Alternate Filters on the Ratio Eight

Our guest contributor for this piece is Wesley Farnell, co-founder of Eight Ounce Coffee in Canada. Read on for some insights into two filters that can be used alongside a Chemex or stainless Kone in the Ratio Eight!

Unlike any other homebrewer on the market, the Ratio Eight has the unique functionality of adjusting bloom and brew cycle, based on the amount of water in the tank. This is a great feature when you want to brew less - when you want a cup just for yourself but don’t want to take the time to make a manual brew or you’re just feeling a little lazy - but don’t want to compromise a shred of quality. 

The other thought that that occurs is what if you just want to make it in your favourite pour-over brewer, but don’t want to pour? While you can use other electric coffee makers to do this, you get what you’re given when it comes to the brew cycle: either no bloom, or a bloom based on a higher volume of water: not ideal. This is where the Ratio Eight comes into its own as it will adjust the brew time based on water volume, meaning that a smaller pour-over is now possible, without compromise. Sounds good, but does it actually work well? There was only one way to find out…

I went ahead and chose our most popular brewers: the Hario V60 and the Kalita Wave. Knowing that the Ratio Eight safety feature requires you to use a Ratio carafe, I had to use the (beautiful) matching Thermal Carafe that you can buy as an addition to the Ratio Eight. I then had to make sure that the brewer would sit flat to ensure an even extraction so, after testing, I settled on the Kalita Wave 185 in stainless steel and the glass Hario V60-02 dripper. These would sit exactly flat on the carafe and gave me the best possible chance of an even extraction.


Hario V60 (left), Kalita Wave (right)

I prepared both as I usually would for each dripper using 30g of coffee at a suitable grind and 450ml water (1:15 ratio). I also made sure that the brew head was centered over the bed of coffee and then was ready to go. First I brewed the Wave and, once set up, I could have walked away and came back to a cup of brewed coffee but, on this occasion, I thought I better hang around to see what happened. Once I pressed the start button the water started to pass through the heater and the bloom began. The bloom water pulsed out: enough to nearly saturate the entire bed. I would have liked to see a little more water and I almost felt the need to swirl the brewer but I held myself back. Once the brew cycle kicked in, it processed without risk of overflow and the brew time was within usual Kalita parameters. 

Kalita Wave

I then repeated the same with the V60 and in this case, due to the shape of the brewer, the bloom seemed to be more effective and the coffee bed was entirely saturated. Again, the brew was within expected brew times of the V60. 

So the real question is how did they taste? It’s a bit unfair to test them against each other, as if you prefer the output of a V60 filter to a Wave filter, then you’ll probably stay in your usual lane - in light of this, the team were split on what they preferred. However, we also brewed the same coffee, at the same parameters, as a manual pour over to compare each like for like.

Hario V60 

And the results? While I won’t share the data (it could get boring) I will concentrate on the most important area - taste. Comparing the Kalita brews, the team enjoyed both but, when pushed, most chose the manual pour over. This is most likely due to the lack of full saturation during bloom due to the flat bottom style of the brewer. I’d recommend a quick stir with a spoon if you decide to use a Kalita to make sure all the grounds get saturated.

Kalita Wave

For the V60, it was much closer - some people preferred the manual, but it was really close and some team members couldn’t tell them apart.

Comparatively, the Ratio Eight works better for the V60 due, in part, to brewer geometry combined with how the water pours from the brew head: it tends to favour the outer holes and that definitely impacts smaller brew volumes, combined with wider coffee beds. 

Hario V60

While I want to do a lot more testing I can safely say that if you want to make your favourite pour over, and don’t have a pour-overkettle, or the time/inclination to manually pour, then the Ratio Eight is a mightily impressive alternative. It extracts well, adjusts the brewing to water volume accordingly and it looks really, really good on the counter while it’s doing it.

Hario: V60 Glass Coffee Dripper

Kalita: Wave Stainless Steel Dripper