2-Ohm Vs 4-Ohm Subwoofer: Which is Right for Me?

Can’t choose between the 2-Ohm vs 4-Ohm subwoofer? No need to panic! At Audio Curious, we melt down the basics to help you choose the right subwoofer for your car.

Sometimes, it may get a little bit tricky to navigate the technical jargon when choosing what impedance is suitable for your car subwoofer (especially if you’re new to electronics and car stereo). As a result, car owners will often find themselves in a dilemma while figuring out what hits harder 2 ohm or 4 ohm? To answer this question, you must first understand what electronic resistance is and how it applies to car speakers.

You also need to understand that no matter the resistance, your chosen car subwoofer should have a balance between the cost, power consumption, efficiency, and, more importantly, the final output in crisp, clear, unmatched quality sounds. So, read on to unveil the differences between a 2 ohm or a 4 ohm subwoofer.

Understanding the Basics: Volts, and Amps in 2-Ohm Vs 4-Ohm Subwoofer

Your car stereo consists of several components interconnected with wires running to and from the amp, the speakers, the head unit, among several other connections. To fully understand what’s the difference between 2 ohm and 4 ohm speakers, we must first delve deeper into the power specifications (in volts, amps, and ohms).

Your head unit, amp and subwoofer communicate via electrical signals, which vary in current and voltage. The voltage in your car subwoofer is a measure of how hard the signal is, and the current denotes how much power gets shared inside the wired connection. The higher the voltage, the louder the sub. This also applies to the current – the more the current, the louder the sound.

The relationship between the current and voltage is measured in Ohms. In car speakers, we use the term speaker impedance to refer to the measure of the coil’s total resistance to the electric current flow in the presence of an audio signal. Speaker impedance affects the amplifier’s output.

For instance, if you have 14V 2 Ohm speakers, you get 7 amps of current. According to Ohm’s Law, a decrease in resistance denotes an increase in current. This suggests that 4 ohms subs would generate about 3.5 amps at 14 volts while the 2-ohm subwoofer takes 7 amps at the same voltage. Halving impedance doubles the maximum output while doubling impedance reduces the output by half.

The output from your amp is measured in watts, and the 2 Ohm subwoofer has more watts than a 4 Ohm subwoofer. Technically, the subwoofer that generates more output wattage produces a louder sound than the one with lower wattage.

More About 2 Ohm Subs

When buying a subwoofer, most people will look at the advertised output power, which may not necessarily be the real figure after all. In fact, it might not even be the most important determinant for loudness. Instead, you might want to look at the impedance (speaker resistance measured in Ohms), which will give you a more accurate picture of what to expect.

2 Ohm subwoofers do not carry much resistance. This means that your sub will produce a louder sound at lower resistance but produce lower sound at a higher resistance. In simpler terms, 2 Ohm subwoofers are louder than 4-ohm subwoofers.

Advantages of 2 Ohm Subwoofers

Running a 2 Ohm subwoofer bears several advantages for the car owner. First of all, a 2-ohm subwoofer allows you to send less voltage for the amount of output from your amplifier. This means less voltage and better output from your 2 Ohm subwoofer compared to a higher resistance 4 Ohm subwoofer.

Secondly, they produce louder sound due to less resistance. If you’re working under a tight budget, the 2 Ohm subwoofers are an excellent option to go with since you’ll get some good sound for your money.

Disadvantages of 2 Ohm Subwoofers

Subwoofers with lesser resistance tend to produce low-quality sounds than higher resistance. This happens because, with low power consumption, subwoofers are much more likely to produce poor quality sound.

More about 4 Ohm Subs

4 Ohm speakers are widely used in many car brands. They have higher resistance but do not require an amp as powerful as the 2 Ohm speakers. Remember, a subwoofer operating with 4 Ohms impedance does not mean it’s constant. Impedance varies with the current frequency. This means that the 4 Ohms you see labelled on the subwoofer is only a summary of the average impedances the subwoofer is designed to work with.

Technically, a 100W 4-ohm subwoofer should draw in 100W from the 4-ohm amp. At the same time, a 2-ohm sub would draw about 200W from the same amp. This shows that 4 Ohm subwoofers draw less current compared to the 2 Ohms. Forcing the amp to deliver more power could distort the sounds and lead to gradual amp damage.

4 Ohm Subwoofer Advantages

Do 4 ohm speakers sound better? Yes, they do. One of the main advantages with a 4 Ohm speaker is better quality sound. At higher resistance, your speakers tend to produce a more accurate and clearer sound that can be heard from some distance.

4 Ohm Subwoofer Disadvantages

Unfortunately, 4 Ohm subwoofers produce lower sound compared to the 2 Ohm subs. Secondly, the price of the components also scares away some car owners. 4 Ohm subwoofers are meant for people who are serious about their sound systems and the quality of sound they get for their money.

Learn More: What is Causing a Buzzing Sound in the Car Stereo?

Getting The Right Impedance

Are you torn between dual 2 ohm vs dual 4 ohm? It all depends on the impedance and wiring. Remember, amps are stable only to a particular impedance, so you want to get your subs in a wired connection that achieves that impedance.

At the heart of every subwoofer is a voice coil (probably the most important part of the speaker). Without it, there can be no sound. Impedance in the voice coil is measured in ohms. The lower the subwoofer’s impedance, the easier it is for an amplifier to supply power. Therefore, before buying any amp you find in the market, you need to consider its capacity. Most amps, if not all, can drive a 4 ohm subwoofer. Other amps can drive a load as low as one ohm.

If you have multiple subwoofers installed, the total impedance depends on how the subs and their voice coils are aligned together either in series or parallel. Parallel wiring means that all subs are connected in such a way that positive connects to positive and negative to negative. In a series wiring, a positive terminal connects to a negative terminal, one sub after the other.

When speakers or subs are wired in series, you get higher impedance. This can be calculated by adding their impedances together to find the total impedance. For instance, two 4 ohm subwoofers wired in series connection have a total impedance of 8 ohms. However, when subwoofers are wired in a parallel connection, their impedances are calculated by dividing the impedance of one sub by the number of subs in the connection. For example, four 4 ohm subwoofers wired in parallel have a total impedance of 1 ohm.

To get a clearer picture, you can check out this 2 ohm vs 4 ohm wiring diagram.

Verdict: Which Is Better 2ohm Or 4ohm Subs

Is 2ohm or 4ohm better? It all boils down to personal taste, what you want to achieve, price considerations, and your gear. If your main interests slide with the loudness of the sound, and louder bass, then a 2 Ohm sub will do a good job delivering the loud sound you desperately need. However, if you’re more concerned about the quality of sound rather than its loudness, then, by all means, go for the 4 Ohm speakers.

Another critical factor to consider when comparing 2-Ohm Vs 4-Ohm Subwoofer is the price range. Different manufacturers offer different prices for their gear. For instance, a 2-ohm subwoofer would range from around $50 and $200, depending on the brand. The next thing you might want to look at is the size; a 15-inch subwoofer is larger and obviously more expensive than an 8-inch subwoofer.

Avatar for Jamie K. Martin

Jamie K. Martin holds a degree in Audio engineering from Husson University, Bangor. Martin spends most of his time testing and trying the technology he writes about to ensure that he provides first-hand information to our customers from all walks of life.

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