Pressure profiling an espresso extraction. It’s modifying the pressure during an extraction to change the flow rate of brew water through coffee—an advanced brewing feature found in commercial grade machines from companies like La Marzocco, Synesso, and Slayer Espresso.
For home espresso enthusiasts pressure profiling is next level control. In the right hands, it has the potential to tease out the best flavors a particular coffee has to offer. Hey espresso heads, Marc from Whole Latte Love here. Today I’ve got an in-depth look and feature review of Rocket Espresso’s R Nine One. We’ll pop the hood and go inside the machine for a look at components and how they work, have results of performance testing including steaming, I’ll pull shots using different pressure profiles, I’ll get into why you might choose the R Nine One over other machines with similar capabilities and have a quick look at a plumbable water filtration system—really a must for any machine at this level—that prevents scale while providing the mineral level required for best flavor.
It was a little less than a year ago, prior to it going into production, that I first saw the R Nine One at the specialty coffee expo in Seattle. Andrew Meo, owner/founder of Rocket took me through the machine and its capabilities. About three months after that our team visited Rocket’s domestic and commercial production facilities in Milan, Italy. There, we got some more details and tested it out for a day. Now even though Rocket considers this a domestic machine—albeit a premium one—it is produced in their commercial facility and that makes sense. Moving on, in December Andrew and Rocket technician Mateo came to our service facility in the U.S. to train our tech department staff on the R Nine One.
I’ve been playing with this machine for about three months. Before I get to the detailed technical specs, let’s consider what makes this machine stand out. First, there’s really no other machine with a saturated group at this price. Then throw in the pressure profiling and some other features I’ll get to in a minute and you’ve just gotta have a look. Now if you know machines you are probably saying, "hey Marc, what about the La Marzocco GS3 MP?" Well it’s a fine machine no doubt about it, but the R Nine One costs less than a GS3. And one big important difference between the machines? Repeatability. Now on either machine you can use the paddle and do manual profiles all day long. But when you hit one that gets the best out of a particular coffee or grind on the R Nine One you can save what you did manually and have the machine repeat it for you. Now I guess on the GS3 you can try and do that—ya know carefully adjust the paddle to hit the same pressures at just the same time like you did for the perfect shot? Maybe you get close. Will you be able to repeat that tomorrow or the next day or next week? Possibly, but it’s not going to be all that easy. On the R Nine One you can run a manual profile, save it and repeat it. That repeatability is huge! In fact if you want that functionality in a La Marzocco you’ve got to move up from the GS3 to a Strada EP and that’ll set you back about 15 grand. And, one more nugget to consider: the R Nine One controls pressure by pump speed and not through a valve like the GS3. That pump control is similar to the setup in La Marzocco’s higher-end Strada.
Beyond the recordable manual mode, You’ve got 5 individually programmable pressure profiles. In these you can set pressure and time values in five steps. And, you can do that right on the machine. No need to USB connect and use a web app for programming.
So the basics. The saturated group is connected to a 1.9 liter boiler. The steam boiler is 3.7 liters with a top pressure around 1.6 bar. Both boilers have 1600 watt elements under PID control—are stainless steel and larger than the boilers in a GS3. It’s plumbable or reservoir fed and includes lines for water input and the drip tray output. The pump is an ultra-reliable brushless magnetic. There’s real-time profile graphing and flow meter display during an extraction. Hot water mixing is available when the machine is plumbed and temperature adjustable so you don’t scorch Americanos. The commercial steam wand is lever operated, insulated and comes with a two hole tip. A Gicar touchscreen display controls the machine and you can set two on/off cycles for each day of the week. The machine comes with single, double and bottomless portafilters. Single and double IMS competition filter baskets and a triple basket for the bottomless portafilter. I do want to mention the warranty. Purchase the machine at Whole Latte Love and you get a best in the business three year limited warranty.
So let’s take a look at how the R Nine One operates. The ability to run a totally manual extraction is really powerful stuff, letting you watch the affects of your pressure and how it changes on flow. Then when you nail a shot you can save it and repeat it—be it today, tomorrow, next week or in a month. That repeatability? Very powerful. And then you’ve got those five pressure profiles which you can edit any way you like. So if you want a really long low pressure pre-infusion then up to nine bar and tail off the pressure to finish, or maybe a 3 bar, 6 bar, 3 bar profile. You know whatever you want, it’s on the machine, ready to go, and you can experiment with different profiles to find out how they affect flavors a particular coffee.
Starting steam pressure with the machine warm and idle is a little over 1.6 bar. Evaluating Steaming performance out of the stock 2 hole tip it took less than 14 seconds to take 6 ounces of milk from 45 degrees to our preferred finished temperature of 140 degrees. The roll is vigorous. Pressure dropped to about 1.3 bar during steaming and held there. Recovery time back 1.6 bar following steaming was about 20 seconds. To test what kind of reserve the machine had I opened the steam valve for 60 seconds and let it rip. Steam pressure dropped to about 1.1 bar. And after 60 seconds of full steam output it took about one minute for the machine to fully recover 1.6 bar. Rocket does have accessory tips available so I put those to the same tests. Here’s a look at the roll produced by each of the accessory tips and the time it took for each tip to take 6 ounces of milk to that 140 finished temperature.
It’s important to feed your machine with quality filtered water. It improves espresso flavor and can eliminate descaling maintenance. For a plumbed machine our recommended solution is a BWT filter package with pressure regulator and an optional flow meter which lets you know when it’s time to change the filter cartridge. Beyond standard particle and activated carbon filtration the BWT Bestmax Premium filter uses patented ion-exchange technology which removes scale causing calcium and replaces it with magnesium. This process maintains the mineral level required for best flavor while preventing scale build-up by reducing calcium. Scale build up is the number one cause of machine problems down the road. So very important to feed your machine with good water—for peace of mind a filtration system is required equipment on any plumbed in espresso machine.
Before I wrap things up a reminder to hang around for an extended look at the features and programming of the the Gicar touchscreen. You’ll find It’s quite intuitive, simple to operate, and presents a wealth of information. Before that some final thoughts. If pressure profiling is where you want to go. Rocket Espresso’s R Nine One is worthy of your consideration. Why? Well, the only other saturated group machine close in features and price is the GS3 and it lacks that profile repeatability. You can’t run a manual profile on a GS3, save it and repeat it. This machine has larger boilers, similar hot water mixing capabilities and I like the reliability of controlling brew pressure via the pump rather than using a restricting valve. And you can also program shots based on volume with the R Nine One. Now, if you’ve got comments or questions fire away down in the comment section and I’d be happy to get you detailed answers. I’m Marc, thanks for reading.