Part I
Point is to design and build personal audio system to match your needs. Also my goal is to be flexible which means you will be able to take any of the components and use it elsewhere.
Evry sound system can be devided to several common blocks - 1) source of signal; 2) amplifier/equilizer; 3) speakers. I gonna start from the "tail to the head" which means - 3) speakers.
Because the whole system need to be flexible i decided to look at some parts target at car audio. In this way of thought i choosed a car type subwoofer speaker. Its not important does its a car speaker or just a standart one that you can find on the net aslong as the sensitivity and diameter of the speaker are high. Small drives, especially for low frequencies is just no good. Bigger is better. There is something else which you wont find on a standart speaker and this is the Dual Voice Coil. Evry speaker use one voice coil with fixed resistance (usually 4 or 8 ohm). Dual Voice Coil (DVC) speakers have two coils usually 2 or 4 ohm resistance each and four wires instead of two. Both coils need to be connected before speaker to be used. The advantage of DVC comes allowing you to connect both coils in different configuration to take the maximum of your amplifier. Lets take for example Pioneer TS-W256DVC. This drive match our requirements - 87dB sensitivity, 25cm diameter, 350W RMS, DVC with two 4 ohm coils and perfect frequency response for a subwoofer all this at good cost - 60 euros. Now depend on how you connect the coils (usually you get this into the user manual) you can 1x 8 ohm, 2x 4 ohm or 1x 2 ohm.
to be continue ...
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