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Ratio Eight review: A stunningly beautiful coffeemaker saddled with a sky-high price

There's just one button to kick off brewing.

Tyler Lizenby/CNET

Essentially a pre-infusion mode meant to rid excess carbon-dioxide from freshly roasted coffee, a few devices such as the Bonavita BV1900TS and Behmor Brazen Plus offer similar features. Both these machines, however, give you more control over the function, such as toggling pre-soak on or off (Bonavita) or setting how long it will run (Behmor).

After a brief pause, the Ratio Eight then launches into its full "brew" mode, indicated by another white light. Here, the machine picks up the flow tempo and drips a steady shower of hot water over the grounds until brewing is complete, finally illuminating its "ready" light.

Magnets help the Ratio Eight detect the presence of the carafe.

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The Eight automatically detects the presence of its glass brewing vessel, too, thanks to magnets hidden in both the machine's base and the carafe's bottom. It's a welcome safety feature, designed to prevent the product from starting the brewing process without a receptacle to catch it. Unfortunately, it also means you can't use other brewing vessels other than those built by Ratio.


I'm happy to say the Ratio Eight stuns with more than just its gorgeous design. This machine is an excellent drip coffee brewer as well. Using the recommended brewing ratio of 40 ounces of water to 2.3 ounces (65 grams) coffee (coarsely ground) run through a no. 4 paper filter yielded delightfully delicious results.

I can vouch that the coffee the Ratio Eight brewed was exceedingly delicious.

Tyler Lizenby/CNET

Not only was the coffee (brewed from basic Costco House Blend beans) rich and complex, it had an enjoyably clean (not bitter) finish. That's an impressive feat, given how easy is to overbrew this medium-dark roast to a stringent result with a harsh aftertaste. Reflectometer readings confirmed the Eight's pour over prowess. My brew had a TDS (total dissolved solids) percentage of 1.2. This translates to an extraction percentage of 18.9 percent, which is right on the money according to the SCAA (Specialty Coffee Association of America). The group defines the ideal cup to have a TDS between 1.15 and 1.35 percent.

The Eight can use paper filters or the special Able Kone filter shown here.

Tyler Lizenby/CNET

I'm sure much of the reason for the Ratio's enviable brewing performance is that the machine heats its water nice and hot. I measured the water temperature in the filter via thermocouple at from 192 to 195 degrees Fahrenheit (88.8 to 90.5 Celsius) within the first minute of the brew cycle. At the two-minute mark brewing temperature usually climbs to 197 degrees F (91.6 C), where it stays with robotic-like precision for the duration of the 7-minute brew time (total, counting the 45-second bloom mode).

It's also worth mentioning that a virtually identical amount of coffee grounds brewed using the optional Kone filter created an even more flavorful beverage. With a higher TDS percentage of 1.36, the resulting coffee was exceptionally rich, almost silky smooth in texture, and it had an extremely long finish. I tasted no bitterness to speak of either.

Keep in mind that while the Ratio Eight's glass carafe is easy on the eyes, it comes with a big trade-off. Unlike the Technivorm Moccamaster KBT-741 and Bonavita BV1900TS which come equipped with thermal carafes that keep coffee hot for several hours, the Eight's glass pitcher cooled to below 150 degrees Fahrenheit (66 Celsius) within just 30 minutes.


I applaud Ratio's pluck and daring to bring to market a coffeemaker as polished as the Eight. With its hand-blown glass, ceramic nickel, aluminum and wooden design elements, it's unlike any automatic drip brewer I've ever used. The machine is also an excellent coffee brewer that consistently whipped up drip java that's just as tasty as the big boys on the block, namely the aforementioned Technivorm and Bonavita models.

Despite all its strengths, however, I can't recommend buying the Ratio Eight over its rivals. With a jaw-dropping $580 price tag (which jumps to $640 if you factor in the Able Kone filter), you could purchase two Moccamasters. Likewise, that amount would cover three Bonavita machines. The Eight's incorrect water volume labels are also a deal-breaker and an unacceptable glitch at any price. Unless you have a burning desire to own one of the most unique coffee-making appliances ever made, your money is better spent elsewhere.

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