Exploring the Ratio Four Series Two: A Coffee Enthusiast's Choice for Testing New Brews

As WIRED's lead coffee writer, I have a deep appreciation for the diverse world of coffee, from espresso to cold brew. However, my heart remains with a steaming mug of drip coffee, which has evolved significantly due to technological advancements. The Ratio Four coffee maker, now in its second generation, epitomizes the essence of coffee for me, capturing the fresh aroma of ground beans in its purest form.

My journey with filter coffee began during my teenage years in India, where I first embraced the intense, unsweetened brew. This preference for black coffee followed me back to Oregon, where I endured subpar drip coffee in diners and office breakrooms. It was not until later that I realized drip coffee could be as indulgent as espresso.

The transformation in drip coffee quality is partly due to technological innovations. Previously, home drip coffee makers struggled to produce excellent coffee, with few exceptions like the Moccamaster. My perspective changed with the rise of third-wave coffee shops in Portland, such as Stumptown Coffee and Heart Coffee Roasters. These cafes introduced me to the aromatic purity of light-roast coffee, a craft long perfected in Scandinavia.

Despite these revelations, achieving similar flavors at home remained challenging until the advent of a new generation of drip coffee makers. These machines, inspired by cafe pour-over techniques, feature agitating showerheads, precise temperature control, and a "bloom" phase for optimal extraction. Brands like Bonavita and Oxo have led a revolution in home drip coffee.

Among these innovations, the Ratio Four small-batch brewer from Portland's Ratio has become my go-to machine for testing new coffees. As someone who frequently tests coffee and espresso machines, my kitchen setup changes often. However, the Four consistently remains on my counter due to its suitability for my routine. It is designed for brewing small batches of eight or 16 ounces, allowing for rich extraction without the need for constant adjustments.

The Four brews a full 20-ounce batch in just over five minutes, with a patient bloom cycle that ensures even extraction. It delivers a full-bodied flavor, revealing the deeper nuances of the coffee. While the Technivorm Moccamaster offers precision, the Four excels in uncovering hidden flavors. It is reliable and repeatable, producing consistent results with the same coffee and grinder settings.

However, the Four is not without its quirks. Its white model is prone to coffee stains, requiring regular cleaning with Urnex Cafiza to prevent off flavors. The absence of a drip stop means occasional drips need to be wiped from the base. Additionally, the Four is designed for immediate consumption, lacking a thermal carafe. Its serving temperature mimics pour-over, which I prefer, as it prevents the coffee from cooling and oxidizing before reaching my ideal drinking temperature of 150 degrees Fahrenheit.

Ultimately, the Ratio Four is my preferred tool for exploring new coffee beans. Paired with a precise flat burr grinder like the Mazzer Philos, it allows me to experience the distinct flavors locked within each bean. The chocolate notes taste authentic, and the fruit flavors are vivid. This experience is a far cry from my first strong cup in Jaipur, yet it aligns with my teenage aspiration to appreciate coffee in its purest form.