Is it necessary to have music theory knowledge to play the ukulele?
No need. An awful lot of players - of just about any instrument - get by or become excellent players with no special theory knowledge.
I believe that the theory side comes later, after you've been able to play for some time. Let's say you spent a year learning theory, then picked up an instrument. You'd be able to play it straight away? Doubtful...
You could read a dozen books on how to swim, but would you then jump in the deep end? Practical first, then find out why.
However - there are a lot of people who just need to know why and how things work. If that's you, then fine. BUT - play the instrument alongside learning the theory, mainly because the practical side will bring the theory to life. You'll be able to hear what the theory is saying.
With all this, I'm certainly not saying don't bother with theory, after all, it explains what happens for the best, it doesn't actually tell you what you must do. But sometimes it's good to find out why something you did that sounded good worked.
Many musicians choose to learn to play their instrument without studying music theory. I compare it to learning to drive a car without studying auto mechanics. you step on the accelerator to go, step on the brake to stop, turn the wheels to change direction. It will take you where you want to go, but you won't understand how it works. That's fine for many people, but some of us are curious about how things work. I'm the kind of person who was reading books on auto mechanics at the age of nine to satisfy my curiosity about how things work. I didn't learn to drive until seven years later. I learned to play the other way, put you finger here and strum and I could play music, but my curiosity drove my to start studying about how music works and just like auto mechanics, I find it very interesting and enlightening.
As others have already said, theory isn't necessary to play an instrument, including uke.
But theory explains the why, and while it's not immediately obvious, theory is incredible useful as you learn to play. For example, theory tells us what chords and notes play well together - knowing this when you're trying to figure out chord voicings or what notes to include as you solo over someone comping will make the experience way better.
Don't let not knowing the theory stop you from getting familiar with the instrument, building those muscles, and being able to get sound out. Just don't neglect it if you want to keep playing.
No. To start with, just learn a few chord shapes and enjoy playing songs that you know. As you get more accomplished with the instrument, you'll naturally want to learn a little more - e.g. where the notes appear on a stave, so you can play melody lines. At that point, you'll start learning music theory from a practical application. How far you take that, is up to you.
When you do learn a little theory, it'll be incredibly useful when you start your next instrument. Knowledge is never wasted.
There are various different areas of music theory. There are bits that represent language and terminology for communicating ideas; there are parts that are concerned with the particular musical choices made when playing music in certain styles; there are bits that attempt to go deep into 'how music works' and why we experience it the way we do. These different areas do overlap of course - I'm just pointing out that there are these different types of knowledge.
Even without trying, you'll almost inevitably learn a little bit of music theory when you learn any instrument - e.g. you'll probably learn at least the names of the chords when you play the ukulele. What more you need to learn depends very much on what you want to do with your instrument - whether you want to play with others, play existing musical scores, write down your own compositions, and so on.
Perhaps a good approach would be to try to learn some basics of music theory so you get an idea of what language and notation already exist to express musical ideas. That way, if you find yourself being limited by your lack of knowledge, then you know roughly where to look to learn more; and if you don't, no problem.
It's never necessary to learn theory to learn how to play an instrument, much in the same way few musicians could (given a calculator) determine the exact pitch of a note they were playing in hertz. You don't need to understand things, for playing an instrument is an independent skill that is not completely related to theory.
To offer up a contrary perspective, I personally learned and taught myself how to play ukulele PURELY FROM THE MUSIC THEORY I KNEW, knowing nothing about actually playing music. (No, Tim, I didn't study theory for a year, then magically learn to play instantly. But I knew what I was doing when I started, I just had to learn technique) Music theory may be an abstraction, true, but it's extremely powerful. The analogy I like to use to describe theory vs playing is that if you learn how to play without any understanding of theory, you have to rediscover all the concepts of music theory by yourself.
People often come onto this site asking why, for example, A7 is used in C major. Theory explains this well, but those who presumably don't know theory well enough get stuck on this idea, having to develop their own way of understanding what theorists call substitute dominants.
Another anecdote: My friend and I are polar opposites when it comes to music. You all already know that I taught myself theory and used it to play ukulele, but my friend is the opposite. He wanted to learn piano off a whim, so he learned how to play a song. One day, I came over to his house and saw him practicing. He wasn't reading the sheet music; he was watching someone who already knew how to play it, and just putting his fingers where they did. One can see the problems with this: Every song you learn is going to be brute memorization, rather than grouping the song into ideas (Chords? Turnarounds? Cadences? Anything?).
The takeaway here is that while music theory isn't a requirement, you're going to want to learn at least some. I'd suggest to anyone taking up the ukulele to understand triads at least, and probably some knowledge of what chords are in which key. If you don't, you'll have a difficult time learning to play songs, because everything you play will be a different thing to learn, whereas with theory, you can shortcut the memorization.
You're never smarter for not knowing something.
Without theory you'll be playing in the dark. You'll play chords and melodies but you won't understand how it all fits together. It will also make it harder for you to change instruments. Music works the same in all instruments. That's what's so nice about theory. And when I say theory I don't mean how to read music necessarily. I just mean the basic understanding of what a major/minor scale is and how it applies to melody, how to pick out chords from a scale and how it applies to harmony, etc. These are really simple concepts that every musician should know. Not only will it help you play existing songs it will also help you to improvise and be creative on your own.
Sure, you could go about it without learning theory. I did that too for the first 10 years of playing guitar/piano, and I can tell you without a doubt that it severely limited me. It's only after I asked questions on this forum and watched a ton of youtube videos that I actually learned how music worked and I can tell you from experience that I wish I knew it from the start. Start with the major scale. Everything is derived from that.
I play the piano, and for that instrument you do have to learn at least some music theory.
I didn't like music theory, I just wanted to play popular songs and impress my friends... But I found it is impossible to play any written song without a little music theory.
Music theory includes notes, the duration of notes and pauses... And then extends to some more complex concepts.
I believe that if you want to play already written songs with the ukulele, than yes, you have to learn a little music theory.
But you can also just play songs by yourself without learning any music theory, watching tutorials instead. Nobody is stopping you and nobody is telling you what you should do, it's your choice.
Still, I would recommend to get your feet wet with some theory It won't hurt you, and I think you'll find music theory is not as bad and boring as it sounds😜
From my experience, I can tell you that no, you do not need to know music theory in order to play the ukulele well.
When I first learned to play the ukulele, I just focused on learning different chords and some basic strumming patterns, and was pretty successful at that. I'd learn new songs, and inevitably I would encounter new chords, which would serve as an opportunity to increase my chord and fingering knowledge.
But as I learned new chords, I eventually discovered that some tabs would show different fingerings for certain chords. For example, the B7 chord was sometimes listed as 2,3,2,2 (that is, push down on the 2nd fret for the G, E, and A strings, but use the third fret for the C string), and sometimes listed as 4,3,2,0 (the 0 means not holding down the A string).
Which one was correct? They can't both be correct, can they? I mean, the fingerings are playing different notes, so how can they both be the B7 chord?
Well, I tried them both out and, while the notes were clearly different pitches, both fingerings sounded just as good in songs that used B7. So what was going on?
(In fact, B7 isn't the only chord that has multiple fingerings. Em has more than one, as does Am7, and so does the familiar C chord!)
That's when I started getting interested in chord theory. I learned what makes a C chord is when there is at least one C note, at least one E note, and at least one G note played (and only those three notes). So the basic C chord fingering (0,0,0,3) is basically two C notes, one G note, and one E note. (By pressing the third fret down on the A string, you're essentially making the A string produce a C note.) It doesn't matter that there are two C notes, or that they are different pitches. All that matters is that, if you have at least one of each C, E, and G are present in some form (and if no other notes are present), then you get a valid C chord!
Then I started learning what makes a minor chord a minor chord, and what makes a 7th chord (like G7) a seventh chord, and why the seventh chord fingerings are often similar to the basic major chords (for example, G7's fingering is very similar to G, A7 is similar to A, D7 is similar to D, C7 is similar to C, etc.).
To tell the truth, I can't tell if what I just explained to you interests you, or if you find it boring. The good news is that what I just said doesn't matter much if you want to play the ukulele well. And should it interest you somewhat, but you're confused about it, you can always revisit it later once you have a stronger grasp of playing the ukulele. Learning music theory should be clearer then.