TT/Tonearm/cartridge interaction theory?

Here are my favorites:

http://www.audioasylum.com/audio/vinyl/messages/1240.html

http://www.deadwaxcafe.com/vzone/cartalign.asp#vta

http://www.walkeraudio.com/fine_tuning_your_turntable.htm

http://www.tnt-audio.com/sorgenti/vta_e.html

http://www.theanalogdept.com/tonearm_alignment.htm

It's really quite simple. You have a stick. At one end is a rock and at the other end is a magnet. The stick is physically held in place such that movement at the rock end is mirrored at the magnet end (think of a see-saw). Additionally, the magnet end of the stick is surrounded by thin wire metal coils. As the rock end of the stick is dragged through the undulations of the record disc it moves in both the horizontal and vertical planes. At the magnet end of the stick this movement generates a small electric current through the surrounding coils which is then carried via an interconnect cable to a phono preamp.

Based on this description, the purpose of tracking force is to keep the rock (stylus tip) in contact with the record groove walls and to keep the magnet centered within the surrounding coils. Cartridge manufacturers usually give a range for tracking force. It's a little like tire pressure in cars. Depending upon what type of ride you like, the roads you drive on and your driving style the "correct" tire pressure could be a the low or high end of the recommended range. Tracking force is ultimately set by ear.

See these links for detailed explanations of all the other factors (SRA, VTA, azimuth, tracking error, etc.) that effect cartridge setup and sound quality:

Walker Audio

Laura Dearborn/van den Hul

Good Sounds

Audiophilia

Audio & Music Bulletin

A particularly important aspect is matching the compliance of the cartridge with the effective mass of the tonearm. The compliance being the springiness of the cantilever on the cartridge.

Since we have a weight (tonearm+cartridge) riding on a spring with minimal damping (unless the tonearm bearings are shot) you have a resonant system, and the resonant frequency is affected by the mass and the springiness (compliance). It is good to keep the resonant frequency below that of the lowest frequency in the music (15Hz), but not too low where warps in the LP could excite it. 8-12 Hz is ideal.

It's all here....

http://www.theanalogdept.com/cartridge___arm_matching.htm

There's also an accurate easy to use (no formulas) compliance chart at:

www.cartridgedb.com

Does anyone know the physical difference (i.e. how they're measured) between dynamic compliance and static compliance, and whether you can use them interchangeably in calculating resonance values. For some reason, cartridge manufacturers only seem to spec one or the other.