The vertical drama industry is booming. Originally a niche, smartphone-only, soapy TV series, it has transformed quickly over the past few years, generating over $1.3 billion in the US as part of a booming multi-billion-dollar global ecosystem.
Driven by 90-second episodic cliffhangers, leading vertical drama platforms like DramaBox and ReelShort boast daily views for a Gen Z audience, which spends roughly five hours a day on their phones. The watch time and engagement metrics are growing steadily, with most episodes gaining 100 million views per episode. Over the past five years, the vertical drama industry in the US proves it is a competition to traditional streaming platforms like Netflix and Prime.
Alongside the actors, producers and directors in this growing industry niche, the booming vertical drama industry is providing jobs for sound engineers like Minjia Du, an industry innovator who bridges the gap between technical precision and emotional storytelling.
Minjia Du is a versatile force across the complete audio pipeline, maintaining a practice that spans location recording, dialogue editing, sound design and re-recording mixing. Having films selected at the 30th LA Shorts International Film Festival, including supervising sound editing on The Last Coin and sound mixing on Fortune House, alongside recognition at the Glendale International Film Festival, her expertise covers high-stakes narrative projects, major commercial campaigns and viral vertical drama series. Du has mastered both production sound and post-production, establishing herself as a rare end-to-end perspective that elevates sound from the background utility to the driving force of vertical dramas.
"Vertical drama compresses not only screen space into the 9:16 format, but emotional time," Du explains. "In a 60-to-90-second episode packed with dramatic turns, sound isn't simply decorative—it helps control the pace and makes every narrative shift register immediately."
Designing audio for a mobile-first format presents distinct creative hurdles. "Because vertical dramas embrace a heightened style, music and sound effects must build an emotional logic that makes exaggerated events feel authentic," says Du. "However, restraint remains critical. If every revelation features the loudest possible impact, the audience becomes numb. A sudden absence of ambience, an isolated breath, or a subtle Foley detail can often make the following beat much more powerful."
Working across several high-profile vertical drama series on major distribution channels like DramaBox and DramaWave, including projects that have reached over 211 million views and held #1 rankings, Du has refined an audio workflow tailored for demanding timelines. "A 60-episode vertical drama series may require complete sound design within two or three weeks,” she said. “Managing that turnaround while maintaining cinematic quality requires extensive preparation, precise organization, and an intuitive understanding of emotional pacing."
Dialogue clarity is key to Du’s job as a sound engineer, especially when the sound is being listened to on a smartphone. "Viewers listen through earbuds, phone speakers, or in noisy public spaces," Du notes, explaining how her role as a sound engineer for vertical dramas ranges across production sets and post-production studios: She either captures the audio of actor performances live on set, or works behind-the-scenes in post-production, shaping the music, ambience and sound effects around the actor’s dialogue, making sure it is clear enough. “When I work post-production, I am continuously testing mixes across studio monitors, headphones, and mobile devices to ensure complete clarity," she notes.
Beyond technical execution, the narrow vertical aspect ratio opens unique creative opportunities. "The restricted frame reveals less surrounding environment, so sound expands the world beyond the image—signaling an approaching threat, a distant crowd, or the psychological distance between characters sharing a close-up," she adds.
Viral vertical drama series like Wild Ride with the Dangerous Kian, sound design serves as narrative punctuation. "Dynamic sound design isn't about keeping the soundtrack constantly intense," said Du. "It is about controlling where the audience's attention goes from one second to the next."
On set, Du’s responsibilities extend far beyond microphone placement. As a Production Sound Mixer, she evaluates noise conditions, plans microphone coverage, manages wireless systems and protects dialogue while coordinating with the camera, lighting, costume and directing departments. In post-production, she applies that same awareness of performance and editorial needs to create coherent acoustic spaces and dynamic arcs.
"For crucial encounters, I build miniature dynamic arcs within an episode,” she said. “Grounding a scene with physical details before stripping away ambience allows a key line to stand out clearly. Alternating between microscopic details—such as breathing or fabric movement—and sweeping musical shifts gives even a 60-second clip the feel of continuous cinematic development."
Since low frequencies can lose their impact on mobile speakers, Du projects danger and tension through texture, vocal space, and rhythm, rather than relying solely on deep bass. "Sound captures attention by promising change," she adds. "Audiences stay engaged because the soundtrack signals that something vital is about to happen, and then delivers that payoff."
Du's holistic command of both sound production and post-production sets her work apart in fast-paced filmmaking environments. "I do not view location recording, sound design and final mixing as isolated stages," she notes. "Anticipating post-production needs while recording on set prevents costly fixes later. Preserving performance nuance at the source protects the actor's truth, which no amount of post-processing can recreate if lost."
To give high-pacing episodic series the refined quality of premium television, Du establishes a clear hierarchy between high-impact audio effects and subtle character moments. "Attention-grabbing sounds mark irreversible story turns, while quieter details reveal what those turns mean to the characters," she explains.
A door slam or gunshot drives the sound of what we see onscreen, “but the emotional truth lives in the aftermath,” said Du, whether it’s a trailing breath, a shift in room tone, or a brief silence.
"By maintaining consistent acoustic spaces and tailored sound textures across episodes, the series feels like a unified cinematic world,” she said. “Premium quality isn't about making every detail bigger; it's about having the confidence to know which moments should command the room and which should remain intimate."
