Originally Posted by ANtubenut
1. Most head units use a blue wire to trigger a power antennae or external amp. This wire activates (goes hot) shortly after the main battery power is turned on. In other words, the amp turns on after the BATTERY + wire is hot. The delay gives the amp a chance to "charge up" (for lack of a better term).
2. Ground wire: Your ground wire should go from the Bazooka all the way to the battery. It is ok to also ground it to the body of the car along the way, but always run a ground wire from amp to battery.
3. >the red wire is hooked to 12v constant (yellow on my head unit)..
Your Bazooka should be hooked to the battery + (with a fuse). The power wire for the head unit might be too skinny to handle the Bazooka amp. This does not contribute to the turn-on thump, but the smaller wire can limit the available electricity for the amp.
True, to a degree. The remote +12v source of the headunit, dedicated to an external component is not always the same as the antenna power. When the source unit goes from tuner to another form of media, the antenna lead will often turn off, as the power antenna is now off. However, the voltage of a remote turn on lead, is quite small, and is measured in milliamps, and is on as soon as the key is turned, no delay. Today's amplifiers take care of turn on thump, sometimes called a soft turn-on.
The ground wire should always be as short as possible. While it is true that in some installs, especially vehicles that used galvanized steel or have fiberglass panels, grounding to the battery was a must, that is hardly ever the case anymore.
When installing a BTA50FH or BTA100FH, you can always connect to the constant power of the headunit. Not only is this a fused power source, but it is also a more than adequate power supply for the BTA50 and BTA100 Tubes.