A very old school friend of mine, Waz, (as in we go back a long way rather than that he himself is ancient) and I decided that we wanted to see the flavour differences for pour over which arise as a result of grinder burr geometry.
This was a fun day, mainly because Waz is a great friend, but also because both grinders were originally purchased by me. Waz took over the Lyn Weber HG-1 grinder many years ago. It's the biggest hand driven grinder you'll likely ever see and the hand grinding mechanism powers a set of 83 mm Mazzer conical burrs. These are the very same burrs which sit at the heart of the Mazzer Robur, the most commonly used commercial grinder in coffee shops in Australia. The Robur is a beast.
Pitted against the HG-1 was my own KafaTek Monolith Flat, an 80 mm flat burr grinder from a wonderful grinder manufacturer based in Seattle (https://www.kafatek.com/). I maintain that Kafatek makes the very best grinders in the world.
Given that I purchased both grinders I feel that any inherent bias /preference arising from whether the grinder is mine or not is minimised (but clearly not completely eliminated!). We decided to make pour over with both grinders using the same pour over equipment and methodology. We got very lucky in that on the very first attempt the two pour over draw down times were within one second of each other!
The taste difference was clear to both of us. The flat burrs produce clearer, cleaner, sweeter, and juicier pour over. The pour over coming out of the conical burr HG-1 is fine, and if I were served it at a coffee shop I'd be completely happy. However, compared side-by-side to the Kafatek flat burr, there is a noticeable difference and both of us preferred the flat burr profile.
As always with matters of taste buds, your mileage may vary.
To hear about a coffee podcast recommendation click here
To understand cross modal effects on perception click here