What is a French horn rip?
With the French horn, and many other instruments, it is common to start a measure with a "rip," meaning that you glissando from nothing to your pitch, but arrive on your pitch on the beat the note is written on.
How does French horn change notes?
The French horn consists of about 20 feet of narrow tubing wound into a circle. The player obtains different notes on the horn with a clear mellow sound by pressing the rotary valves. When the player pushes down on a rotary valve it pulls a string that opens or closes different valves.