A synthesizer usually has voices which are composed of 4 to 8 single elements. A brass voice for example can be put together flexibly by combining 2 solo trumpet samples, trombone, section etc. Then, 16 of such voices with 4-8 elements each can be combined to a 16-part performance (or combination, different terminologies). In total adding up to 64-128 elements per performance at least theoretically.
You will never find this architecture in an arranger.