Fine trumpet , alto sax recordings?

Mark Isham is as relaxed and mellow a trumpeter as I can imagine, but he is real jazz not smooth jazz, IMHO! He is not challenging jazz either, so anyone who thinks jazz has to run the "unsophisticated listener" out of the room to be good stay away!

I only have 2 of his albums though, Blue Sun and Afterglow. Afterglow is a soundtrack. He does a lot of soundtracks. He also played with Van Morrison during his spiritual, ethereal period.

I'd start with Blue Sun and if you like that explore further.

Two somewhat lesser known recordings that come to mind.

Frank Morgan - Listen to the Dawn - beautifully recorded on Verve in early 90's - much of it duets with Kenny Burrell.

Helen Merrill - Brownie: A Tribute to Clifford Brown - also recorded in 90's on Verve. Helen Merrill singing with a stunning trumpet choir consisting of Roy Hargrove, Lew Soloff, Wallance Roney and Tom Harrel - a unique and beautiful sound and stupendous recording.

This cna be pretty confusion to choose from   trumpet and alto sax.

This is basically the trumpet key. Generally speaking, trumpet comes in two types that is two category of keys one is Bb and second is C.

The Bb is a standard key that you will find in almost all the trumpet sold in the market. The Bb key is the modern trumpet key which gives a range of versatility in tone, music, volume, and sound. Overall, you can explore all the genres of music with this key.

A student trumpet is always a Bb trumpet as it is used for everyday practice for honing the skill and for playing different genres. We also recommend you to buy a Bb student trumpet.

On the other hand, a C trumpet is the less common form. This one you will find in professional bands. A C trumpet is a costly affair so on the student level, it is advised to stay away from it. Nevertheless, when you advance in your skills you can buy a set of this one too.

https://disappearsmusic.com/best-student-trumpet-for-beginner/

I just bought a cd by Kenny Dorham called Quiet Kenny. Very nice mellow trumpet similar to Chet Baker.

For smooth, agree with David Sanborn, would also check out early Spyro Gyra... a good place to start are the albums “Catching the Sun” or “Carnaval”. Would also try “Wizard Island” by the Jeff Lorber Fusion, or “Breezin” by George Benson.

in the straight ahead vein, I would suggest “Covered” by the Robert Glasper Trio, anything by Billy Taylor, “Time Out” by the Dave Brubeck quartet, “Ballads” by John Coltrane, or “The Incredible Jazz Guitar of Wes Montgomery.

not all of these are strictly trumpet or saxophone records, but all are melodic, relaxed, and accessible.