I've called this post, although adding to another thread, Tuning in a box , Illusions and Delusions.
I was reading about some new members ( it's a common thing so it's useless to mention whom) and their tuning problems and then I remembered the reasoned guide to tuning that Pete Thomas has published on his site
http://tamingthesaxophone.com/saxophone-intonation-tuning
It is amazing how much time a lot of people spend on " cold tuning" at home and how very little they learn to play in tune with other instruments ( which is really what counts).
So I decided to revamp this issue and to quote Pete saying:
Tuners are fine for tuning your tuning note to, or for reference: ie as a way to see if certain notes are more out of tune than others. But they should never replace your ears. Playing scales or long notes and constantly watching a tuner may be counter productive, but glancing at it occasionally after starting a note can be very worthwhile to check if you are in tune or not. It's important not to get hung up on perfection.
That is if you don't want to be like someone " tuning" his engine in a garage and never ever taking the car out and see what it does on the track and more importantly how one drives it when on the track with other cars!
I find it funny that tuning is such a great hung up for a saxophone player and that the emphasis to tuning " problems" is always put on the gear.
So your horn, your neck, your mouthpiece, your tuner, to which you spend time tuning, all are no good
..........
Of course, all of these things are helping you to tune but given you are not doing anything completely wrong and within reasonable limits the player is the most important tuning device.
It is the player who plays ( and more often than not doesn't) plays in tune.
Playing in tune is obviously also a problem for other wind instruments but brass players see it a lot more as an issue with themselves than it is an issue with the equipment.
The thing is that they MAKE the instrument play in tune because they are the playing implement a lot more than the instrument is.
Just a thought for those who want to buy tuning in a box.
It comes from a Brass musician blog
http://brassmusician.com/tips-for-playing-in-tune/
"Last, and most importantly, any musician must learn to hear the notes they are playing to assess their tuning. Do not take a single word of advice on this page if you cannot hear that it actually makes a beneficial change in your sound. Every instrument and every player is different, the only thing that must be consistent is your hearing. ......."