It's jazz, you can play almost anything you want...

You have to know the rules before you can break them. When playing with others, you have to be able to play the changes before you can start making chord substitutions. By the way, there are a lot of incorrect changes in the Real Book.

My question is: how well do you know these songs and their changes?

 

"Jazz"?

Which "jazz"?

In my trad group, don't you be playing those Giant Steps substitutions in "Sweet Sue".

In my bebop group, you'll have more freedom to make chord substitutions and apply different tones over a given chord, but there are still lots of note choices that do not sound good. Yes, it is possible to play any note over any chord, but where and how and what goes before it and what goes after will drive whether it's an acceptable note choice. If you don't get that stuff right, it is not a correct note.

Even in free jazz you cannot "just play anything".

That bit about "you can just play anything you want, it's jazz" typically comes from people who have inadequate knowledge of the forms and practices of the music we call "jazz". It also is generally said by people who sound bad when they attempt to play the music we call "jazz"; and instead of learning how to play the music, they hide behind this supposed theory that you can 'play anything". No, if it sounds bad, it's wrong.

 

My opinion, if you hear it, play it. If you don’t hear it don’t play it. If the music is not in your head than it is not likely to come out by forcing some patterns, scales, or iiVI riffs. Kind of takes away the concept of right and wrong notes. For inspiration try listening to the other folks you are playing with, or even more fun, let the audience influence what you hear.

 

When the situation calls for it, I thoroughly enjoy inviting "enthusiastic Jazz-bashers" to come over and bring their axe to a "jam-session".

Unbeknownst to them playing changes are the most definite norm at said "jam-session".

The establishment where the "jam-session" is being hosted is quite popular and it looks very inviting from the outside and warm from the inside.

The look on the face of the "Jazz-basher" looks somewhat grim when he or she enters the establishment and the further we go into the evening the "Jazz-basher" seems to be not talkative anymore.

"A musician should be able to play anything when the situations calls for it."
-Grant Green

 

The statement isn't wrong, but, like all "freedoms" your peers will judge you on how interesting your results are.
What isn't really discussed is how all western music has sections of connecting and disconnecting from vertical harmony - in the "disconnected" sections your line still needs melodic interest to work. There is very little music that is a solid block of sound with melody and harmony at the same dynamic for an entire composition.
Jazz pushes these ideas even further - the term "changes" literally means meeting the moment the chord changes. In between changes you do have more melodic freedom than most music but it does need to hang together and hit that meeting point. For jazz.

If being "free" means checking out and not paying attention, then it won't get you very far. If being free means listening for multiple logic systems but being in the moment and trying to stay connected to all the musicians you are playing with, you likely have more leeway than you might think.

 

If you are not All one the same page, it's Experimental!

 

Sure, you can play whatever you want. And if you don’t know what you’re doing it will probably sound like it.

 

Also, it is a very true statement in relation to most "rock" music.
A true but embarrassing story:
There was period where I was playing the most jazz I'd ever played - I was walking through changes everyday with a horn player and even playing the odd restaurant gig. I was also playing a ton of free jazz and improvised music. I got called to do the soundtrack for Werner Herzog's "Grizzly Man" - and I had truly lost touch with basic rock playing and hitting the root on 1 with a back beat! I could hit the root on the 1, but wasn't much use the rest of the bar at first! I worked it out, but I struggled and I've respected the precision it takes to play that stuff ever since.
You have FAR more leeway even in the most harmonically literal jazz than the most basic rock.
It all depends on your perspective.

*I got my licks in by proposing music for the bear fight, which Werner wasn't going use music for and he used a bit of the duo the 'cellist and I did, and nice arco duo with Richard Thompson. Still, it was an embarrassing and high profile situation to find out what playing jazz DOESN'T give you!
I also got a quick lesson in how disorienting it can be the play the double bass with headphones on that same day. I got a second chance on "Encounters at the End of the World", where I showed up more prepared and assertive.

 

There is a lot of good thing being mentioned.

I feel like I am going to be the party pooper, but enjoy jamming with these people for what it is worth. Don't try to change them if they are not open to it.

If you really want to play with the real book, find people that want to do so.
I could say a lot of things but I'm not sure it is worth for that situation. Just enjoy it!

 

The Real Book or not question shouldn't really be under discussion here. It is about playing jazz and changes, and what you can play on them or not.
Once the changes are agreed upon, then those are the changes. Whether from the Real book, a recording or a chart directly from the composer.

 

Also, tracking down historically "correct" changes when a person can't navigate a II-V-I or keep a 32 bar form is a massive waste of time.
The Real Book is great place to start learning the basics - that is one of the best uses of it. It is more than a fine place for the players the OP is playing with.

 

Find another KB.

 

I think it very important to be able to play without a real book. Your best stuff, in my experience, does not happen with you head in a book. A useful tool to learn toons and, in my opinion, a hinderance to using your ear and going where the music goes,