Different people like different saxophones. It depends what style and who you are. Tenor produces a jazzier sound, but you often sacrifice having the melody for a counter-melody, or sometimes even just tones in the background. Alto is generally a good choice for concert band. for marching band, the baritone or Contra-bass Saxophone is a good choice, to enhance the band's sound.
As for brands...
For alto: stay away from yamaha. Julius Keilwerth st 90 series 4 is a good model, and my personal choice.
Tenor and Baritone : Selmer.
I do not play contra-bass, and therefore, cannot give you a good brand.
Low B flat for most, but some saxophone models have a low A key below the octave key.
An alto saxophone is in the key of E-Flat, or Eb
These are the most common types of saxophone. Alto and Barritone saxophones are Eb transposing instruments. Soprano and Tenor saxophones are Bb transposing instruments.
The Alto Saxophone is in the key of E flat. That means that an E flat on the Alto Saxophone is the same pitch as a C on a piano or other concert pitch instrument.
The saxophone has been modified over the years but not hugely. the f# key has been added to the saxophone for it to be played a semitone higher
Low B flat for most, but some saxophone models have a low A key below the octave key.
An alto saxophone is in the key of E-Flat, or Eb
use every key on the saxophone
The Soprillo piccolo saxophone is a transposing instrument in the key of Bb. Same as the tenor sax.
These are the most common types of saxophone. Alto and Barritone saxophones are Eb transposing instruments. Soprano and Tenor saxophones are Bb transposing instruments.
The Alto Saxophone is in the key of E flat. That means that an E flat on the Alto Saxophone is the same pitch as a C on a piano or other concert pitch instrument.
Some E-flat instruments include the alto clarinet, sopranino saxophone, alto saxophone, baritone saxophone, contralto clarinet, and the tenor horn. There is even an E-flat tuba, but it's not regularly used.
The saxophone has been modified over the years but not hugely. the f# key has been added to the saxophone for it to be played a semitone higher
E flat
It is the A# with the low key the low key is the key that is below your left thumb in rest or The low key is the key that is below the octave key and the left thumb rest position.
a saxophone (learn to spell) has no flat keys. There are different keys for each note. There is no individual key for a flat
Alto Saxophone is a concert Eb instrument.