Loudspeaker Design Overview Page 2
The Elvis School of Medicine
One day Elvis Presley went to his doctor with a headache. His doctor gave him codeine which got rid of the headache. That night Elvis called his doctor and said “I have to go on stage but I am so groggy.” His doctor gave him an upper. After the show Elvis called his doctor and said “I can’t go to sleep.” His doctor gave him a sleeping pill. In the morning they had trouble waking Elvis up so he took the pill that helped him not be groggy. After three months Elvis was taking 40 pills a day. If the doctor had given Elvis an aspirin, a pill that was less effective at getting rid of headaches, but had virtually no side effects, Elvis may still be alive today (except for those fried banana sandwiches).

What the heck does this have to do with design, you ask? In the case of Elvis, and design, if the side effects are not controllable then it does not matter how effective a design process is. An “inferior” circuit that has weaknesses that can be addressed will perform better than a “perfect circuit” that has a fatal flaw. If it takes 32 components to cross over a tweeter, then a light should go off that something is terribly wrong. Complex error correction circuits, by their very definition mean that there are a lot of errors, or one really big one! When I am presented with this scenario, the temptation is to keep on going because the original premise was so cool but eventually it must be realized that until a scenario and design can be formulated that conducts this new idea in a mature and simplistic manner, it will not be successful. It does not mean that you have to abandon it, but you must never make your customers pay for your research and development.

Solder joints, while convenient and necessary, sound bad. I have constructed circuits that are identical but for the number of solder joints and the fewer solder joints, the better it sounds. Therefore, I believe that solder joints cause sonic degradation and know that each solder joint adds greater chances of breakage, failure and inferior design. A circuit with two hundred and two solder joints has two hundred more posibilities of failure than a circuit with two joints.

The Function of a Loudspeaker Enclosure

The function of an enclosure in a dynamic driver system is to absorb the rear wave of the driver while not causing any sonic degradation to the front wave. It can also serve to bolster the low end response of the system by adding resonance. Well controlled resonance. The enclosure must function like the heat sink on an amplifier, which draws heat away from the transistors and dissipates it. In our enclosure, it is the rear wave energy that must be drawn away from our driver so it may be dissipated. Heat cannot be drawn away from the transistors if the material used is inert to temperature. We use aluminum because it absorbs the heat and dissipates it effectively. If we used cotton balls as heat sinks, which are incapable of absorbing and dissipating heat and our transistors would burn up. We would have a poorly designed heat sink because it would be incapable of serving its function.
| Last | 1 | 2 | 3 | Next |