Vibiemme Domobar Super Lever Review
by Randy Glass - Copyright 2008 - All rights reserved
E-mail me at email@example.com
Vibiemme Domobar Super Lever Review
I have been mentally laboring over this article for many months now, having started it three different times only to become frustrated as to what direction it should take. I humbly call this a review. I am not really qualified to write a "real review" of this machine because of my limited experience with the upper-end home machines now available. Limited is certainly an understatement since this is the only heat exchanger machine I have ever owned, or even used for that matter. On Home Barista.com there is an excellent review/thread done by experienced and knowledgeable users. Also available is the full, edited review on Home Barista. Dave and Dan put this machine through its paces in a manner that would make any scientific effort on my part pale in comparison, and at best be just a redundant, second-rate attempt to try to document the machine.
Six and one half years can be a long time (or not). In the world of espresso, if you haven't 'milked' (sorry) all you can from your espresso machine in that amount of time it is probably either well past time to get some help or time to switch to tea... Of course, there really is no "perfecting" a technique or process with any given espresso machine- there is always a plateau that is unreachable think "Sisyphus" and you are getting close to the idea. If we are forced to apply a sports analogy it would be golf. A perfect score is 18 and no one has ever gotten even remotely close to that. The greatest and most notable difference between playing golf and making espresso is that I have never wanted to throw my espresso machine into a lake. No matter how good that last espresso was, the goal is to make the next better, or at least as good as you remember. That unreachable goal is probably a good part of the infection that hits us all. It can be resisted for some amount of time, but the odds of it infecting you are directly proportionate (or even logarithmic) to the length of time you have used any given machine.
I had been thinking about upgrading for some time now. Without a doubt, Silvia has served me very well for the 77 months I had used her, but there are certainly some little annoyances that dog the user of just about any single boiler machine. Mainly, being forced to do the "brew-steam-brew dance" when making milk-based drinks— make espresso, turn on steam switch, wait, bleed water from wand, wait, and then try to hit the steam at the peak of its range before the thermostat clicks off. Then finish steaming milk, turn off the steam function, bleed off the steam while refilling the boiler, and then wait some more for brew temperatures to return to normal before pulling another shot. With small home machines you also deal with a relatively small drip tray and the wide temperature swings caused by button thermostats (cured by PID installation for the most part). And then there is the matter of no warning in some machines that the reservoir is running low and no way to see the level of water in the tank other than to lift the lid and peer into the tank (a universal problem with some machines which are not plumbed). With Silvia there was also the annoying effect of lifting the tight-fitting reservoir lid which sucks in any stray dust or coffee particles left on top of the machine around the reservoir.
So the next step in machines is explored, and if you think it is difficult deciding on a machine selling in the $300 to $600 range, try to choose a machine in the $750 to $2000 range. Like buying a car, each step offers slightly better options included as standard equipment. As you move up the ladder (or, from the viewpoint of the bank account, down into a hole) the boilers get larger, brewhead design changes, electronic controls become more advanced, more stainless steel, and other such benefits. In some cases the benefits are not obvious, comprising research and design that only shows in the cup. The machine I stepped up to is the Vibiemme Domobar Super manual.
The Vibiemme Domobar Super Lever Operated E-61
What's that Sitting Behind the Vibiemme? That's NOT Rocky! Details in a week or two.
There is no story as to how I chose the Vibiemme because the Vibiemme Domobar Super chose me. I was hired to write an owner's manual and user's guide by a reseller and so a deal was struck and I now have a Vibiemme espresso machine. My machine came to me from Jim at 1st-line.
When Faema was taken over by the Italian government for financial difficulties, three executives went off to form Vibiemme. The company name came from the names of the executives who left Faema and formed the company: Valente, Biancolini, and Meroni. (V, B, and M). It is pronounced like the letters of the Italian alphabet: Vee—Bee—Em-may. The E-61 brewhead was invented in 1961, a year that featured a solar Eclipse, thus the name: E for eclipse and 61 for the year. Besides years of experience, they brought with them the patent for the famous E-61 brewhead which they still hold. All other E-61 brewheads are made under license from them.
The Domobar Super line comprises Vibiemme's upper-end line of machines designed for home use. Indeed, Domobar means "Home Bar" in English, and the "Super" designates these as their premium home machines. At the time I received my machine the Super line was made up of three models, each available in stainless or black exteriors. The three models are basically the same internally with a different user interface/control systems:
My parcel arrived on May 31, 2007. To call it a parcel does not do the machine nor the UPS delivery person justice. The shipping weight in right at 70 pounds! I used my hand truck to get the machine from the garage to the den where the Vibiemme would live.
At $1500, most non-espresso folks would think it insane to spend that much on a coffee maker, but in perspective not doing so doesn't make much sense. After all, plenty of people don't give a second thought about a $3000 plasma TV, a $1500 surround sound system, a $2000 washer-dryer set, or a $1200 refrigerator. And yet many of those same people don't give a second thought about making their morning coffee on a $22.00 Misses Kawfee and wonder why anyone would spend $110 on a Bunn, or possibly even more on a quality Grind 'n Brew combo machine. Everything is relative, and we all set our priorities and move on.
Some noteworthy features of the Vibiemme Domobar Super that make it stand out:
The Vibiemme E-61 brewgroup is as massive and beautiful as it is difficult to photograph. Think "Hall of Mirrors" and you begin to see the problem!
Not to worry— I was fully dressed when I took this photo.
Included with the machine at the time of this writing are separate single and double spout portafilters as well as single and double baskets, a brewhead brush, a coffee scoop, a plastic tamper that is as useful as the one that comes with Silvia (which means that it is totally useless), and a blind filter basket for backflushing. As with all machines that have a 3-way valve (whether mechanical or electrical), the Domobar should be backflushed on a regular basis to help keep the brewing path clean. You also get the printed, factory manual and, through at least two of the domestic suppliers, you will also get a highly-detailed and illustrated owner's manual, more than 40 pages in length, supplied in PDF format on CD (check with your reseller before ordering, particularly if this is your first HX machine).
At 10.5" wide, 15.375" tall, and 20" deep, it is best to measure your space before ordering. The water reservoir is located at the back of the machine. The cup warming tray needs to be removed to access the reservoir, so if you intend to place the machine under a cabinet, verify that you have room above to fill the reservoir. At 70 pounds, this thing is not a machine that is going to be happy being slid around on a counter top.
The VBM, like most all commercial machines in use today, is a heat exchanger design. There is a large boiler that holds hot water and steam. Hot water is dispensed from the bottom of the boiler through the hot water wand. Steam is drawn from the top of the boiler for stretching milk. Another pipe passes through the boiler. This tube, the heat exhanger, is partially immersed in the hot water. It is the brew-water path, and the water that passes through this special pipe is completely separated from the boiler water. The brew water sits in this pipe and is heated through conduction from the main boiler- the heat is exchanged from one to the other, hence its name, Heat Exchanger.
Another feature of the E-61 brewgroup is the thermosyphon. A group this massive needs to be heated or else the mass of metal would sap the heat energy out of the brew water and thermal control would be totally lost. To accomplish this, the brew group is connected to the heat exchanger in a loop fashion. The brewhead has two hot water pipes connected to it— while idling, one pipe carries hot water to the group and the other returns the now cooler water back into the heat exchanger. This is all passive (the pump is not operating), being accomplished by convection (heat rises, cold sinks and this creates the flow on its own). This process is quite effective, heating the brewhead in about thirty minutes, and making it too hot to give more than a momentary touch in less than an hour. The metal will be maintained at around 200F. Keep this in mind if you have little ones in the house. Even adult visitors will be drawn to the beauty of the beautiful chrome of the Vibiemme's E-61 grouphead. "No! Hot!"
The thermosyphon is not a unique feature of Vibiemme E-61's grouphead, but they have taken this feature a bit further using large, 12mm (approximately 1/2") diameter copper pipes which flow more water with less heat loss. Round tubing has the lowest surface area to volume of any shape so the larger the tubing the more efficient the thermosyphon can be in transferring heat to the brewhead. Smaller, more compact machines do not have the room to run pipes of such large diameter in their cases.
If you intend to turn on a machine this large and think it will be ready to make coffee in fifteen minutes, you are mistaken. That large boiler and all the water inside it, the large brewhead (as found in all such machines), and all the related plumbing inside takes time to become heated and ready for use. About an hour is recommended, with thirty minutes just to get close if you are desperate for a cup of coffee. These machines are designed to be left on all day. The boiler refills automatically using a small computer box (the Gicar) connected to a water level sensor in the boiler. There is a safety switch that turns off the pump and heating element if the level gets too low, and the boiler is equipped with a resettable safety thermostat to stop operation if the boiler overheats from having a too-low water level.
After you manage getting the thing out of the shipping box and (preferably with assistance!) get it up on the counter, you are nearly done. Final set up is quite simple- screw in the four, large metal feet (they are removed for shipment to protect the machine), wash and then fill the water reservoir, make sure the valves are closed and the power switch is off, and plug it in.
As with any HX machine, the quality of the water is critical. Too much mineral content, particularly in the form of lime or calcium, and rapid build up of hard-water deposits will result which can lead to all sorts of problems including under-filling or over-filling of the boiler, heating element failure, and decreased volume in the boiler. Too little mineral content and the water level sensor will not operate properly and the boiler will surely be over-filled. A Brita filter system can remove most of the harmful mineral content of most water, but the user should get a TDS meter to keep track of the filter's effectiveness. A TDS of around 25 to 50 will work fine, and around 90 to 125 for best taste. With my well water's 200-250 TDS and above at times, I add Brita water to RO water to get the correct hardness. For a more thorough education on water, refer to Jim Schulman's excellent, and aptly named "Insanely Long Water FAQ."
Once the reservoir is filled, turn it on! The feel of the switch is also a reminder of this machine's commercial nature. It has a heavy feel, and the detents are solid and serious as you might expect to find in Dr. Frankenstein's lab... Or is that Fronkensteen?
Note how much room there is around all the components
As you can imagine, it is quite a big jump to go from a single boiler machine with button thermostats (or even PID'd) to a commercial-quality E-61 machine. The basics are all there- grind, dose, tamp, lock, brew. But differences surface immediately. Since the E-61 brewhead has a bit more room for coffee you can dose different amounts, or at least to say that there is a wider range since there is no shower-screen retaining screw to deal with. It's the same with any machine- the sweet spot between too much and too little coffee, and the proper grind and tamp has to be found.
The brewhead design is not just a huge chunk of metal either. It is a well-proven design that changes the way water is delivered to the coffee. When the brew cycle is started there is a piston in the brewhead that is held in place by a strong spring. Until water pressure builds to brewing force this spring and piston assembly and its related parts limit the water flow and pressure reaching the coffee. It is sort of a low-pressure pre-infusion that is automatic. The benefit of this system is that you can actually tamp just a bit lighter because this early, gentle water flow will migrate the fines towards the bottom of the coffee puck and it also gives the coffee a few seconds to swell and settle itself. You can actually see the pressure change on the brewing gage. It settles on about 4 bar for about five to ten seconds before gently ramping up to the brewing pressure.
Speaking of brewing pressure, the Domobar Super machines are equipped with large over-pressure valves. Although there were some early ones (in mid-2007) which were supplied with the wrong spring, this problem was addressed and the pressure is now easily and accurately adjusted by turning the large screw on the pressure valve. To access the adjustment, the outer cover must be removed. The valve is accessed through a cut-out located in the back of the machine's inner divider. Vibiemme choose to not supply access to the valve through the outer case. The correct spring makes the adjustment very linear, like a volume control on a stereo.
Brew temperature is controlled to some extent by the boiler temperature. This is measured and controlled indirectly by using the pressure in the boiler. Applying Boyle's law, if the temperature of a gas in a closed system is increased, the pressure will increase to a computable level. Thus, the pressure of the heated water in the boiler can be accurately used to judge its temperature. This is done by the pressurestat- sort of a pressure-thermostat if you will. The pressure goes up as the water is heated, pushing on a diaphragm which opens a switch, stopping the flow of electricity to the heating element. When the temperature drops the pressure also drops, the diaphragm moves and closes the contacts which energizes the heating element once again.
Although it would seem that this wide swing of pressure would seemingly cause a corresponding fluctuation in brewing temperature, that is not the case. There are a number of buffers in the design of the system that eliminate that. The heat exchanger in the boiler adds to stability as does the massive brewhead. You can read the charts in the review at Home Barista, but once the "pre-infusion" ended, the brew temperature throughout the pull has been shown to hold stead within about a one degree range. Quite amazing when one considers that this machine has no electronics to control temperature. Beyond that, the same review showed that five shots pulled in succession ended at exactly the same temperature, measured to a tenth of a degree. "I doan gots to cho you no stinkin' PID."
The downside of this system is that the E-61 thermosyphon brewhead experiences overheating. While the machine sits idling, heat builds up in the heat exchanger as well as in the brewhead. it depends on on the setting of the pressurestat, but I have seen temperatures in excess of 210F. of brew water in the grouphead. This has to be mitigated before pulling a shot of espresso. To do so, the user needs to do a cooling flush.
Before preparing the shot simply remove the portafilter and start a brew cycle. How long to allow water to flow into the drip tray becomes the question. Some users just measure a volume of water. Others wait for steam in the flow to cease and then count a number of seconds. The best solution is to use a thermometer. Eric S. (firstname.lastname@example.org) has developed an adapter that is installed in place of the hex-head socket screw on the front of the brewhead. This allows the use of a digital thermometer or thermocouple to measure the water temperature just before it enters goes through the shower screen. Using this data to flush to the same temperature each time just about guarantees consistency. Do a search on Home Barista.com for "Eric S." for more details on this excellent device.
The biggest question to be answered is, how does it compare. After nearly seven years with Silvia, my leap from a small single boiler to a huge HX machine was a big one. These machines are in two different worlds. The Domobar Super's brewhead alone weighs nearly a third of Silvia's total weight! Specifications are merely a starting point. The only dependable way to judge a machine is to use it yourself and taste the coffee.
In use, a heat exchanger machine with such a relatively large boiler offers a lot of thermal stability and reserve energy, and makes it a lot easier to use right out of the box. The Vibiemme's 2.7 liter boiler vs. Silvia's .36 liters gives the Vibiemme a 750% more capacity. So what? Let's remember that a portion of the Vibiemme's boiler is filled with hot water and the rest is steam. That steam exists all the time once the machine comes up to temperature after being powered up. No more switch flipping and watching lights. You can steam any time you want- just open the tap and steam flows (after clearing any water that has accumulated, of course). Once you become comfortable you will find it quite natural to steam while pulling shots. For a standard double cappuccino I have found that the powerful steam will stretch the correct amount of milk for two cappuccini in about the same time as it takes to pull the second double.
Small home machines are challenged to pull three doubles in a row. Their relatively small boilers lose thermal stability and the heating elements are just too small to keep up with the challenge. Add steaming to the mix and the small machine falls into the shadows as an also-ran. The Vibiemme Domobar Super will out perform all but the most talented barista. In testing it has been shown that the Domobar Super can not only produce double after double with barely breathing hard, it does so with dramatic stability as well as repeatability that is virtually perfect.
The design of the E-61 brewhead really shines when compared to smaller home machines. With the Silvia you turn on the brew switch and within a second or three the pump is working to deliver the full pressure as governed by the overpressure relief valve mounted on the boiler— basically, the coffee is assaulted. The E-61 design slowly delivers the water up to about 4 bar, and it stays there until pressure builds in the brewhead and head space above the coffee until it is full of water, and only then does the pressure gently ramp up to brew pressure as governed by its over-pressure relief valve.
No machine is perfect (not even my 1990 Volvo 240, which I love.. no cup holders). Most of my complaints about the Domobar Super are small and some even petty, but for this kind of money for a machine that "just" makes coffee, I feel I have the right to be picky. Here is a list of some of my findings:
Vibiemme is not resting their laurels. At around the time of this writing they are about to introduce new models into the States including features like plumbed-in options, rotary pump, and dual boiler models. Hopefully I will have some pictures and more news from the SCAA show in Minneapolis in early May.
It has been about ten months since the Vibiemme Domobar Super arrived here. It did not take long to realize that this machine was well designed and produced. From the first shots after I dialed in Rocky, the espresso has been very good. I have had far fewer bad shots in all those ten months than I had with Silvia in any given two or three week's time. Excluding a very few sink shots, the worst shots over the last ten months from the Vibiemme have been on par with most of the good to better shots I got from Silvia.
So a HX machine is faster, more consistent, and more flexible in use. So why are machines in the "entry level" of around $250 to $500 called entry level or beginners machines when they are more difficult to use and deliver only marginal results when used as intended? If you frequent the various message and discussion websites, try convincing someone that they should spend $1500 on their first espresso machine. It wouldn't have worked on me in late 2000!
On the other hand there is a lot to learn with a machine that forces the user to "work it" to get it to operate within the parameters needed for quality espresso. But if that were a universal truth, everyone would start out pounding their clothes on a rock at a river's edge before buying their first washing machine.
You will hear discussion about how the E-61 grouphead is an old design that has been around for ages (about 47 years to be exact). How could any espresso machine design last that long? Why is it still being produced? Anyone..? Because it works! The drawback of overheating is not only easily dealt with but is far outweighed by the gentle delivery of water to the coffee and thermal stability.
I was a bit reticent before receiving the Vibiemme. There are a lot of quality espresso machines in the $1400 to $2000 range. It was a relief when one found me instead of me making the decision. For $1500, the Vibiemme Domobar Super manual is an excellent machine and one that, I feel, any home barista would be proud to own and one that would give many happy years of service.