In the rapidly evolving landscape of artificial intelligence, two companies stand out as prime candidates for explosive long-term returns: SoundHound AI (SOUN) and Duolingo (DUOL). Both are leveraging AI to dominate high-growth sectors—voice technology and digital education—while operating within total addressable markets (TAMs) poised for multi-decade expansion. For forward-thinking investors, these stocks represent a rare combination of innovation, scalability, and strategic positioning.
SoundHound AI: Pioneering Voice Commerce and Enterprise AI
SoundHound AI is redefining how humans interact with machines through its voice and conversational AI platforms. The company’s Polaris multimodal foundation model—a proprietary AI capable of processing voice, text, and visual data—positions it as a leader in the $17 billion voice AI market, projected to balloon to $50 billion by 2031.
Strategic Market Positioning
SoundHound’s revenue surged 217% year-over-year in Q2 2025, reaching $42.7 million, driven by partnerships with automotive giants like Hyundai, Mercedes-Benz, and Honda. These collaborations are not just about in-car voice assistants; they’re unlocking a $35 billion in-vehicle commerce market. For example, SoundHound’s voice commerce pilots with quick-service restaurants like Chipotle and Red Lobster allow drivers to place orders hands-free, blending convenience with monetization.
The company’s Amelia 7 agentic AI platform is another growth engine. By automating customer service workflows for enterprises, SoundHound is capturing a share of the $1.2 trillion global customer service market. Its recent acquisition of Amelia AI and integration of Vision AI—which combines visual perception with conversational AI—further diversifies its offerings into sectors like healthcare and retail.
Scalable Revenue Model
SoundHound’s business model thrives on recurring revenue from enterprise contracts and usage-based pricing for voice commerce. With a $140 billion TAM and a $1.2 billion addressable backlog, the company is scaling across verticals while maintaining a 58.4% non-GAAP gross margin. Despite current losses, management anticipates adjusted EBITDA profitability by year-end 2025, a critical milestone for long-term credibility.
Duolingo: AI-Driven Ed-Tech with a Global Reach
Duolingo, the language-learning giant, is transforming education through AI-powered personalization. While it’s best known for its gamified language apps, the company’s MAX subscription service—which uses generative AI for real-time conversations with virtual tutors—has become a game-changer.
Strategic Market Positioning
Duolingo’s TAM spans the $7 trillion global education market, with a focus on the $203 billion online language learning segment. Its AI-driven approach, including features like Video Call with Lily (a virtual assistant for speaking practice), has driven a 37% year-over-year increase in paid subscribers to nearly 11 million. The company’s 40% year-over-year growth in daily active users (DAUs) versus 24% for monthly active users (MAUs) highlights its ability to convert casual users into loyal customers.
Duolingo’s freemium model is a masterclass in scalability. While 80% of users opt for the free version, the MAX subscription generates 70% of revenue. The company also monetizes through in-app advertising, leveraging machine learning to optimize ad content for learners. With a 13% net margin and $878 million in cash on a debt-free balance sheet, Duolingo is already a highly profitable business.
Scalable Revenue Model
The company’s AI-driven personalization allows it to expand beyond language learning into subjects like math, chess, and coding. This diversification taps into the broader $203 billion ed-tech market, where AI is expected to drive a 31.2% CAGR through 2030. Duolingo’s ability to scale without significant infrastructure costs—its cloud-based platform supports 128 million monthly active users—makes it a compelling long-term play.
Why These Stocks Are Undervalued
Both companies operate in sectors with explosive growth potential but are currently undervalued relative to their TAMs.
SoundHound AI trades at a forward price-to-sales (P/S) ratio of 4.5x, well below industry peers like Amazon (10x) and Google (12x). With a $5.12 billion market cap and a $140 billion TAM, the stock has significant upside if it achieves EBITDA profitability and expands into voice commerce. Duolingo trades at 20x sales, a premium to its 13% net margin, but its $15 billion market cap is dwarfed by the $7 trillion global education market. As AI personalization drives higher retention and subscription growth, the stock could justify a $100 billion valuation within a decade.
Investment Thesis
For investors seeking exposure to AI-driven growth, SoundHound AI and Duolingo offer complementary opportunities:
– SoundHound AI is a high-risk, high-reward bet on the voice AI revolution, ideal for those comfortable with early-stage tech plays.
– Duolingo is a more mature, cash-generative business with a clear path to expanding its AI-powered education ecosystem.
Both companies are leveraging AI to scale revenue models in markets with decades of growth ahead. While SoundHound’s path to profitability is uncertain, its strategic partnerships and technological edge make it a compelling speculative play. Duolingo, on the other hand, offers a more conservative bet on a proven business model with AI-driven tailwinds.
Conclusion
SoundHound AI and Duolingo are not just beneficiaries of the AI boom—they are architects of it. By dominating their respective TAMs through scalable, AI-first strategies, these companies are positioned to deliver explosive returns for investors who recognize their potential early. For those with a 5–10 year horizon, both stocks represent compelling buys in a world where AI is reshaping every industry.