Most professional musicians can't begin to afford most of what y'all call audiophile grade gear. Certainly there is very good sounding, low-cost gear on the used market if you know what to look for, but pro musicians are not gear heads.
Cost aside, pro musicians generally don't make a lot of money. My wife is a life-long pro classical violinist who played 20 years with the San Francisco Ballet Orchestra, as well as many other orchestras here in the San Francisco area. She still subs with the Ballet and did a show last week with the Oakland Symphony. She has NO interest in audio gear and if it weren't for me, would likely have little more than a boom box. She's not alone.
I've helped a number of her colleagues put together good sounding, low-cost systems of decent used gear and they are thankful for the help. But on their own, they are often pretty lost.
Think about the level of technology a violinist uses. The instrument is tuned by turning a wooden peg! There are no electronic pickups or other devices. Violins don't even have frets!!! A violin bow is a wooden stick with HORSEHAIR! They really are a 19th century technology. And you think they can understand anything electronic?!
