JTR700 Standard Series Student Bb Trumpet JTR700 Lacquer. The Jupiter JTR700 is a better quality student trumpet with clean lines, excellent build quality and superb intonation. It is free blowing with a focused, centered tone, and is a fine instrument to start on and to pursue secondary studies with. It is available in a lacquered brass finish or a silver plate (select from dropdown menu). Notable features include stainless steel pistons, 1st valve slide thumb saddle, and an adjustable 3rd valve slide. It has a .460 in. bore, a 4.8 in. bell and comes with a wood-frame case.