What kind of amp do I need for 2 subs?

Answered by Jarrod Smith

To determine the kind of amp you need for two subs, it’s important to consider the power requirements of the subs and the impedance configuration. The power requirement will depend on the RMS (Root Mean Square) rating of the subs, while the impedance configuration will determine the final load the amp needs to handle.

First, let’s consider the power requirements. A general rule of thumb is to divide the total RMS power handling of the subs by the number of subs to get the recommended power per sub. In this case, since you have two subs and a 500 watts RMS amp, each sub will want about 250 watts RMS. So, you’ll be looking for subs that are rated for 250 watts RMS or more.

Next, let’s discuss the impedance configuration. Impedance is the electrical resistance offered by the subwoofers to the amplifier. It is usually measured in ohms (Ω). The two common types of subwoofers are Single Voice Coil (SVC) and Dual Voice Coil (DVC). SVC subs have a single set of terminals, while DVC subs have two sets of terminals.

For two subs, a final 2-ohm load can be achieved with either two SVC 4-ohm subs or two DVC 2-ohm subs. To wire two SVC 4-ohm subs to a 2-ohm final load, you would connect the positive terminal of one sub to the positive terminal of the other sub, and the same for the negative terminals. Then, you would connect the remaining positive terminal to the positive terminal on the amp and the remaining negative terminal to the negative terminal on the amp.

If you opt for two DVC 2-ohm subs, you have more wiring options. One option is to wire each sub’s voice coils in series, resulting in a 4-ohm impedance per sub. Then, you would wire the two subs in parallel, resulting in a final 2-ohm load. Another option is to wire each sub’s voice coils in parallel, resulting in a 1-ohm impedance per sub. Then, you would wire the two subs in series, resulting in a final 2-ohm load. Both wiring configurations will provide a 2-ohm final load to the amp.

Now that you understand the power requirements and impedance configurations, you can choose an amp that is suitable for your setup. Look for an amp that can deliver at least 250 watts RMS per sub at a 2-ohm impedance. Make sure to consider other factors such as amplifier efficiency, features, and brand reputation when making your decision.

It’s worth mentioning that personal preferences and specific requirements may vary. It’s always a good idea to consult the manufacturer’s specifications and recommendations for both the subs and the amp you are considering. Additionally, seeking advice from experienced car audio professionals or enthusiasts can provide valuable insights and recommendations based on their own experiences.

When looking for an amp to power two subs, consider the power requirements of the subs (aim for at least 250 watts RMS per sub) and the impedance configuration (either two SVC 4-ohm subs wired in parallel for a 2-ohm load or two DVC 2-ohm subs wired in series or parallel for a 2-ohm load). Choose an amp that can deliver the required power at the desired impedance and consider other factors such as efficiency, features, and brand reputation.