Jeff wrote:"#2" -- A 5-6% change in the depth of the bed will change things a bit, but not by, say, a factor of two.

It depends on the coffee and the hardware. Certain combinations of coffee, basket and shower screen can go from ristretto to bloccato on a 1g dose delta. Some coffee & hardware combos have a ±0.2g window.

cafeIKE wrote:...Certain combinations of coffee, basket and shower screen can go from ristretto to bloccato on a 1g dose delta. Some coffee & hardware combos have a ±0.2g window.

Bloccato...I hadn't heard that term applied to espresso till now but think it's perfectly descriptive. Thanks!

Pressino wrote:Are you using a spouted or naked PF? It may be easier to see the true color changes during extraction with a naked PF.

It's a naked PF.

Thanks to everyone for the discussion. I've found some local roasters that I'm going to try.

Since you're in Portland, go to a Market of Choice and buy Spella's Espresso. They roast on Wednesdays and fresh batches are usually on the shelf by Friday, often sold out by Monday. You can also get it at Spella's Cafe on SW 5th and Washington, of course. From talking to the baristas at the cafe over the years, the shot parameters are 14-16g depending on weather and age of the bean pulled with 197 degree water. I forget what the output is, but their shots tend toward ristretto so I'd guess no more than 25g out.