and I can understand that. Plus a lot of them prefer mono in general, since it raises fewer issues and is easier to deal with. If you're going to run mono, then make sure you have a good set of patches that sound good in mono: use a mono piano, tweak the stereo patches so they sound good in mono (or just take the right side, but make sure you vet the patches.)

BTW, I find that the majority of smaller venues do run stereo these days, thanks to the prevalence of powered speakers. Most mixers are stereo, so it's just another snake return channel. For a typical small venue snake, that's two of 4 channels, leaving 2 for monitors. But outside and festivals do tend to be mono; I guess they're just keeping it simple.

But I have played mono venues. When they're small, I'll do something like, put one wedge behind me on a stool; the other vertical in front of the snare, and send the opposite side from that one to FOH. That way most of the folks in front and I get a nice stereo image. At the back of most small venues the sound is so confused by reflections it really doesn't matter whether it's mono or stereo anyway.

A very important thing to understand is whether your patches sum to mono well, if you're going to use the summed mono output. Fortunately, I find that CP4 pianos sum to mono quite well (though the mono samples are even better). Regardless, I use the right side as I think it sounds better than summed, and I like the stereo in my monitors.

If you prefer a mono-summed sound to send to FOH, you can use a DI box like Radial JDI that has a sum-to-mono feature (but you lose the 'thru' feature, IIRC.) I don't know why anyone would bother, though, after vetting their patches and comparing mono summed with one-side-only.

OK, This is great feedback. Thanks BM and Jeff for your responses

I am programming 2 sets of performances - 1 for stereo & 1 for mono.

For example: In one performance, I am using the 006 CFX Mn- voice with the default reverb & Damper Resonance effect. instead of the EQ, I added a CMP Classic Compressor effect for some extra punch.This is a performance for when I will be in a mono environment.

However, on the 006 CFX Mn- voice, neither the reverb nor the Damper Resonance are in mono! To get a true mono output I have to turn off reverb & Damper Resonance! Even REV Rich Plate & REV NPlate reverbs are in stereo which is strange to me. I thought plate reverbs on amps were inherently mono. What's the point of having Mn Piano voices if they aren't really mono?!

Maybe I'm overstating the sonic significance of this. Perhaps using a stereo reverb for an R channel mono output isn't that problematic. Or maybe there is a mono reverb and damper resonance effect that I haven't found yet? I'm monitoring on headphones so it is easy to hear any stereo spread at all.

Best case scenario - I use my group of stereo performances if the stage can support it. I currently use a Bose L1c for an amp, which sounds great most of the time. I mostly play house shows and small venues so small footprint is key. That's why i'm so obsessed with finding some good mono options.

You're right that it's not that problematic. When adjusting the reverb for your mono patch, just monitor it the same way you'll be using it live (that is, summed output, or one side.) Ditto for damper resonance, if you're going to tweak it, but I'd just use the default.

Most of the time, a stereo reverb is really just two mono reverbs, one for left channel and one for right channel, with slightly different parameter settings. It's interesting to see how little changes between left and right can build a rich stereo image. (The main exception to this, using two reverbs to make a stereo reverb, is "convolution" reverbs, which use linear modeling techniques to very accurately simulate a real room, based on "impulse response" recordings. These are true stereo reverbs, but still you can use just one side and it works fine.)

Interesting observation, in any case. I'll have to check it out next time my piano's set up at home.

I bet the CP4 sounds great through an L1. I bet it sounds REALLY great through two of them!

When I first got my C4 I was torn that it sounded so great in stereo, but not as great in mono -- for the same reasons as you -- many venus run mono on stage. As well, some small venues that I play by myself I only run a single Bose L1 Model II system. It took me a little while to dial in what I wanted for stage sounds in both situations.
After reading all of the comments about this, including the one (I think from BadMister) about how life is too short to run in mono, I decide to make some changes.

For my small venues with my single Bose tower - no monitors:
I programmed a group of sounds in my piano that were in Mono only. I mainly use piano sounds so this wasn't a big deal. I started front he Mono pianos provided and created one that sounded very "Grand" and another that sounded more like an "Upright". Tried it at a gig and couldn't be happier!.

For any venue that provides sound (with mono stage setup):
I find even though some venues run in Stereo Front of House, we still get a mono stage (which makes sense, why should the piano guy get two wedges).
I already ran a single Yorkville YX10p to supplement my piano coming back in the house monitors... It was always easier to turn up my little YX10p instead of bothering the sound tech for more of "me". ButI wasn't entirely happy because it was still in mono.
I bought a stereo DI so I could run a feed to my monitors and to the house equipment AND tried various 8" and 10" powered Monitors. (Some great music stores in my area let you take home and try before you buy).
It was between another Yorkville YX10p or a Yamaha StagePAS system. I wanted less wires/cables so long story short, I ended up buying another Yorkville YX10p. They're small so I can tuck them right in beside my piano or stool if need be and I run in Stereo all the time, and simply use the house monitor to hear the rest of the band.
If I share a monitor mix with another player I let them determine piano volume first and then supplement with my YX10ps. I have never been so happy with my stage sound.

Money-wise here in Canada, for two Yorkville YX10p's you're gonna pay around $399 each. You'd pay roughly the same if you went for the Yamaha wedges or maybe slightly less for a StagePASS system (which all sounded amazing with this piano.) I already had a 1 Yorkville YX10p so it made sense to just keep it and buy another.

I highly recommend running your own stereo stage monitors. You will not regret it and it's worth the extra setup time and $ if you can set yourself up this way.

My 2 cents.

KJ

This is great info. My practice setup is in mono, and the mono patches sound more natural than the summed stereo. I haven't tried it in stereo except in headphones.

In defense of sound guys, one good reason to use mono in many venues is that the stereo staging would be poor from the patrons' vantage point, so the extra speakers are used for coverage instead.