If i have a piece written in the bass clef and I need to transpose it for baritone saxophone in EFlat how can I do it? The first note is an F, would this become an A when trasposed? Does the clef change?
I play bari sax too, and there is a nice trick you can use to sightread bass parts without mucking about transposing.
Ignore the clef, add three sharps to the key signature, and otherwise play it as written. That first space note is an A in bass clef, but we're ignoring the clef (in other words, replacing it with treble) so we play an F instead, adding accidentals according to the new key signature.
Accidentals are where this gets interesting, especially "advisory" accidentals, which are supposed to be written in brackets but often aren't. For example if a piece is in Eb and you have a bar with an E natural in it, an Eb in a later bar might be written as Eb instead of E(b). Otherwise flats and sharps work normally, except if you're already on a flat or sharp note, in which case you double it - if the original piece is in C then we're in three sharps (A), so an A on the bass part is an F# for us, so an A# on the bass part would become F##. The natural sign then means sharp or flat depending on (a) if it's "advisory" and (b) if the key signature is flats or sharps respectively.
Baritone sax (and all the saxes) read treble clef (in most circumstances there are exceptions). So you want the 'Eb transposition' PLUS an octave up.
'In Eb' means that when the player sees C, the note that comes out is Eb. So if you want to hear F, write D.
This printout clearly demonstrates the dodge that Baritone Sax (and Brass Band Eb tuba) players can use to directly read bass clef concert pitch. Switch clef, add three sharps!