Home Pro Audio Asylum

Pro studio recording equipment and music production/industry.

re:many varables

Basically, a zoble circuit will control the impedance rise at resonant frq. that occurs in the circuit (woofer, cabinet, room air, crossover, and amplifier..plus speaker leads.

All these are contributors. I know of no company that has a totally flat impedance curve unless they have found a way to eleiminate wire in general..be it speaker wire, crossover wire, or voice coil wire. Even esls have wire..so absolutly, phase shift free and flat impedance curve, power curve through the entire range is impossible. even if it could be done in therory, just moving your body to another location in the room would change the air loading behavor , thus causing some interaction with the motor system that would change the character just enough to rule out "perfection". The zobel circuit, carefully used with controlled internal enclosure dampning, and predictable frontal cone loading with the crossover as close to the amplifier as feasable does yield promising results. I would say the obvious "least trade offs" would be to map the drivers inductance curve (if using moving coil units) and use said driver only within the range that the inductance is most stable with the zoble circuit applied. Formulae for zobels usually does not account for changing inductance, changing power band and changing frequency. Sometimes just the "right" enclosure loading without a zobel will yield a flatter impeadance curve than with a "formulated" zoble. What it all comes down to is integrating the speaker system into a vast number of room varables and getting as predictable musicality as possible. This is where the magic lies. VNF listening (very near field) does 3 things that are of advantage. 1. you are masking room acoustics. 2 You are listining to the speaker at or about where it's frequency response was documented. 3. you can have low power and modulation..which equals lower distortion. Obviously, this is uncomfortable at best to be right in the pattern of most speakers..but if loudspeaker manufactures would design their products with the 3 meter rule in effect...we all would enjoy higher fidelity..or even 4 meter to 5 meter. When I design and build a loudspeaker system, the crossover is usually designed in my lap or seating position and tweaked until the focal lenght is appropriate for that distance.

Their is much work left on high fidelity loudspeaker design for the future. We are just scratching the surface after 77 years of usage.

Volumes could be written on the inabilities of loudspeakers to behave as needed in all circumstances.


This post is made possible by the generous support of people like you and our sponsors:
  Kimber Kable  


Follow Ups Full Thread
Follow Ups
  • re:many varables - RBP 16:54:41 04/22/02 (0)


You can not post to an archived thread.