For your subwoofer to work optimally and make your car shake, the accessories must be matched to the subwoofer. You should also be aware that serious mistakes and untuned accessories can cause the subwoofer or cables to start burning and, in the worst case, the insurance company may cancel the insurance because you have attached the fuse incorrectly to the K […]
Structure & combination of the components
A battery, radio and speakers should usually already be installed in the car. You only have to pay attention if the battery can withstand the new load or if it will die. This depends very much on the power of your power amplifier, for stronger ones you should in any case install a powerful car battery. Above 1,000 Wrms a second battery or a powerful starter battery is mandatory.
The cabling from battery to radio is already in place. Only a second power cable is laid from the positive pole of the battery to the power amplifier or, if necessary, capacitor. Be careful when connecting the cable and battery! Clamps are suitable for a good connection. These do not come loose due to vibration and are strong enough not to melt under strong current.
We have reviewed and compared car batteries for each car class: To our car battery review
With a car radio, a great deal is a matter of taste: the height (1 din or 2 din), the inputs (USB, CD, Aux etc.), features (navigation system, hands-free etc.) and the design (lighting, colour etc.). The only thing it should have is a separate output for the subwoofer, the sub-out. This allows the subwoofer to be controlled directly and you can change the settings from the radio.
We have reviewed and compared car radios: To our car radio review
If you still have the factory-installed speakers in your car, you should definitely check if the quality fits. You can do this by turning up the volume on your car radio. If the car speakers start to hiss or overload, you should replace them. Otherwise, the subwoofer will give you a good sound, but the mid and high frequencies will sound bad. You should also check the insulation of your car doors, if they are not good enough, the sound experience will unfortunately remain poor.
We have reviewed and compared suitable car speakers: To our car loudspeaker review
In order to operate the subwoofer, several types of cable are required, which we will now discuss in detail:
In most cases it is suitable to take a suitable cable set
Power cable: The power cable ensures that the output stage is supplied by the battery. Most often the cables are made of copper or aluminium (aluminium is also known as eco-cable). There are also cables with a silver layer, mixtures etc. Nevertheless, copper is of higher quality and is the most suitable, because it is more flexible and has a 30% better conductivity than aluminium (more power or less power consumption), but unfortunately it is also much more expensive. If you don’t have to save money, you should definitely not start here!
The diameter of the cables depends on the power of the output stage. A minimum for the cable thickness is 20 mm² (too thin power cables can cause flickering of the headlights) From 500 W rms there should be a 35 mm² cable and from 700 W rms a 50 mm² cable.
Cinch cable: The Cinch cable is the connection between the car radio and the power amplifier. The RCA cable should not be laid near the power cable, as the power cable is a source of interference and can cause noise in the sound. It is best to lay the RCA cable on one side of the car and the power cable on the other. A shielded RCA cable with a length of more than 5 m is recommended for purchase.
Remote cable: A minimal current flows through the remote cable, which only sends pulses when the radio is switched on or off.
Speaker cable: The speaker cable* sends a small current to the subwoofer, which eventually causes the diaphragm to vibrate and produce a sound. Up to 1,000 Wrms can be achieved with a 2.5mm² cable, everything above that with a 4mm². Nevertheless, it is advisable to use a 4mm² cable beforehand to be on the safe side.
A second reason for flickering headlights can be the absence of a capacitor. It charges as soon as current is available and releases the charged current at a power peak. This flattens the peaks and relieves the battery. A further advantage is that the powercap can release current faster than the battery, allowing the output stage to develop its full power.
An unwritten rule is that a powercap is mandatory from 500 Wrms, below that it is not mandatory but still recommended. A rule of thumb is 0.1 F [Farad] per 100 Wrms. This means that for a power amplifier with 1,000 Wrms we need a powercap with 1 F.
The cabling of the powercap is between battery and power amplifier, it is wired in parallel. When installing the powercap you have to take care that the capacitor is charging very fast. Therefore you should let the capacitor charge before you put in the fuse. The easiest way to do this is to use the enclosed bulb, hold the legs in the holder and let it charge. As soon as the bulb is no longer lit, the fuse can be inserted without a spark. Alternatively a ceramic resistor (10 W and 10 Ohm) can be used. The only difference is to hold the resistor for 1 minute because there is no signal for full charge.
Discharging the capacitor is particularly important if the vehicle ever needs maintenance. To do this, remove the fuse and stop the bulb at the + and – pole of the powercap. Continue until the bulb goes out. Alternatively stop the resistor for 1 minute.
The power amp breathes life into the subwoofer, without it the sub would not have enough power to move the diaphragm. The tuning between the two components is especially important, because if the power amp’s output is too weak, the sub can’t develop its full power, or if the power amp is too strong, it will kill the sub within the first few months or, in the worst case, immediately. Therefore both should have approximately the same power (Wrms).
When connecting, you can either plug the subwoofer into 1 channel or you can connect it over 2 channels and make a bridge. This has the advantage that the power is increased 4 times and the impedance is halved (e.g. 2 outputs with 100 W each, if you bridge them now, the sub has a L […]
Last but not least there is the subwoofer. If you only have a diaphragm or a subwoofer, you can’t do much wrong with the speaker cables. Be careful when wiring 2 diaphragms, if the poles of the speaker cables are connected opposite each other, the diaphragms work against each other and no sound can be heard. Therefore always check twice and do not turn up the volume too fast when adjusting the power amplifier.
Safety first also applies to installation! If you don’t want the subwoofer to fly straight through your car in an accident, it should be fixed, either screwed on or with tension straps*. An adhesive strip or a non-slip surface is not enough in an accident! Once the subwoofer flies across the car, it is subjected to insanely high forces. In a frontal crash at 50 km/h alone, an object weighing 20 kg suddenly has the effect of 800 kg. At 70 km/h even like 1,200 kg! This applies to many areas
We have reviewed and compared subwoofers: To our subwoofer review
Here a video from ADAC: Safety first!