As one option, connecting three speakers in series (balancing the coils) you will wind up with two 18-ohm branches which you can parallel to achieve a net 9-ohm load. Then if you connect the next three speakers in the same way, and parallel with the first complete set, your final net load will be 4.5 ohms--definitely close enough to 4 ohms and probably a bit easier on the Precision Power amplifier.
The fact that your local store told you that this could be done leads me to believe that they have a good grasp of circuit arrangements to get to the optimum load. In addition, I would be sure that they know there is an extra half-ohm of buffer since the amplifier is rated at a minimum 4 ohms when bridged at 600 watts. I would not want to tread anywhere below that point after looking at the circuit board layout. Your dealer sounds like he is guiding you toward a high-performance system with high-reliability built in.
Q: I was listening to a CD and the sound just stopped. I thought it was at the end of a track and turned the radio off. When I turned it back on later, it seems like the CD is playing but there is no sound. There is no sound from the radio or the CD, though all the power seems to be on and all the lights work. I checked the amplifier fuse and it was good. I didn't see any fuse labeled for the speakers.
I have an '06 Chevy HHR and the warranty ran out last month. I always turn off the power to the radio before I turn off the car, because occasionally when you start the car if the radio is on there is a very loud sound--too hard to describe. Besides startling me, I am always afraid it will damage the speakers. I would appreciate any help you can give me.
Karen Alfrey
A: Without knowing details on the product or how the system is connected, I can't get specific, but I can lead you through some tests that will get you to the answer.
If the sound suddenly quit with no unusual noises, there are a couple of first steps. Since the amplifier fuse appears good to a visual inspection, see if the power light comes on when the radio is turned on. If not, I would first check the fuse while it is in circuit, using a digital multimeter. You should read the same voltage on either side of the fuse with respect to ground. If not, the fuse is defective even though it appears fine.
If the fuse is good and the power light does not come on when you turn-on the radio, check the remote turn-on lead from the head unit. It should be delivering about 12 volts to the turn on input terminal of the amplifier. No voltage would indicate that the turn-on circuit from the head unit has failed. You can disconnect it and connect the amplifier's turn-on input terminal to a 12-volt source and the amp should turn on. This will confirm that the amplifier is fine and the head unit needs service.
If the amplifier comes on with the head unit but there is just no sound, then there is a possibility that the output circuit of the head unit has failed. Here is where I have difficulty, because how the head unit is connected would lead me down the corrections of several paths. If the RCA leads from the head unit are connected to the input of the amplifier, and you have no speakers connected to the head unit speaker leads, try hooking a spare speaker directly to one of the head unit's speaker leads. My bet is that you will have no sound, indicating that the output circuit is defective. This usually is packaged with an unusual smoky smell just about the same time that the music first quit.