QUOTE(Cath @ Jan 9 2009, 12:37 PM)

Violinia, Kemn, do you think then it is okay to use an electronic tuner when playing with a piano so that you are tuned with equal temperament? What about when playing with an orchestra? Are other families of instruments natural tempered in the same way as string instruments? I would assume it would be the case with brass but what about woodwind?
There's not one answer to this, and what is best for a particular person depends upon their own ear for tuning; also their ability to avoid open strings. |In some circumstances, even a very good piano tuner might use an electronic tuner, e.g. if the piano was to be used with a rock group whose bass player tuned with one; in that case you might as well do the same. Pianos to be used in "art" music will not be tuned to an electronic tuner. As I explained above, on a well tuned piano, the tuner will eliminate beats when tuning the octaves; their frequency ratio will be slightly larger than 2; and the electronic tuner will show the bottom register as flat and the top as sharp. Also, although the notes within these octaves will be close to equal tempered, they may not be exactly so, inter alia because of the adjustments that the tuner's ear will suggest to make crossing the mechanical break points (chaged numbers of strings per note, string windings) sound as uniform as possible.
If you don't trust your ear, I suggest that for each string you adjust your tuner until it thinks the corresponding piano note is in tune (in the middle register the adjustment may be small), and then tune your string to that. However, this is a complicated subject; at the highest level some string players find piano tuning very unsatisfactory and try to stay with their string quartet or trio.
Most modern wind instruments are nominally equal tempered, but good players know how to tune them dynamically for the musical circumstance and good orchestras play in equal temperament only when fixed pitch instruments (piano, harp, tuned percussion etc.) are an important component of the work. It is standard practice for a second horn to play just intervals with the first, and the horn has three possibilities to achieve this: the lip, the hand in the bell and (except for the very lowest register) alternative fingerings. A professional quality trumpet will have levers to adjust the length of the tubing that is added by depressing the first and third valves. Slide trombones have similar freedom to that of the strings. Tubas are perhaps the most dependant for tuning upon their players lip, though they have some alternative fingerings also. I know less about modern woodwind, though most have alternative fingerings from their second octave upwards and closing holes well below the lowest open one is a standard way of flattening the note slightly. My understanding is that on most of the woodwind, the player learns how to make tuning adjustments with the embouchure.
In the 18th C, at least one flute method gave fingerings for 17 notes per octave: seven naturals and five each of flats and sharps; I don't know whether this was possible throughout the lowest octave. Of course, in those days nothing was tuned in 12-note equal temperament.