Izzo Alex Duetto IV Plus Review: The Most Underrated Dual Boiler?
Perhaps because it has a reasonable price tag, the Izzo Alex Duetto IV doesn’t seem to get the same hype afforded by many other brands. Well, in my opinion, that is a huge oversight. This impressive dual boiler espresso machine stacks right up there with the best and comes in hundreds of pounds cheaper than many.
Does that sound too good to be true? With this review of the Izzo Alex Duetto, I’ll dig deep into the details, so you can decide for yourself. Note that this machine is no longer sold in the UK, but you should find plenty of second-hand options available.
SUMMARY: The Izzo Alex Duetto IV Plus
- Dual boiler semi-automatic espresso machine with PID temperature control
- Commercial style E61 group head with automatic pre-infusion
- Excellent build quality with useful upgrades from previous models
I will never regret buying this machine…It is quite beyond expectation. The quality of espresso has kept me out of coffee shops since day one.– Roger, Customer
The Izzo Alex Duetto IV Plus Espresso Machine Review
There are plenty of prosumer espresso machines with dual boilers and PID temperature control on the market, so what makes the Izzo Alex Duetto IV Plus stand out from the crowd? And is it the right espresso machine for you? That’s what this review is here to help you decide.
In this section, we’re going to do a deep dive into the brewing capacity, milk frothing, and build quality of this surprisingly affordable and underrated model.
Brewing Capacity – 4.5/5
The Izzo Alex Duetto IV Plus has all the bells and whistles you could want, especially at this price when it comes to brewing capacity. That includes dual boilers, a quiet rotary pump, and PID temperature control — to name just a few.
The Izzo Alex Duetto is a dual boiler espresso machine with independent PID controllers for each boiler. What does all that mean from a practical standpoint? Well, with a dual boiler espresso machine, you can steam milk and brew coffee simultaneously. But this is also true of a heat exchanger espresso machine. A double boiler with a PID controller like the Izzo Alex Duetto shines because you have exact control over the brew temperature.
Lovers of specialty coffee will attest that extraction temperature can have a strong effect on a coffee’s flavour, and different coffees extract better at different temperatures. This has been further proven through rigorous research conducted by coffee scientist Dr. Monika Fekete (1).
There’s room for more investigation, but we can conclude that a few degrees change in the temperature of the water and the grinds have a significant effect on how a shot turns out.
So the precise temperature management afforded by the PID controller in the Izzo Alex Duetto is a key feature if you like to experiment with different coffees, especially exotic single origins.
A PID controller also yields better temperature stability versus a thermostat, thanks to a constant feedback loop. This is invaluable when it comes to dialling in a perfect shot and then repeating it consistently. Because you control the boilers independently, you can turn off the steam boiler when not in use to save energy.
Let’s talk Boilers
When it comes to boilers, size matters, a bigger one means you can make more drinks in a row without waiting for it to refill. Both boilers in the Izzo Alex Duetto are suitable, with the steam boiler measuring 1.8 L and the brew boiler measuring 0.8 L. If you like to have friends over for coffee or brunch, this is a great espresso machine serving a crowd.
The brew and steam boiler are made from copper with brass end plates, a common choice for high-end machines. Copper is one of the more expensive options, but it has the best thermal properties of any material, which is why they chose it over stainless steel (2). Because of copper’s thermal conductivity, it only takes the Izzo Alex Duetto about 20 minutes to heat up, despite its hefty size.
Compared to steel, copper is also softer. That makes it better able to withstand slight changes in size due to temperature and pressure fluctuations without weakening. However, it also makes it more challenging to attach plumbing, so brass end plates are used.
And Brew Heads?
The Izzo Alex Duetto IV uses the classic E61 group head, a favorite for prosumer-grade espresso machines. This thermosiphon design cycles hot water from the boiler to the group, ensuring everything remains hot and at a stable temperature (3). This stability is aided by the big 3.6-kilo chrome-plated brass group, which acts as a heat sink.
E61 lever-operated espresso machines have an automatic pre-infusion stage, using either line pressure or residual pressure in the brew boiler, depending on whether you’ve opted to direct plumb your Alex Duetto. This low-pressure stage before extraction wets the grounds so that they settle evenly, correcting any potential imperfections in puck preparation. The result is a richer and complex brew with improved consistency. You’d be hard-pressed to find an espresso pro who doesn’t proclaim the importance of pre-infusion (4).
User-Friendliness – s4/5
Most E61 machines have a similar workflow, and the Izzo Alex Duetto is no exception. However, the Alex Duetto does have a few user-friendly features not seen in many others, which makes the overall experience of using it very enjoyable.
It’s effortless to monitor what’s going on inside the Izzo Alex Duetto.
Monitoring is crucial for making consistently great coffee. The PID controller display is located at the top of the machine, as opposed to the more common bottom corner, so that it’s easy to see and use. This visibility is particularly lovely when you’re pulling a shot, as it automatically converts to a shot timer.
Similarly, the two pressure gauges are located in the upper half of the machine. They allow you to monitor both brew pressure and pump pressure. And if you want to change the pump pressure, the valve is now more easily accessible than in previous models. All it takes is inserting a screwdriver into the side of the Alex Duetto and giving it a quick turn.
Many espresso makers force you to choose between a water tank or direct plumb. Unlike that, the Izzo Alex Duetto allows you to set up for both. You can quickly toggle ]between the easily accessible switch tucked behind the large removable drip tray. The tubing and drain kit comes with the purchase.
If you’re a fan of larger drinks, you’ll be impressed with the nearly 15 cm of clearance between the drip tray and group head, which is reduced to closer to 10 cm with the spouted portafilter inserted. This is a much-requested update to a previous version of this machine that featured a larger drip tray and less clearance.
Milk Frothing – 3.5/5
The milk frothing set-up on the Izzo Alex Duetto espresso machine is everything you would expect from a high-end espresso machine. However, it doesn’t necessarily bring anything extra special to the table.
There are separate wands for steam and hot water, fully articulated, and feature a double-wall, no-burn design. This insulated system has two benefits. It keeps the exterior of the wand from getting too hot, so you’ll have a hard time accidentally burning yourself. It also keeps milk from burning to the steam wand during steaming, making clean-up much simpler.
On the Izzo Alex Duetto, both wands are controlled by knobs rather than joysticks. Knobs are great, especially if you’re new to this level of steam power because they give you finer control for easing the steam on and off.
That control is an essential factor because, with the 1.8-litre steam boiler and the ability to crank up the temperature using the PID, you can get a lot of steam power from the Alex Duetto. It comes with a two-hole steam tip installed, but unlike many manufacturers, Izzo also includes a set of three other steam tips you can swap in two four-hole tips in different configurations and a three-hole tip.
If you’re new to prosumer espresso machines, I’d recommend starting with the two-hole trip. It will steam a bit slower than the other options, giving you more time to master your technique.
Build Quality – 4/5
The build quality of the Izzo Alex Duetto IV is exceptional. You need to look no further than its massive 32-kg weight to understand how many quality stainless steel components it includes, including the frame, exterior, and drip tray.
One of the best features is that the back and sides of the Izzo Alex Duetto are double walled.
Such an insulation strategy is often overlooked by other manufacturers. This avoids adding a lot of ambient heat to your kitchen, a serious consideration on a hot summer’s day when you have a 32 kilo piece of steel heating to steam temperature.
Another area in which some other thoughtful design decisions have been made is the noise level of the Izzo Alex Duetto. Most of the noise in an espresso maker comes from the pump and the motor. In this one, the motor mounts have been reconfigured to dampen vibrations. And the already quiet rotary pump of the previous version has been upgraded to an even quieter model. On top of that, the large removable drip tray has been affixed with magnets so that it doesn’t rattle when the machine is in use.
Another clever upgrade is that Izzo has opted to reinforce the front panel of the Alex Duetto. As already mentioned, the group weighs an impressive 3.6 kilos. While this is great for temperature stability, it can cause the front panel to flex as the portafilter is twisted in and out, a disturbing experience for the user. But not anymore! With additional bracing inside, the Izzo Alex Duetto stands firm.
This is a big espresso machine. The Alex Duetto measures 43 cm tall by 36 cm wide by 43 cm deep. It’s on par with or a bit smaller than other prosumer double boilers, but it will still have an impactful presence in your kitchen. Luckily, with its beautiful sleek lines and mirror finish stainless steel exterior, that impact is positive.
The Izzo Alex Duetto comes with two professional-grade 58 mm diameter chrome-plated brass portafilters, a single spout, and a double spout, as well as appropriately sized steel filter baskets for each. Impressively, it also comes with a lovely metal tamper, easily a hundred pounds worth of added value.
Cleaning and Maintenance – 4/5
If you’ve owned an E61 espresso maker before, or you’ve done your research, you know they require regular maintenance and care. The Izzo Alex Duetto IV is no different. You will need to perform the tasks recommended by the manufacturer, including regularly backflushing and lubricating the gaskets (5).
Any more extensive maintenance is best avoided, which is easily done through proper use and treatment of your Alex Duetto espresso machine. This includes:
- Always use filtered water in the water tank to avoid scale build-up, as descaling a prosumer espresso machine is no easy task.
- Wipe everything down after use with a microfiber cloth, including the shower screen and outer case. Clean the portafilter thoroughly each day.
- Purge the steam wand before and after each use, and wipe any milk off the outside immediately after steaming.
Fortunately, if you need to perform work on your Izzo Alex Duetto, the company has made a few updates to make it as easy as possible. The boiler drains are easily accessible, making the option to drain the boilers easy if you have to descale or need to ship it for service. Both boilers and their heating element are well-mounted so they won’t budge during transit, and rubber insulating boots protect vital joints.
Cleverly, Izzo has opted to invert the motor’s position in the Alex Duetto to move it above the pump. This way, if the pump fails, it won’t also destroy the motor.
Do Not Buy the Izzo Alex Duetto IV If…
You’re not into specialty coffee – If you prefer to pull shots with the same reliable espresso blend day after day, there’s really no need to spend the extra cash on a dual boiler espresso machine with PID like the Izzo Alex Duetto. Instead, look into a high-end heat exchanger espresso machine. For example, the Giotto model from Rocket or the ECM Technika.
You’re buying for a commercial coffee shop – The Izzo Alex Duetto may be prosumer grade, but it’s not rated for commercial use. If you’re buying for a cafe, small or large, check out our favourite La Cimbali machines. Or if you have a bigger budget, take a look at the stunning Kees van der Westen machines (6).
You don’t make a lot of milk drinks – Lattes and cappuccinos not your thing? Then don’t waste money on the Alex Duetto dual boiler espresso machine or even a heat exchanger. Get a high-end single boiler espresso machine instead. Izzo makes a single boiler version, the Izzo Alex, or consider the much-raved-about ECM Classika.
If you’re in the market for a workhouse dual boiler espresso machine from a brand that doesn’t get the attention it deserves, you’ll be thrilled with the Izzo Alex Duetto espresso machine. It doesn’t have quite the flash of a Rocket or a La Marzocco, but it is packed full of key features, looks beautiful, and falls well under the price point of these trendier brands.
- Fekete, M. (2019, February). How brew water temperature affects espresso extraction. Retrieved from https://www.beanscenemag.com.au/brew-water-temperature-effect-espresso-extraction/
- Accuserv Heating and Air Conditioning. (2019, November 29). Heat Exchangers: Copper vs. Stainless Steel. Retrieved from https://accuservheating.com/blog/heat-exchangers-copper-vs-stainless-steel/
- Burton, G. (2011, January 11). The E61 Group Head: An Oldie but a Goodie. Retrieved from https://fivesenses.com.au/blogs/news/the-e61-group-head-an-oldie-but-a-goodie/
- Joseph, H. (2019, December 10). Longtime Espresso Pro Michael Teahan on Pre-Infusion, the Problem with SO, and Much More. Retrieved from https://dailycoffeenews.com/2019/12/10/longtime-espresso-pro-michael-teahan-on-pre-infusion-the-problem-with-so-and-much-more/
- Erasmus, D. (2015, September 28). Espresso Machine Maintenance: The Essentials. Retrieved from https://perfectdailygrind.com/2015/09/espresso-machine-maintenance-the-essentials/
- Hof, K. (2016, February 22). Kees van der Westen: The Sprudge Interview. Retrieved from https://sprudge.com/kees-van-der-westen-93613.html