There’s a sound that you’ve heard countless times on songs throughout the years. It appears seemingly at random, and yet sounds familiar every time it pops up. It’s embedded in the work of some of the most influential producers of hip-hop’s past and present, from Timbaland to Zaytoven—and trust me when I say you’ll know the sound when you hear it. It’s easier to just listen than it is to describe, so hit the YouTube embed below:

It’s a pitched-up voice that is singing a short note almost operatically, for around a full second. Depending on how you choose to listen, it could either be an “Ohh!” or “Oww!” or “Aaaah!” The sound is referred to as “Aaaah! (169).” The reason? That’s the description and number of the sound on the place it originally appeared, the Roland M-DC1, a device introduced in 1995.

“Aaaah! (169)” was a “patch,” or sound, made for the machine—just one of over 250 different sounds for users to experiment with. You can see the complete list here. “Aaaah!” comes in the middle of a batch of similar sounds—it’s followed immediately by “Ahoo Yell” and “Oohh!!.”

According to WhoSampled, “Aaaah! (169)” has been used in at least 135 songs to date. It’s peeked its aural head up in tracks by well-known names like Travis Scott (“3500”) and Nicki Minaj (“Want Some More”), and by rising artists like Rich the Kid (“End of Discussion”) and Maxo Kream (“Capeesh”).

One of the earliest and most distinguishable examples of the sound being used on a record is Playa’s 1998 single "Cheers 2 U." Co-produced by Timbaland and the late Static Major, who was a part of Playa, the song literally would not have existed without that sound; it’s used liberally throughout and serves as an integral part of the foundation. When I reached out to Timbaland, he said via email that Static came up with the concept. “I just pieced it together,” he said. “Just being creative. I just knew I wanted it to feel like a celebration.”

Looking back on his early use of the sound versus how it’s used presently, Timbaland said he felt the contemporary usage was inspiring to see. “I think it’s dope,” he said. “I think you can manipulate it a lot easier now.”

Easier is debatable, though the sound’s appearance is unquestionably more widespread in hip-hop today. But what the hell is it, exactly? Roland Corporation’s vice president of global marketing, Paul McCabe, explained via email that the M-DC1 synthesizer sound module was originally promoted as an instrument for dance music.

Sadly, the company doesn’t know exactly who created the sound. “In the case of the now-famous ‘Aaaah! 169’ sound, unfortunately we do not currently have access to these records,” McCabe wrote.

But that lack of knowledge hasn’t stopped Roland from programming the sound into recent keyboards and modules. The sound has also made its way into plenty of drum kits made by producers, like Lewi V Beatz, who’s worked with G Herbo, and Zaytoven, whose history of using the sound goes back as far as a decade, on mixtape tracks by Gucci Mane and OJ da Juiceman. One of the most recent examples of Zay’s use of the sound is Future’s “When I Think About It,” from BEASTMODE 2, released in July.

During a phone conversation, Zaytoven explained his introduction to the sound. “The first time me hearing it, it was in the keyboard,” he explained. “It was the Roland Fantom-S. I was making beats; I was just looking for different lil’ sounds to put in the beat. And it ended up being a sample. I don’t even want to call it a sample—it's just a sound that I ended up using in a beat. And then, after you use it once and you like it, you use it over and over again. It just started being something of a go-to sound for me. I've been using it for years.”

One of Zaytoven’s most notable uses of the sound is in Migos’ 2014 track “Add It Up.” It’s peppered throughout the song, punctuating the moments when members of the Migos turn up and employ their rapid-fire, staccato flows. Zay said the generous use of the sound just made sense to him, given his history.

“I'm a producer that, if you listen to the music that I've been producing over the years, I kind of have a sound,” he said. “Like a signature sound. That was just one of the beats where I was just like, ‘Oh, I need to throw something else in it. Let me throw the ‘Aaaah!’ in there.’ I just started using it however I felt it on the beat.”

Producer Young Mercy Beatz, who used the sound in Dae Dae’s popular 2016 single “Wat U Mean (Aye, Aye, Aye),” told me that he was directly inspired by Zaytoven’s use of the sound.

“The first time I heard this shit was in one of Zaytoven’s beats a long time ago,” he said. “Eight, nine years ago. I was trying to figure it out for the longest. I didn't find that sound till probably about four years ago. Before then, nobody but Zaytoven had that sound—that’s what it seemed like to me. When I finally got a hold to it, I was using that sound in all of my beats.”

Young Mercy Beatz explained that the sound wasn’t a necessity, but he was adamant that it enhanced his work. “It’s something about that noise that brings a certain sound to the beat,” he said. “With the ‘Wat U Mean’ beat, it would've been still cool, but when I added that sound to it, that shit just amped it all the way up."

When I asked Young Mercy Beatz if he had placed the sound in any other songs, he explained that he had to retire it. “I had to stop using that shit,” he said. “I became a fiend for it. I really had to go to rehab and sit in the room for 30 days and not hear that sound to get it out my system.”

By now you must be wondering why I haven’t mentioned arguably the most recognizable instance of the sound in a song: “Dilemma” by Nelly and Kelly Rowland. That high-pitched intonation is the first voice we hear on the track, right before Kelly starts singing about loving and needing Nelly. As the song goes on, the sound takes a backseat to more fleshed-out production, but it remains the star of the show. “Dilemma” was produced by Grammy-winning musician Ryan Bowser—who told me he didn’t use the “Aaaah! 169” sound while creating the track.

“A lot of people thought that was a sample,” he explained. “It was actually just me going into the mic room and just trying different things that worked vocally. It was funny to hear people say that was a sample. No, that's me.”

When I brought up “Cheers 2 U,” released four years prior to “Dilemma,” and asked Bowser if he was familiar with it, his answer was direct: “I had never heard it.” It’s worth mentioning that when played back to back, the vocal used in “Dilemma” and the “Aaaah! 169” sound, which Timbaland confirmed using in “Cheers 2 U,” are strikingly similar.

I asked Paul McCabe from Roland about the likelihood of Bowser’s claim ringing true. “The simple answer is that it is possible,” McCabe wrote. “One of the important aspects of electronic music production is sound design. While some producers will use the standard sounds that come with an instrument (known in our world as ‘presets’), others will create some or all of the sounds in a track from scratch. A skilled producer that has a talent for sound design could conceivably create a near-perfect copy of almost any sound they hear, including the famous ‘Aaaah! 169.’”

The sound, whether created organically as Bowser suggests, or programmed via a Roland device or producer drum kit, has become an essential part of hip-hop. It continues to be used widely by established producers and under-the-radar beatmakers alike, and the manipulation of it remains varied, unpredictable, and, above all else, unfailingly entertaining.

Zaytoven, perhaps the sound’s best-known champion, contends that his production—and lots of other street anthems as well—would be borderline somber without “Aaaah! 169.”

“It just brings a brightness to it,” he said. “You know what I mean? You can have something that's dark, a dark-sounding beat, and then you add them ‘Aaaahs’ to it and it just brightens it up. It brings that exciting feeling to the beat.”