QUOTE(Violinia @ Dec 29 2005, 07:25 PM)

Well?
Violinia
I'll try to answer as best I can

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I think you're working on the assumption that people with perfect pitch only have perfect pitch at A=440, and anything else renders it useless. To within a few hertz, I can ignore a tuning difference. I'm certainly aware of the difference, but can 'accept' it; there's the odd moment where, if I think too hard, a note could be one of two nearest matches, but if I relax and trust my first judgement it's fine.
If A is further from 440, such that 440 or thereabouts is a different note entirely, then I find it harder to use absolute pitch. Reading discussion from others with perfect pitch, particularly those who work with early music at A=426 or A=404, it is possible to learn several sets of perfect pitch and switch between them as needed. My first piano was a semitone flat, and I had that for a few years but now have perfect pitch at A=440 so I might, myself, have made the switch.
In circumstances where A isn't 440, though, I switch to relative pitch. As I see it, I don't lose anything by having absolute pitch: I can use it when it's appropriate to do so, and use relative pitch otherwise.
Now I'll digress (or ramble

) slightly: Violinia, most of your musical work - as far as I know, and as your forum name suggests - is to do with the violin. Despite my relatively poor violin playing, I see the violin as being a 'relative pitch' instrument - to play it, one needs to pitch intervals between one's fingers to generate successive notes. Position shifting is shifting the frame of reference, much like changing between A=440 to A=500 or whatever. The ability to read successive pairwise intervals between notes on the page and accurately map this to successive intervals between one's fingers on the appropriate strings is important to develop good intonation.
The piano, I'd see as an absolute pitch instrument - you want to play the C# above A=440? Press the right key. One doesn't need to read the interval and pitch the next note accordingly - merely read what the note is, and press the right button so to speak. One can get very far playing the piano merely by pressing the right notes at the right time - there's a famous quote by Bach along those lines. Playing the violin, on the other hand, one's intonation will be terminally shoddy if one cannot pitch intervals reliably.
When playing the piano or harpsichord, particularly when playing unfamiliar pieces, I look at the music and let my hands do their own thing. If there's a leap I miss, or my coordination otherwise lapses, I usually notice the resulting wrong note by expecting a certain sound to be made and there being a discrepancy. Furthermore, by knowing what the note on the page is and what I played (using my absolute pitch), I can move my hand to the right place on the keyboard and continue without significant interruption.
Anyhow, here's my question for you, if you're willing to indulge me: would relative pitch work as effectively in that situation?

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