Nine Lives Coffee Roasters brews espresso at 6 bar pressure and 5–6g/s flow rate — significantly below industry standards of 9 bar and 12–15g/s. Combined with precision burrs and the Weber Workshop 16g Unibasket dosed to ~17g, this approach produces cleaner, more even extraction from lighter-roasted specialty coffee. This guide explains the setup, the reasoning, and how to apply the same principles at home.
Why Specialty Espresso Is Brewed Differently
Standard espresso uses 9 bar of pressure and extracts in approximately 25–30 seconds. This approach works reliably across a wide range of coffees and grind qualities. It is forgiving, fast, and consistent.
Specialty espresso — particularly lighter roasts with fruit, floral, and sweetness-forward profiles — benefits from lower pressure and slower flow. Here's why:
Lower pressure extracts more gently, requiring higher grind uniformity to achieve even extraction. When grind uniformity is high, the result is cleaner flavour separation, less channelling, and better preservation of the delicate notes that specialty coffee is roasted to express.
Higher pressure compensates for inconsistent grinds. For coffee where those subtle notes matter, compensation is not the goal — precision is.
The NLCR & Our Coffee Bars Espresso Setup
Pressure and Flow Rate
| Parameter | Our Setting | Industry Standard |
|---|---|---|
| Brewing pressure | 6 bar | 9 bar |
| Group head flow rate | 5–6 g/s | 12–15 g/s |
| Consistency | 3+ years | — |
Equipment
| Component | Specification | Location |
|---|---|---|
| Machine (primary) | La Marzocco GS3 MP, full manual control, group saturated | The Alley Penang |
| Machine (secondary) | Reconfigured compact setup | Moonshine Cakes & Coffee |
| Grinder (milk coffee) | Mahlkonig e65s / Anfim Pratica + LeBrew 65mm Hyperburr | Both bars |
| Grinder (black coffee) | Mazzer Super Jolly VP Pro (upgrading to SSP HU 64mm) | Both bars |
| Basket | Weber Workshop 16g Unibasket | Both bars |
| Dose | ~17g (slight overdose) | — |
| Headspace | ~7mm | — |
How Pressure Affects Extraction
At 9 bar: Water pushes through the coffee puck with higher force. This extracts quickly and tolerates inconsistent particle distribution as pressure pushes through gaps. The resulting cup is full and intense, but can suppress finer flavour notes.
At 6 bar: Water moves more gently. Grind uniformity matters more — without pressure to compensate for inconsistencies, the grind has to be even for extraction to be even. When it is, the result is cleaner flavour, better-defined acidity, and the fruit and sweetness notes of lighter-roasted coffee are preserved rather than compressed.
How Flow Rate Affects Puck Integrity
Standard flow rate (12–15g/s): Water enters the puck quickly. Effective and efficient, but higher velocity increases the risk of channelling — where water finds the path of least resistance through the puck and extracts unevenly.
5–6g/s flow rate: Slower saturation. Water contacts the puck more evenly before full pressure is applied. Combined with high-uniformity burrs, this allows even extraction across the entire puck surface — the flavour in the cup reflects the whole bed, not just the channels.
The tradeoff: slow flow and low pressure require a grinder capable of producing consistent particle size. Inconsistent grinds at these settings produce uneven extraction more noticeably than at 9 bar.
The Role of the Basket and Dose
The Weber Workshop 16g Unibasket is used with a ~17g dose — a slight overdose by basket spec. This fills the basket to approximately 7mm of headspace before tamping.
Consistent headspace controls how evenly water distributes across the puck surface when the portafilter locks in. Too much headspace and water disperses unevenly before reaching the coffee; too little and the puck is compressed against the shower screen.
No puck screen is needed at 7mm. The basket and dose together do the work.
Choosing the Right Grinder for This Approach
Low pressure and slow flow demand high grind uniformity. The grinder is the most important variable.
For milk coffee: Mahlkonig e65s or Anfim Pratica with the LeBrew 65mm Hyperburr. The Hyperburr is a precision burr engineered for high uniformity at fine grind settings — the grind required for slow, low-pressure extraction.
For black coffee: Mazzer Super Jolly VP Pro, transitioning to the SSP HU 64mm. Black coffee espresso is less forgiving — without milk to integrate the cup, extraction clarity and flavour separation are more exposed.
Applying This at Home
Most home espresso machines do not allow pressure or flow rate adjustment without modification. If yours doesn't: focus on grind uniformity and puck preparation instead.
What you can always control:
- Grind consistency: use a burr grinder with a tight particle distribution
- Distribution: stir or Weiss Distribution Technique (WDT) before tamping to break up clumps
- Tamp: level and consistent, not heavy — more pressure on the tamp does not improve extraction
A well-prepared puck at 9 bar will outperform a poorly prepared one at any pressure. The variables you can control are always more important than the ones you can't.
Frequently Asked Questions
Why do specialty coffee roasters use lower brew pressure? Lower brew pressure (6–7 bar) extracts more gently than the standard 9 bar, preserving delicate flavour notes — fruit, florals, sweetness — that higher pressure can flatten. It requires higher grind uniformity to achieve even extraction, but when grind quality is high, the result is a cleaner, more complex cup.
What is a good flow rate for espresso? Standard espresso flow rate is 12–15 grams per second. Specialty setups often use 5–8g/s. Slower flow rates allow more even puck saturation, reducing channelling. The right flow rate depends on grind uniformity — slower flow requires a more consistent grind.
What espresso machines can adjust pressure and flow rate? Machines with E61 group heads, La Marzocco Linea Mini/GS3 MP, Decent Espresso DE1, and similar prosumer/commercial models allow pressure profiling and flow rate adjustment. Entry-level machines typically operate at a fixed 9 bar without modification.
What is the Weber Workshop Unibasket? The Weber Workshop Unibasket is a precision espresso basket designed for even water distribution and extraction. It is used at Nine Lives dosed to ~17g (above the 16g spec) to maintain optimal headspace without a puck screen.
What is the LeBrew 65mm Hyperburr? The LeBrew 65mm Hyperburr is a precision replacement burr for the Mahlkonig e65s and Anfim Pratica grinders. It produces high grind uniformity — essential for the low-pressure, slow-flow extraction approach used at Nine Lives.
What espresso blends does Nine Lives use for this setup? Underdog Blend (Myanmar + Ethiopian) for milk-based espresso, and 111 Blend (double Ethiopian) for black espresso and Americanos. Both are available at ninelivescoffee.co.
Shop Nine Lives Espresso Blends → Underdog Blend — milk. 111 Blend — black. RM 55 / 250g.
Nine Lives Coffee Roasters is a specialty roastery based in George Town, Penang, Malaysia. Available online at ninelivescoffee.co.