Rocket R NINE ONE Espresso Machine - With Pressure Profile Control

the Wendougee DATA S is a top contender.

It combines all the hallmarks of a true high-end machine:

• High-Quality Build & Engineering – Premium construction with refined components and commercial-grade internals for long-term durability and precision performance.

• Stable Gear Pump – Commercial-grade pump delivers smooth, quiet, and highly consistent pressure with real-time adjustments for perfect shot curves.

• Thermal Stability – Dual boilers (0.8 L brew / 1.8 L steam) and a saturated group head keep temperature rock-steady throughout extraction.

• Precision Profiling – The E-Bar app lets you manually adjust, save, and share custom pressure/flow profiles with real-time feedback.

• Pro-Level Versatility – Nicknamed the “Mockingbird machine” for its ability to accurately replicate virtually any espresso profile.

• Rave Owner Feedback – Praised for its exceptional control, consistency, and repeatability—often outperforming other high-end prosumer machines.

This makes the Wendougee DATA S not just a strong choice, but arguably one of the best machines available for serious pressure profiling.

Here’s why the Wendougee DATA S stands out as a top-tier espresso machine—especially if you're looking for advanced pressure profiling capabilities:

1. Gear Pump with Real-Time Pressure Feedback

Equipped with a commercial-grade gear pump, the machine ensures quiet, smooth, and highly stable pressure delivery—a foundational requirement for accurate pressure profiling. The pump continuously self-adjusts to maintain the target pressure curve.

2. Dual Boiler System with Saturated Group Head

A dedicated 0.8 L brew boiler and 1.8 L steam boiler, coupled with a saturated group head, deliver outstanding thermal stability. This ensures that temperature remains consistent throughout the shot—critical when manipulating pressure curves.

Farmhouse Kitchen and Bath

3. Manual Flow & Pressure Profiling with Smart App Control

You can fine‑tune extraction curves manually using the included app or tablet interface. The E‑Bar app offers real-time feedback, diagnostics, and the ability to save, share, and recall custom pressure or flow profiles—offering both precision and convenience.

Eight Ounce Coffee

4. Deemed a “Prosumer King”

Enthusiasts at Bella Barista dubbed the Data S the “Mockingbird machine”, emphasizing its ability to replicate any espresso profile with exceptional accuracy, thanks to its refined engineering and gear pump.

5. Positive Owner Feedback

Actual users report that the Data S offers unparalleled control and consistency, often outperforming other high-end prosumer machines in terms of repeatability and shot quality.

There are two variants: the Data-S (tank only) and the Data-S-DL (tank + direct connection). The tank version is suitable if you don't have a water supply or want to be mobile. The DL variant allows a fixed water connection, which contributes to stability and less refilling. The internal components are identical

the Data S in about 5-10 minutes. This is faster than many E61 machines. After heating, it is advisable to let it stabilize for a few more minutes for maximum consistency.

Included as standard are a portafilter with wooden handle, single and double filter trays, a blind filter for backflushing, a tamper and a tablet holder. The tablet itself may vary by retailer. Vellutto.com provides a two-year carry-in warranty in the Netherlands, Belgium, Germany, Austria.

Pre-order prices on Vellutto.co.uk are around €3,100-3,700. That's higher than a Lelit Bianca V3 (€2,300) but lower than premium machines like the Rocket R Nine One (€6,000+) and Slayer Single Group (~€8,000+). Given the dual boilers, gear pump and app integration, the price is competitive; keep in mind additional costs for the Milo 2 grinder and Themis scale.

Pressure profiling involves changing the pressure on the coffee grounds during extraction. Traditional machines deliver a constant 9 bars, but varying the pressure can affect flavor and body. Low pressure pre-infusion gently saturates the puck and reduces channeling; a rising phase extracts flavor components and a controlled drop can reduce bitterness. The Data S lets you program and store these phases

Flow profiling controls the amount of water per second rather than the pressure. As the coffee puck changes resistance during extraction, the pressure will rise and fall to maintain a constant flow rate. This can lead to more even extractions. In flow mode, the gear pump adjusts its speed to maintain the set flow rate. The principle is similar to what the Decent DE1+ does.

It depends on the coffee and your goals. Pressure profiling is intuitive for users familiar with lever machines; it allows clear pressure phases. Flow profiling can simplify dial-in because the pump automatically corrects for minor grinding errors. For a light Ethiopian coffee, for example, you can start with 2 ml/s for 10 seconds and then increase. For a dark roast, you can choose a pressure curve with gentle pre-infusion at 2 bar, peaking at 8 bar and dropping to 5 bar. Experiment and save successful profiles.

The current software requires you to choose between pressure or flow control for each profile. A combination within one shot is not documented. Possible firmware updates may change this.

In the E-Bar app, profiles can be stored in the cloud, so practically speaking, there is a lot of space. For offline storage, we recommend contacting the manufacturer.

The gear pump, PID-controlled boilers and sensors follow the programmed curve. During extraction, the app displays real-time graphs of pressure or flow rate; if deviations occur, the controller adjusts pump speed. Recalling the same profile reduces variability. Consistency also depends on grind and tamp; integration with the Milo 2 grinder and Themis scale helps manage these variables

Yes. The E-Bar community lets users upload and download profiles. So beginners can start with recipes from experienced baristas. Success does depend on grind adjustments and water quality.

Only in combination with the Bookoo Themis scale. This scale detects the desired weight and stops extraction. Without a scale, time or volume is used.

The machine features a cool-touch steam pipe and hot water pipe.

Yes. Like other machines, the Data S has a three-way solenoid, which removes pressure at the end of extraction and allows backflushing. Regular backflushing with detergent is important

Most of the control is done through an external tablet or smartphone, which simplifies the internal electronics. Which makes it more reliable because the electronics inside the machine are simple and easy to replace

Er bezieht sich auf die reibungslosen Extraktionsgrafiken auf dem Tablet. Die App zeichnet Druck- und Durchflusskurven ohne Schluckauf, sodass die Benutzer in Echtzeit sehen können, wie sich ihre Einstellungen auf den Schuss auswirken. Dieses visuelle Feedback macht die Schnittstelle im Vergleich zu einfachen Druckmessern attraktiver.

The app displays charts and offers tutorial profiles. Beginners can load existing profiles or download community recipes. Advanced features such as drawing curves and linking devices take some getting used to. It pays to invest time in learning how to work with the app

If applied correctly. Variable pressure can improve the body and balance of a shot; flow control helps reduce channeling and bring out sweeter flavors. Machines like the Slayer Single Group are famous for their low-flow pre-infusion. The Data S offers similar control with digital reproducibility and at a lower price.

Choose a mode (pressure or flow). In pressure mode, you can start with a pre-infusion at 3 bar for 8 seconds, followed by 8-9 bar for 20 seconds and a drop to 5 bar. In flow mode, you can maintain 2 ml/s for 10 seconds and then 3 ml/s. Adjust the grind rate until the shot reaches the desired weight within 25-35 seconds. The E-Bar app shows the curve so you can make adjustments. Experiment and monitor puck preparation.

The Data S is intended for fresh coffee with standard 58 mm filter trays. Perforated (pressurized) trays can be used, but then pressure/flow profiling is less useful. Use a medium-fine grind and check the shot for time or volume.

Rinse daily with water and use backflushing detergent weekly. Clean and rinse the steam pipe after each use. Descale every 3-6 months depending on water hardness. The maintenance program in the app can provide reminders. The manual is not publicly available, so specific instructions are unknown. For warranty claims, the machine should be sent to the dealer

The gear pump suggests long life and the stainless steel boilers are corrosion resistant, And the high-quality components give the machine pretty good reliability

It is wise to use filtered water with 50-100 ppm TDS and balanced alkalinity. If connected directly, a filtration system is essential to prevent scale formation.

The machine uses standard 58 mm filter trays, compatible with aftermarket trays and tampers. A blind filter for backflushing is included.

No. The Wendougee Data S works with any grinder, but with the Milo 2, grinding factors are automatically adjusted to the chosen profile. If you already have a good grinder, you can adjust manually.

Gear pumps are quieter than vibration pumps; the Data S produces an even hum. Noise from steam and grinding is louder than the pump.

Without tablet, it measures 29 cm wide, 50-52 cm deep and 37 cm high. With tablet, the height is about 46 cm. Keep in mind the depth and space for the portafilter.

Vellutto.nl offers two-year carry-in for EU customers

Yes. The E-Bar app receives updates and can add new features. Firmware updates for the machine itself are loaded through the app. Follow manufacturer instructions to avoid problems.

• Inconsistent shots due to pump variation → The gear pump delivers stable pressure with real-time feedback, reducing shot-to-shot variation and enabling reproducible profiles.

• Limited control over extraction → Users can choose between pressure profiling or flow profiling and adjust the pump in small increments, creating pre-infusion ramps, pressure plateaus, and declining curves. Profiles can be saved and shared via the E-Bar app.

• Learning curve with manual machines → The E-Bar interface shows live graphs of pressure, flow, and temperature and lets you save favorite profiles; when connected to the Milo 2 grinder and Themis scale, a guided dial-in workflow is created.

• Temperature instability → Two independent PID-controlled stainless-steel boilers maintain brew and steam temperatures separately, providing thermal stability comparable to commercial machines.

• Slow warm-up times → The Data S heats up in about five minutes, so you can start faster.

• Noisy or inconsistent pumps → The gear pump runs quieter than vibration pumps and offers smoother pressure changes.

• Limited integration with grinders/scales → When paired with the Milo 2 grinder and Themis scale, grind size and extraction parameters are automatically synchronized, and the shot stops at the target weight.

• No community sharing → The E-Bar app lets users download and share extraction curves via a community platform, which supports learning and experimentation.

• Hard to clean → The machine has programmable cleaning cycles and a three-way valve for easy backflushing; the steam boiler can be drained via a front access valve (common practice for dual-boiler machines; specific manufacturer details unknown). Unspecified details about routine maintenance and parts availability are noted.

• Concerns about footprint → At 29 cm × 50 cm, the Data S is narrower than many commercial-style machines, making it suitable for home kitchens.

Typical home machines offer fixed pump pressure or manual flow control via a lever, making shots difficult to reproduce. The Data S supports two modes: pressure profiling and flow profiling. The gear pump delivers constant pressure and responds quickly to adjustments, allowing you to design and save extraction curves in the E-Bar app. The machine has two stainless steel boilers with PID control for commercial temperature stability. Integration with the Milo 2 grinder and Themis scale creates a workflow where grind rate, flow/pressure and yield are automatically synchronized

Yes. EU sellers ship to the Netherlands, Belgium, and Germany. The average processing time is 3-5 business days for shipping; if an item is out of stock, delivery can take ~5-15 business days once it is available. Shipping is via major EU couriers (PostNL/DPD/DHL/UPS). Shipping policies may vary slightly from seller to seller, so please check the product page at checkout.

vellutto.nl

Purchases made by consumers in the EU are covered by EU consumer protection legislation and therefore have a two-year legal guarantee against manufacturing defects. Retailers' policies reflect this standard.