Which Specs Matter When You Compare Semi-Automatic Espresso Machines?

Published September 24, 2026 · By the Espresso Shortlist editors · Prices and specs as of that date, from the pages under Sources

Summary

Three lines on the spec sheet change the morning routine most: how the machine heats, whether you can set the brew temperature, and what the pressure figure refers to. Across five semi-automatics sold in the U.S., the stated heat-up runs from 3 seconds on the Breville Bambino to 5 to 7 minutes on the Profitec GO in its fast heat-up mode, and temperature control runs from nothing you can set to a PID. The 15 bar on three of these spec sheets is the pump's rating, and Breville and Gaggia both state 9 bar for the shot itself.

Five machines, one spec sheet

Machine	Price	Heating	Stated heat-up	Brew temperature you can set	Pressure on the spec sheet
Breville Bambino	$299.95	ThermoJet	3 seconds	None listed	15 bar pump; low-pressure pre-infusion, then 9 bar extraction
Gaggia Classic Pro E24	$549	Single brass boiler, 3.5 oz	Not stated	None listed	15 bar Ulka pump; OPV set to 9 bar
Profitec GO	Not on Profitec's page	Single brass boiler, 0.4 L	5 to 7 min in Fast Heat-Up mode	PID, for brewing and steam	Pressure gauge; brewing pressure set at the expansion valve
KitchenAid KES6551	Not on the product page	"Fast-heating technology"	Not stated	Low, Medium, High	Pressure gauge with an "Ideal Espresso range"
De'Longhi La Specialista Arte Evo EC9250M	$699.95	Thermoblock	Not stated	3 profiles with Active Temperature Control	15 bar pump

The KitchenAid and De'Longhi grind beans inside the machine; the other three need a separate grinder.

Heat-up time and boiler size

With a 3-second heat-up, the Bambino is ready before a separate grinder has finished a dose. Breville says its ThermoJet reaches "the optimum extraction temperature in 3 seconds" and uses up to 32% less energy a year than a thermoblock. The Gaggia Classic Pro heats a 3.5 oz brass boiler that Gaggia describes as "single-boiler/dual-use," one boiler for both the shot and the steam wand. The Profitec GO's boiler is 0.4 L and insulated, and even in the mode Profitec calls Fast Heat-Up it needs 5 to 7 minutes.

The PID on the GO lets you "set the desired temperature for coffee extraction and steam," and its display counts the shot in seconds. The Arte Evo offers three infusion temperature profiles, and the KitchenAid has a Temperature button with Low, Medium and High. The Bambino and the Classic Pro list no brewing-temperature setting at all.

What "15 bar" means on these machines

Breville puts it plainly on the Bambino page: the shot "starts with low pressure pre-infusions, followed by a high pressure (9 bar) extraction process," delivered through a 15 bar pump. Gaggia's spec table lists the same pairing, a 15 bar Ulka pump with the over-pressure valve (OPV) calibrated to 9 bar. De'Longhi lists only the pump's 15 bar for the Arte Evo. Profitec gives no bar figure for the GO; its brewing pressure is adjusted on the expansion valve and read on the gauge. KitchenAid's gauge marks an "Ideal Espresso range" without a number.

Portafilter size and dose

The basket sets which accessories fit and how much coffee a shot takes. The Bambino uses a 54 mm portafilter and Breville's recipe is 18 g of coffee. The Classic Pro and the KES6551 both use 58 mm; Gaggia lists basket capacities of 7 to 18 g, and KitchenAid's basket chart gives 10 to 12 g for one shot and 17 to 19 g for two. Profitec's page lists a two-spout portafilter with one-cup, two-cup and blind filters but gives no diameter.

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Sources

We have not tested these products. Specs, prices, stock and terms are as published on these pages on the date above and can change; check the manufacturer or retailer before you buy.