If you are a music lover and you are thinking about setting up your own audio system, speaker impedance is often a very important consideration. In this article, we will be discussing 6 ohm and 8 ohm speaker – should you go with 6 ohm or 8 ohm speakers?
The fact is, impedance does not determine sound quality. Once your amp is capable of handling the power required by the speakers, impedance doesn’t matter. However, a 6 ohm speaker will pull more power than 8 ohm speakers and may put too much demand on your amp if the amp isn’t powerful enough.
If you have a low power amp, it is better to go for a higher impedance speaker, in this case, 8 ohms. If you have a powerful enough amp, it should be able to drive a 6 ohm speaker effectively.
Moreover, no speaker has the same impedance at all frequencies. This is why the only way to accurately answer this question is by knowing the impedance curves of the speakers.
Let’s get into more details about electrical impedance and 8 ohm vs 6 ohm speakers,
So, What Is Electrical Impedance?
To better understand electrical impedance, we have to refer to the extent or level of resistance to the flow of current that an electronic component exerts.
The degree of resistance observed in an electrical device is known as its impedance. It is measured in ohms and symbolized by omega (Ω).
And, What Is Speaker Impedance?
Before we are ready to talk more about whether 6 ohms is better than 8 ohms or vice versa, we have to understand speaker impedance – what it means and how it affects the audio performance of a speaker.
Speakers make use of drivers. The speaker drivers contribute to the general speaker impedance and will therefore determine to what extent or how much current the speaker will resist.
Speakers with a lower impedance or ohms rating will therefore resist lesser current and so require more power while those that have higher ohms rating have more resistance to the flow of current and so require less power.
This means that speakers with lower ohms ratings draw more current from receivers compared to those with higher ohms ratings. As a result, a 6-ohm speaker, which is considered a much more “power-hungry” speaker taxes your audio receiver or amplifier much more compared to any other speaker with a higher impedance such as an 8 ohms speaker.
Then, if lower impedance speakers are more power-hungry, why should manufacturers still be getting more of them to the market? Let’s dig deeper to understand what it means to label speakers as either 4 ohms or 8 ohms.
Why Are There Different Impedance Ratings For Speakers?
The most commonly used amplifiers are rated 4 ohms and 8 ohms speakers and there are many arguments about whether 4 ohm speakers are better than 8 ohm speakers.
Because most amps and receivers will only support speakers with similar impedance ratings, speaker manufacturers produce speakers with similar ohms ratings to be able to match their products with other audio electronics available in the market.
Generally, if you connect a 4-ohm speaker or lower to an amplifier with a higher impedance rating, there is an increased risk of ruining the amplifier hot or causing damage.
It is therefore important that speaker ratings are matched with those of amplifiers to avoid damaging the amplifier circuits. Besides, doing this is more likely to result in poor sound quality as a result of increased distortion.
8 Ohm Vs 4 Ohm Speakers
As we already mentioned, speakers with lower impedance ratings will draw much more power from the amplifier compared to those with higher impedance levels.
A 6-ohm speaker, therefore, requires more power and will draw more current from an amp than an 8-ohm speaker to yield a similar loudness of sound.
This means if you have a low power amp, a 8 ohm speaker is less likely to bow it than a 6 ohm speaker, and a 8 ohm speaker will likely perform better. This is because it is less likely to struggle for power.
This current and impedance relationship occurs between resistance, current, and voltage in electrical circuits where, for any particular voltage, a lower resistance or impedance means a higher current. This is ohms law.
On the other hand, power is a function of current and voltage. The higher the current, the higher the power. Therefore, if you want to provide more current to the speaker, the amplifier to which the speaker is connected must have higher wattage or power rating.
Amplifiers are rated just the same way as we rate speakers. We, therefore, have 4 ohms, 6 ohms, 8 ohms, and many more amplifier output impedance ratings. These are meant to be matched with speaker impedance ratings for maximum performance.
For example, it is ideal to run 8 ohm speakers on 8 ohm amps and receivers, but you can also run OK to run 6 ohm speakers on 8 ohm amps or receivers if you don’t drive the system too hard.
Therefore, if you have a 4-ohm speaker, you will need to connect it to 4-ohm amplifier output. A 6-ohm speaker requires a 6-ohm amp and an 8-ohm amp an 8-ohm speaker and so forth.
This speaker-amplifier matching is very important as it helps both electrical devices to operate optimally and be able to deliver maximum audio quality.
Usually, there are more cons than pros when amplifier and speaker impedances are mismatched.
It causes sound distortion which leads to poor sound quality and introduces more chances of damaging the circuits of the amplifier. The problem is more aggravated when you listen to loud music because of the increased power demand.
So Which Is Better, 6 Ohms Or 8 Ohms?
Now that you understand how speaker impedance affects their interaction with amplifiers, separate them in terms of which one is better.
However, as already mentioned, the amount of ohms or impedance ratings of a speaker is just a value that generally determines how much current the speaker draws from an amplifier and not how much sound it delivers nor the quality of sound.
The quality of sound given by a 6-ohm speakers and 8-ohm speakers is therefore expected to vary considerably depending on the various speaker drivers used in both.
The Impedance Curve, What It Means
It is true that the sound quality does not directly depend on speaker impedance. As a characteristic of the speaker, power amps should therefore be in a position to handle it. However, because speakers operate at very different frequencies, no single speaker will have the same ohms value at all frequencies. For instance, an 8-ohm speaker will sometimes be 5 ohms or sometimes even much lower.
Looking at the speaker impedance curve, it is clear that speakers, whether 6 ohms or 8 ohms, play at very variant impedance levels while at different frequencies. This, therefore, means that depending on the frequency, the impedance of an 8 ohms speaker for instance has chances of falling below 8 ohms and even more chances of rising well above that.
If for a vast majority, the impedance does not fall below 8 ohms, the speaker is said to have a “nominal impedance” of 8 ohms. This value is therefore just the average and not a fixed impedance value for any given speaker and only means that the speaker will not draw a constant electrical current from the receiver during operation.
Do 8 Ohm Speakers Sound Better?
A 6-ohm speaker consumes more electric power from an amp than an 8-ohm speaker to produce the same sound loudness level. So, if your amplifier has a high impedance, 8-ohm speakers can sound better than a 6-ohm speaker. However, if the amp has an impedance of between four and eight ohms, there might be no difference in volume if the two speakers have the same sensitivity rating. Speakers with higher sensitivity produce louder and better sounds.
Are Higher Ohm Speakers Better?
A lower impedance speaker, like a 6-ohm speaker, is more power-hungry than a higher impedance one. So, higher ohm speakers reduce the risk of damage, require less energy, and are more efficient.
Can You Mix 6 And 8 Ohms Speakers?
It would be best to use speakers with the specified ohm shown on the amp’s rear panel. Some amplifiers provide a range, such as 6 to 8 ohms. If yours does the same, you can mix the speakers without any issue. If the amp has an impedance of 8 ohms, you can mix the speakers without turning up the volume too high. Otherwise, you might damage the 6-ohm speakers.
How Many Watts is a 6 Ohm Speaker?
The figure “6” on your speaker represents the average impedance. So, the speaker’s impedance can range from 4 ohms to 8 ohms, depending on the volume and file type. If the speaker were strictly 6 ohms, the watts would be 145. If it were 8 ohms, it would be 109 watts.
The factors mentioned among many others such as sound imaging affect the quality of sound a speaker delivers and not speaker impedance.
It is therefore not easy to make an express conclusion as to whether a 4 ohm or 8-ohm speaker is better as it is the general opinion of the listener and depends on the many factors mentioned.
Norvan Martin is the founder of BoomSpeaker.com. He is a professional Electronics Engineer and is passionate about home theater systems and AV electronics. BoomSpeaker was created as an online hub to share his knowledge and experiences as it relates to home theaters and home audio electronics.