Those prices are actually pretty competitive.
Personally, anything big like that I ship through an independent. Here in Tulsa I use Box Brokers. They have contracts with multiple LTL shippers.
This results in lower prices but more importantly, the ability for third party insurance that is really insurance, not the declared value nonsense of UPS and FexEx. What you do is box everything up then strap it to a pallet to get pallet rates. If you can't build the pallet yourself the shipper can do it.
It's still going to cost a fair chunk of change. When I sent a palatalized shipment of three X-CS Encores, two speaker stands with dual 8" subwoofers and HX300 amps built in, a Marantz SR series AVR, and a box with cabling from Tulsa, OK to Portland, OR it cost me a little over $500 (including building the pallet).
Shipping large and/or heavy objects, especially with good insurance, isn't cheap.