What Does OHMS Mean in Terms of Subwoofers and Amps?


For many years, people have been confused about amps, watts and ohms. Most of this confusion is regarding subwoofers and amps used with musical instruments. It’s worth mentioning that ohms and watts are entangled in a set of mathematical formula, which link them closely together. Therefore, when one of them changes, the other one undergoes a change too. A better understanding of the concept of ohms helps you enjoy better music volume, bass and tone.

It’s important to understand that amps provide the required electrical pressure in a circuit. OHMS measure the load or resistance against this pressure. On the other hand, watts measure the amount of power released as work. Thus, using one of the math formulas, an amp providing 100 watts of power through a standard 4-ohm speaker products 200 watts with a 2-ohm speaker. The primary reason is that it’s easier to push the reduced load.

What Does OHMS Means in Terms of Subwoofers and Amps?

SubwoofersHow a person loads an amp determine the average amount of power out. However, there is a trade off. When the impedance or the value of ohms is lower, more power is pushed. Moreover, more heat and higher distortion is generated. Excessive heat caused by the process shortens the life of the amp.

When you want the best performance, it’s better to purchase a high powered amp. It should be loaded with 4 ohms. You shouldn’t purchase a lower powered amp and unnecessarily force it to product more power with 2 ohms. It not only shortens the device’s life, but also leads to bad sound quality. Another major trade off is price. An amp that is able to produce higher power at 4 ohms tends to be more expensive.

In order to make subwoofers produce best sound quality, they need to be powered by an amp whose standard RMS output rating is close to the total of RMS ratings of all subwoofers. It’s worth mentioning that when you need to run three subwoofers with 300 RMS ratings, you require 900 watts RMS power.

OHMS in SubwoofersUnderpowered subwoofers neither play loud nor sound good. When you try to increase the input to compensate for power, the amp ends up sending distorted or clipped signals, which may damage the subwoofers. In some cases, you can overpower the subwoofers. However, the signal needs to be distortion free.

The end goal is always to have the amp send maximum power to subwoofers, which can easily handle it. Many experts recommend using different wiring options. This optimizes the impedance to get maximum power from particular subwoofers and amps. It’s considered to be the most effective way to run a subwoofer/amp system.

Before applying a specific load to an amp, its capability needs to be considered. You shouldn’t just hook a subwoofer and amp at any power input. Most manufacturer’s give precise indications about the amp’s minimum impedance requirements. It’s worth mentioning that almost every amp can drive a standard 4-ohm load. Similarly, most amps can work well with 2-ohm loads on every channel, but not when these channels bridge together. Some amps can even drive a very low load, i.e, 1-ohm.