When i play notes on alto saxophone i hear like static in the notes. when i play loud u cant hear it but when its mf mp or p you can hear it and im doing jazz band with saxophone (im a new player)My brother said to loosen neckstrap (he played bari and alto sax, but now playyrs baritone and trombone) but that didnt work. Can anyone help me? i think it might be my embouchure

Static is a bit vauge, but I will give it a try.

Either you have spit build-up in the mouthpiece and saxophone, or your have too open or too hard a reed.

If it is spit you are talking about: Swab your sax after each time you play, and even do in the middle of a session. Get some pipe cleaners and clean out your upper and lower octave holes. When you are playing it is quite normal to suck in the spit from the mouthpiece, sounds nasty but its your spit anyway.

If it is air you are talking about: Check your mouthpiece, what is the facing/opening? As a new player you should be using .075 to .085 on alto. If your mouthpiece is something like a selmer C* that should be ok. Check your reed, what is the strength of your reed, you may need to go softer.

That being said it is ok to have an airy sound playing jazz, and it is actually a prefered.

Hope this helps
CJ

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Either you have spit build-up in the mouthpiece and saxophone, or your have too open a mouthpiece or too hard a reed

I tmight just be a lot of spit in the mouth piece or neck. Try sucking into the mouth piece next time you practice to try to get the spit out. I know it sounds gross, btu give it a shot.