I have Sonar X3 Producer. I don't get an opportunity to use it as much as I'd like so forgive me if this is an obvious question.
 
I realize Sonar is for music production. But how useful is it for a musician wanting to learn how to play a song note for note? For example, does it have any features for chord/note detection? 
 

AFAIK, Not really at least in real time. Not sure if the Sonar  chord analyzer even made it past X2, but this shows what MIDI chord is played.
For keyboards, there are various 3rd party plugs and programs.
For guitar I suggest Jam Origin for guitar to MIDI then into a chord analyzer.
For a standalone guitar learning app, look at Rocksmith.

Thanks for quick response. I'm a keyboard player. In several bands that mostly play covers. Not necessarily looking for real time detection. My ear isn't as trained as I would like it to be and I need a little help sometimes. Just something to help me break a song down better. I use cordec on the iphone to slow a song down so I can find the notes in some lead, or see the chords. I've used band-in-a-box for cord detection.  But I figured if sonar had this capability they'd probably do it better. If you know of any 3rd party plugins, please let me know. I don't recall seeing any, but I'll look again.
 

I think Melodyne will do this offline (for audio) but you would need the Editor upgrade for polyphony,
I will look around in my plugs. I think I downloaded some MIDI chord stuff last year

I downloaded a bunch of MIDI chord stuff but found that my guitar to MIDI programs all had chord recognition so I just use that method.
 
check out these links.
 
http://www.hitsquad.com/vocal/about4518.html
http://thepiz.org/plugins/?p=midiChordAnalyzer       this one might be exactly what you want.
http://www.thepiz.org/plugins/? p=midiChords
 
 

I highly recommend Transcribe! by SeventhString. www.seventhstring.com
It has note and chord detection, very quick and easy slow down and transposition sliders and a useful isolation EQ. It's cheap. It's by far the most useful program I have for learning songs and it's written for that purpose.

There is the old fashioned way of "solving" chords and it works very well if you know how to do it. I'm a guitar player but it's pretty similar for piano stuff.
 
Find the root note of the chord. This can usually be determined by whatever the bass is playing (but not always). Just hit single notes on your keyboard (or on guitar just play single notes wherever on the fretboard) until you find one or more likely candidates for your root note.
 
Now you have three main triad qualities to choose from. Major, minor or diminished. Most of the time in a diatonic based composition it will be a Major or minor chord so try those first using the root you just found. If it sounds a little spicier and isn't a main chord in the song (like the first chord of your verse, chorus or whatever) it may be a diminished chord. As a musician you should be able to construct any three of those chord qualities on any of the twelve possible chromatic notes. Pick the one that matches best even if it doesn't match perfectly. There is the remote possibility it may be an augmented chord but those sound rather odd and would stick out more so than the others.
 
From there if the chord is not a perfect match you have two extra factors to figure out. The inversion of the chord and any further qualities like 7th (Major 7th, Dominant 7th, minor 7th, etc) or compound chords.
 
All you really have to do for those is figure out what key you are in then follow the 7 chord 7 mode sequence:
 
I = Ionian (Major scale) = Major chord
II = Dorian = minor chord
III = Phrygian = minor chord
IV = Lydian = Major chord
V = Mixolydian = Major chord
VI = Aeolian (natural minor) = minor chord
VII = Phrygian = diminished chord
 
If you know modal theory basics then all you have to do to figure out more complex chords is play the basic triads you figured out already then try adding notes from their relevant modes. If it sounds like that note is part of the chord it's a keeper. If not leave it out.
 
Then once you feel like you have isolated the specific notes in the chord try rearranging their order to get the correct "inversion". So if you have figured out it is a Major chord but it isn't sounding exactly like the Maj 7th on the recording then try taking your I, III, V and turning it into III, V, I or V, I, III.
 
That's a really half assed rudimentary explanation and it requires you know how keys and modes work (also that doesn't take into account harmonic and melodic minor and their modes but those are both very slight alterations to the Major modes) but that's how I do it and I figure out some REALLY crazy guitar stuff that way. On piano there is far less duplication of notes (you can't play the same pitch note in two locations on the piano unlike guitar) so it should be even easier to figure out.
 
Obviously not what you are looking for but I find just doing things that way MUCH easier than screwing around with software solutions.
 
Cheers.

To be clear, Transcribe doesn't actually write down anything for you. It's a tool that helps YOU analyze by providing slow down, isolation EQ and a basic spectrum analysis based on a keyboard.

And Beep, I'm glad that works for you but that leaves out a HELL of a lot of possibilities such as suspended chords, altered bass notes and deviations from the basic mode (major/minor substitutions etc). It's helpful to know some theory but sometimes you just have to hear what's there. Transcribe helps a lot with that.

Sanderxpander
To be clear, Transcribe doesn't actually write down anything for you. It's a tool that helps YOU analyze by providing slow down, isolation EQ and a basic spectrum analysis based on a keyboard.

And Beep, I'm glad that works for you but that leaves out a HELL of a lot of possibilities such as suspended chords, altered bass notes and deviations from the basic mode (major/minor substitutions etc). It's helpful to know some theory but sometimes you just have to hear what's there. Transcribe helps a lot with that.

Well that was obviously very truncated (I had to stop myself otherwise I would have ended up typing for hours) but taking things on a chord by chord basis (as in operating within a key until the general key/modal method fails then treating each chord as creating it's own key) then working through the various possibilties (as in test out each of the possibilites in the major modes for complex chords then if those fail the oddballs of the harmonic and melodic minors). Really 99% of the time you'll find the answer and if not then some extra screwing around will find the final piece(s) of the puzzle. If it is being particularly stubborn then a quick google search can usually reveal some insights for most stuff. Even if it's inaccurate somebody else' interpretation will point me to the right chord.
 
Then again I have always been a "by ear" guy and I've been doing this stuff for a while. I just think it's a very good skill to have even in this age of super fancy software because I find those types of solutions never really work as well as you expect. Heck... even expensive pro transcriptions seem to screw crap up IME.
 
I guess I'm sounding like a pompass jag off with all that but it really does work. I'm not really explaining it well though because I half arsed it and my brain is off in space today.

I'm a by ear guy too, I think we're having a disconnect here somewhere. Transcribe is just a tool that lets me hear better with its slow down and isolation EQ. The spectrum analysis is a bonus for me that sometimes helps. Most of the time it's off. Still looping a section and playing it twice a little slower is preferable to playing it six times manually at regular speed.

Maybe you should check out Transcribe? You seem to have a completely different image of it than what it is and I think you might actually like it a lot.