Piano and Trumpet can sound bright

If you're up for a speaker change, you could certainly change that quality in the sound. However, you'll change pretty much everything else too. I'd try replacing the silver streaks with something that's all copper - there are tons of options.

I think Learsfool makes an excellent point!

I hear live trumpets often at the local jazz venues. Yes at times they can be bright but never are they irritating or harsh.they don`t lose their inate beauty of tone.

Charles1dad, it depends on who's playing and/or where your sitting.

Stage musicians as a matter of fact usually won't use instruments that can be irritating or harsh. Obviously with Miles Davis it's not the case.

The speakers mentioned
1. are not tube friendly in general
2. very sensitive to the amplifier choice (I'd probably use them with such amps as Creek 5350, Unison Unico, Arcam, Nad C372 and other shy and polite amps).

Since quicksilver silver90 is nowdays 'endangered', I'd recommend to keep this treasure and replace speakers. Have Totem Forests floorstanders for very cheap(shame to post on A'Gon for that price). Will match Silver 90 like butter'n'jelly. I guarantee that for this recommended upgrade you'll get money instead of spending from selling yours and getting mine.