How To Understand Sound Comparisons

Our sound comparisons let you hear how the headphones truly sound, but you have to know the disclaimer.

All headphones sound a bit different. And the best way to know the difference is to hear it. That’s why we create sound comparisons between a neutral sound and the headphones we’re reviewing.

Here’s the disclaimer:

Most headphones won’t sound exactly the same as in comparison videos because your phone speakers, your laptop, or PC speakers change the sound of the video.

Since your listening sound quality won’t be 100% accurate, the real sound signature is slightly different.

Nonetheless, it gives you a good example of how a specific pair of headphones sounds in comparison to a neutral signature.

And, in our opinion, it’s a much better representation of sound quality than mere explanation in words.

You’re welcome to use our comparisons to make better buying decisions, but keep in mind the limitations of such representation.

Now, making a comparison is a far more meticulous process than you might think. More on this below.

In this article, we describe:

• How to accurately listen to our sound comparisons

• What equipment we use

• How we make a headphone recording

• How we correct the frequency response of that recording

How to Understand Sound Comparisons?

The original track represents neutral audio.

By comparing the original track to a recording of the tested headphones, you can hear what areas differ.

You can hear the changes in bass, midrange, and treble compared to the original track. And it gives you a good idea if that’s something you want in your headphones.

For most accurate representation, use neutral (or at least close-to-neutral) headphones or speakers.

How Not to Understand Sound Comparisons?

Listening to the comparisons with non-neutral headphones will affect your opinion.

Using heavily colored headphones, you will hear differently from what our comparison is trying to show.

Every audio track is mixed and mastered using neutral-sounding equipment. The latter represents a reference point.

Let’s say the headphones we’re testing have a bass boost. However, headphones that you use to listen to our comparison also have a bass boost.

Since we corrected our recording to sound just like testing headphones, we’ve also boosted lower frequencies.

Consequently, when you listen to our recording of a bassy headphone with your bassy headphones, the comparison will end up sounding extremely bass-forward.

That’s why to get an accurate picture of how our headphones sound, you have to use flat headphones yourself.

Take sound comparisons with a grain of salt

We’re doing our best to make comparisons as accurate as possible. However, we can’t vouch they’re 100% accurate.

Human hearing isn’t pitch-perfect, so there might be some discrepancies between our recording and the headphone’s sound.

What Equipment do We Use to Make Sound Comparisons?

MiniDSP H.E.A.R.S.

These are artificial ears with a microphone at the end of both ear canals. They simulate a human head with molded earlobes (or pinna). 

It’s worth noting that they aren’t an industry standard. An entire torso with a head can cost $10.000 or more. However, H.E.A.R.S. can still offer a great insight into how the headphones sound.

Neutral Headphones

For tweaking our sound recordings we use Sennheiser HD 6XX and Ollo Audio S4.

Both headphones are very well-balanced and widely used in studios. They’re an excellent pick for correcting audio recording’s frequency response.

Audacity

It’s free software with many useful tools to record and edit audio recordings. We use Audacity for both recording and later frequency response tweaking.

Since Audacity doesn’t support real-time EQ adjustments, we also use AIMP 3 music player and its built-in EQ.

How Do We Record Sound?

• First, we place headphones on our MiniDSP H.E.A.R.S. Bigger over-ears don’t require that much adjustment. On the other hand, we need to change ear tips on earbuds to get the best results. We usually use the smallest ones.

The seal has to be perfect since it can affect bass response.

• To reassure if seal is correct, we start recording audio through Audacity and play some music via headphones.

• By looking at the graph and listening to a recording afterward, we can ensure that the seal is optimal.

• At this point, we open a new project in Audacity, start recording again, and playing a pre-selected song that is in all our comparisons.

A song for sound comparisons has to be diverse, with quiet and loud passages, different instrumentation, and natural vocals. The one that we use (“Coming Home” (feat. Ollie Wade) by Niwel & Altero) ticks all the boxes, making it easier for you to hear what headphones are capable of.

• We also ensure a quiet testing environment since sensitive microphones could pick up any movement or ambient noise.

• After the entire song is over, we stop recording and save an audio recording in the best quality (MP3-320kbps).

How Do We Create the Comparisons?

After making a recording, it sounds a bit dull and nothing like the headphones we’re testing.

Therefore, before publishing the final comparison, we have to correct the recording by tweaking its frequency response.

Correcting Frequency Response

That is the part where we need to go old-school and use our ears to correct the recording of our headphones.

We found that the easiest way to do it is to:

• play the original song through our testing headphones from a smartphone (to hear how they truly sound)
• listen to a headphone’s recording on a laptop with our neutral headphones (and making tweaks)

That way, we can quickly shuffle between headphones we’re testing and neutral headphones to make corrections.

• We play the headphones recording with AIMP 3 music player. A built-in equalizer helps us hear every small adjustment in real-time while a song is playing in the background.

• When we think we nailed tuning, we apply the same EQ adjustments in Audacity.

• Later, we try listening to our tuned recording to see if it really sounds like tested headphones. If not, we continue with fine-tuning.

Why We Correct Each Recording?

The purpose of MiniDSP H.E.A.R.S. is to make frequency response graphs. Since built-in microphones aren’t calibrated, each artificial ears come with calibration files.

Software for making frequency response graphs, like REW (Room EQ Wizard), can read these calibration files. Audacity, on the other hand, can’t, which means none of Audacity’s recordings are calibrated.

Why Use Neutral Headphones?

Neutral headphones are an excellent reference since they don’t color the sound. In addition, they reassure us that our recordings aren’t going to sound completely off in a final sound comparison.

If we used headphones with no bass instead of neutral ones, we would compensate for the loss and add too much bass to the final recording.

The latter wouldn’t truly capture the sound of tested headphones, making our recording disingenuous.

The same goes for you, the listener. Without using at least balanced headphones (or speakers) to listen to our sound comparisons, you might form a wrong opinion on our tested headphones.

Creating Video

When we’re happy with our tuning, we prep everything to make a video sound comparison.

1. In Adobe Premiere Pro, we import both the original track and newly tuned recording.
2. We cut both tracks in places with smooth transitions so that the listener can clearly hear the difference.
3. After everything is done, we upload the video to YouTube, so you can experience the real audio of reviewed headphones.

Here’s the link to our HeadphonesAddict YouTube channel.

Peter Susic

From a childhood fascination with sound, Peter’s passion has evolved into a relentless pursuit of the finest headphones. He’s an audio expert with over 5 years of experience in testing both audiophile and consumer-grade headphones. Quote: “After many years, I can confidently tell which headphones are good and which are terrible.” Find his honest opinion in his reviews.