Big band is tricky - and the conventions are quite difficult to pick up, unless you listen to a lot of it.
Guitar and piano are too loud and too bright and in your face. Try to imagine what the audience would hear if they were there. The piano parts are always a bit percussive to make them audible, but from the audience the treble gets lost, because the piano, like drums and guitar are probably the furthest away, and HF drops off with distance. The guitars even when amplified don't usually have clarity and HF - and the amps are rarely turned up loud - so your guitar is very up front and detailed. Live, like the piano - they don't usually cut through at all. The brass and woods by convention are opposite sides of the stage - so when they do-wop, as big band arrangements often do - the trombones and trumpets are clearly in a different place to the saxes and clarinets. I struggled to hear these sections as two distinct parts of the band - and trumpets appeared to be in the middle when the piano and guitar gave them space. Remember big band has the saxes, clarinets, trombones and trumpets as primary instruments with the bass, and the piano and guitars are essentially rhythm background -apart from when they have feature songs. The bass appears to be electric, but very low in the mix and EQ'd to be very bright too?
Some other big bands put the brass behind the woods section - but usually these too sound like two separate sections.
Here's a couple of clips that I think work quite well. Same orchestra - but a modern version and the original. the guitar is hardly there unless for some reason it needs to be. The old one has a famous drummer in it - sadly passed away long ago but I did quite a few shows with him. He was the inspiration for the Muppet Show drummer - Animal. The guys name was ronnie Verrell - a brilliant drummer. In these clips note how the piano can be heard when it needs to be, but usually, it's almost missing.
The last clip is less good. The singer was very well known here, but when this was recorded, at a USAF air base in my area - I was quite young. My role as a sound assistant was mainly running cables and setting mics up - not allowed anywhere near the mixer. I was also convinced she was drunk. She spoke to me backstage when I was setting the mics out and her speech was very odd. The mix was not so good on this one, and some of the players were not remotely as good as the Syd Lawrence orchestra. I got my first taste of big band with them - in a dingy recording studio near Liverpool - all cigarette smoke and smelly. The same studio the 10cc song I'm not in love was recorded in!
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