It is true. For the very few songs I’ve committed to memory, I’m much more able to focus on the actual playing quality. I’ve no doubt it helps. But, for the record:
Questions for some of you experienced folks…
Do you tend to memorize most of your repertoire?
Do you have a particular means of committing a song to memory…ie, is it just from playing it numerous times, or do you memorize purposefully, and if so…how?
(I wonder if it simplifies life in some way to be incapable of reading music)
'Bout the only tunes I’ve been able to memorize over the long term are ones I know, and that have words that I can “sing” in my head as I play. I can memorize other tunes (a few measures at a time) but if I don’t play them regularly I forget them within a few weeks). Songs that I can “sing” I can remember even if I haven’t played them in months – I may initially get a false start but once I find the first note or two the rest of it comes back.
When you can put away the sheet music (if you ever needed it) and play a tune from memory, you will indeed be able to better focus on your playing technique.
The music will also have more of your heart in it, which always makes it sound better… regardless of your technical expertise, or lack thereof.
Oddly enough, I find that closing your eyes also improves your focus on the music… not that that’s a big secret or anything! 
I find that if I get a tune in my head first, it is much easier to make it come out of a whistle… or any other instrument.
Heart and soul are the key factors though… technical matters are of lesser importance.
If you ‘feel’ your music, others will feel it too… and that’s where the real magic lies. 
Yep to both of the above replies. It just seems a way different thing to memorize, for example, “Amazing Grace,” (easy) vs. the seemingly endless assortment of jigs, slip jigs, reels, and what have you that are found in books of traditional Irish music. Must take ages to have all that stuff in one’s head. (I guess that’s what makes AG easy to memorize…it’s already in my head.)
Quote @ emmline
Do you tend to memorize most of your repertoire?
Do you have a particular means of committing a song to memory…ie, is it just from playing it numerous times, or do you memorize purposefully, and if so…how?
I am by no means “experienced folk” but I can say the simp,est thing is -only play what you like-. If you don’t like the tune, it will be much harder to learn it. Record your playing and play along with yourself…that helps memory, too.
Get background info, where it comes from, what it means to you, who wrote it (if known), etc.
Also, I’ve found Amazing Grace can be played about a million ways on whistle, experiment.
If I haven’t memorized it, it’s not in my repertoire. While I will forget tunes that I don’t play much for a while, they are pretty easy to revive or even to figure out again. Every tune I can play, I can also lilt. Most often I can lilt them before I play them, but sometimes it happens at the same time. Almost all my tunes I learn by ear.
In my experience, first you should have listened to a good recording of the tune a lot (A LOT) and you can lilt/sing it (or you almost can). To memorize the tune (this applies to jigs, reels, polkas, and hornpipes, and other stuff, too, probably), break it down into phrases. For each part there are the following phrases: Question, Preliminary answer, Question restated, Final answer. (you can further subdivide). Learn the tune by these phrases, not by measure.
Trick: start form the back, learning the last phrase of the part first, and then working backwards. That way you’ll always end strong as you’re practicing.
Good suggestions, Bloomfield!
Once I’ve learned a tune, I write down the first few notes in a little notebook, since I find if I can remember how to start the tune, I can play it.
Then, once in a while, I play through all the tunes (over a couple of weeks) - because in our session, tunes are definitely “trendy”, and some of the loveliest tunes from previous years fall out of fashion.
pamela
Sviatoslav Richter (a piano concertist) had already retired, when in an interview, he boasted about a “pretty good” répertoire, having memorized about two dozen “tunes”.
Like:
1 and 2: Rachmaninov’s concerti #2 an #3
3: Tschaikovsky’s #1
4: Bach’s well-tempered klavier
etc.
It may be a joke compared to our 16-bars tunes, but the bottom line is Richter too played his best successes from memory…
Btw, remember Glenn Gould’s recordings? Hum, lilt, chant altogether!
I would have to agree with memorizing everything you do. It is ALWAYS better, and I’d venture to say that of any instrument/music you can think of. Of course this may not easily work for everyone as some are practically tone deaf and it’s most easily done with good memory of a recording or skilled player performing the piece. However even if you’re not very good playing by ear or even remembering by ear for that matter, with that handicap you can still use sheet music to memorize.
Once I’ve learned a tune, I write down the first few notes in a little notebook, since I find if I can remember how to start the tune, I can play it.
Then, once in a while, I play through all the tunes (over a couple of weeks) - because in our session, tunes are definitely “trendy”, and some of the loveliest tunes from previous years fall out of fashion.
That is some very solid advice that I think applies to any form of music, spare maybe the latter point when playing hymns (where they are all old). But definitely it is always just getting the first few notes that’s tricky, once you get them you’ll remember the whole tune if you did have it memorized.
As a new player - I’ve wondered the ‘best’ technique. Should I memorise or not - what I do find wierd though is if I ‘close the book’ I’m lost my way very quickly - but if I read the music and play my fingers seem to do the business automatically - without concious effort - a bit like driving I suppose - after a while it just happens you use the visual clues without thinking about it.
I agree with Zubs and Bloomie above. If I can’t hum the melody I can’t learn it, let alone memorize it. And although I learn almost all of the tunes I know from the dots I close the book and play from memory as soon as I can. But I cannot emphasize too much the importance of learning to hum the tune.
Mike
Plus snork, grunt, burp, and fart. He sure wasn’t shy.
jb
Oscar Peterson too (another Canadian)
I must add that, contrary to what Zub said, it doesn’t automatically follow that you are then able to play the tune. You’ll have to properly learn your instrument first. And honestly when you’re on a level where you discuss memorising Amazing Grace, you’ll still have a bit of a way to go in that regard.
My own son, ten years old, has a remarkable ear for tunes, whenever I sit in a corner somewhere playing my pipes and himself sitting on the floor playing with his cars or whatever I can hear him hum along, even the contrary tunes I don’t play often, he has them spot on. But is he able to play them on the concertina. Well, no. But I am sure that if he keeps practicing his playing skills he eventually will.
I think here this thread touches on subjects also touched upon in the ever returning sheet music discussion, I don’t think it’s really about sitting down ‘memorising’ tunes, it’s about letting them seep into your brain until they are ready and once you’re there you’ll find you can sit down, play them and move around in them freely. I think that’s really what’s meant by learning by ear.
As many of you know, I see no problem with sheet music to learn the tune, then at some point, you put it away and put your own touches on it and get it into your fingers, body and mind.
Emmline, some other fun songs to practice on are kids’ songs such as Twinkle Twinkle, Jesus Loves Me, etc., if you have little one in the house, they’ll enjoy hearing songs they’re just learning. Then you can put some rolls, slides, or cuts, or try some other ornaments in them. I KNOW I’m not the only parent who has Irish-ized (badly I’m sure) some children’s music! But they’re easy and they’re already in your head, so they’d be good do hone your ear-learning skills even if they don’t make it further than your living room!
I do most of my learning from sheet music, after playing a tune or set a few times through, I take to glancing away or closing my eyes with the music still in front of me, then playing half the part (Bloo’s first ‘question/answer’) and relying on memory for the second.
During the day I tend to play things through in my head. As long as I have a mental feel for the tune I’ll continue. If I forget how it goes I don’t pursue this, or I’ll start remembering incorrectly!
My biggest challenges are the multi-mega-part jigs, like the Kilfenora, Frieze Britches, Old Grey Goose…There I concentrate on what is repeated in the various sections, and plotting a journey from section to section. Okay, first part starts low, second high, third low, fourth high, fifth higher, all of them have these two phrases (better be sure my fingers know that phrase down pat).
Another, far less fun way to memorize is to write it out, phrase by phrase, pausing at the end of each phrase to play what you just wrote and what you’re about to write.
More and more I find that I’m learning patterns that are repeated and repeated all over the place in IrTrad. I have mental names for all of them that probably make no sense to anyone but me, ‘scale up’, ‘scale down’, ‘twiddle down’ and ‘twiddle up’, ‘three bounce’, ‘drop’…I don’t know how it helps, but I know it does. I’m not memorizing the notes, I’m following a path of patterns.
Lastly, if you can find people to play with, it becomes a lot easier to remember what follows what.
Funny that you would have picked Sviatoslav Richter… after an embarrassing memory laps (I think in 1980), he almost always played off a score in concert. (Which, I’ll admit, doesn’t mean he didn’t know the stuff by heart.)
Peter mentioned the stuff seeping into your brain: For me that doesn’t happen necessarily effortlessly. The tunes that I learn because I like them I will often have listened to a hundred times if not hundreds of times (at work, in the car, while reading). Then finally sitting down, playing along with the recording and figuring out where the fingers go is a matter of half an hour. But I’ll play the tune then for days or weeks, before it sits and I can play it at session or for others. During that phase of “setting” the tune in my mind, the most important part for me is not to compromise the rhythm. That means, if I find myself wanting to speed up this easy passage here, but slowing down that hard one there, I am going too fast. Disciplining myself to get the tune in the groove, slow and steady, is the real work involved in learning a tune, probably because I am not very far along. (It is getting easier and easier.) But if I don’t have the rhythm right, I can’t speed the tune up much, and I can’t play with it (put a roll in or leave it out, breathe in different places not always the same one, and so forth).
Oh, Zoobie: I can lilt many many more tunes than I can play. I’ll play them all one day. 
Depends on the tune. Some just “stick” if I play them a few times, others I have to memorize in bits. Go figure.
forgot to mention one thing: Tunes that I hear live stick in the brain much MUCH more readily. They’ll play a tune at session a couple of times, I can lilt it. If I’ve recorded it, I can then learn it off that in a day or so.
The best thing, btw, is to get to know some good players, and then invite them all to your house for a session. Give them food and drink (no musician resist the temptation of it), chat a bit, and after no time the insturments will come out and you’ll have some great tunes that will go on buzzing around your mind for days. (Tape it, if you can.)