So much speculation, I had better do my review quickly

Bluenoser wrote:Does the meter on the production model give the steam pressure?.. this will tell what type of steam you get at the various settings.. I might guess it might be about 1bar at low, 1.2 at med and 1.4 at high.. just a guess. But depending on the size of the boiler and the heater, will be interesting to see how much it drops as it steams. (2 hole tip?). One very slight advantage of the PID HX is that you can turn the PID up to get 1.4bar steam if you are willing to flush to cool the TS. But I think from a user perspective, the MaraX has the right philosophy.

here are some interesting vids on this http://www.youtube.com/watch?v=3nCd70QvJcc

Stanic wrote:here are some interesting vids on this http://www.youtube.com/watch?v=3nCd70QvJcc

A lot to take in here.. .. good video.. but almost wants me to ask more questions...

Somehow this guy seems to have thermocouples in about 3-4 places inside his machine. There seem to be 2 sensors in the steam boiler loop and one in the TS.

So not quite sure why you need to flush a bit to get the steam pressure up from 0.5bar to over 1 bar.. But that little flush caused the heater to come on and it then stayed above 1.2 bar when steaming..This would be very important info for a user to know. So this is more steam pressure than my 2L HX which is using a 4-hole tip; but it heats much more slowly.. 45 seconds here.. I can do that 6 oz in about 20 s, but at .75 bar. I'm not sure how many holes are in the MaraX tip.. It appears to heat somewhat slowly.

Also, the temperature at the thermometer won't be what the coffee sees. There is some drop. In my HX there is a 3-5F drop from the thermometer to the coffee when I used a SCACE. So while he shows 93.5C (200F), the puck will see less. (this can only be verified with a SCACE), but I'm guessing maybe 91.5C (197F)? Don't think that thermometer will give you exactly what the coffee sees.

The tablet shows lots of numbers, but really .. a user won't have that to know what is going on. I would rather have a SCACE (no group thermometer) for validating their ranges and then use the steam pressure gauge for the boiler to see what is going on with steam pressure

I think that one would also need to test a bunch of machines to see if results from one machine to another are repeatable and to what level they correspond to really see the success of the design. I'm a little suspicious of if very small differences in TS geometry will lead to different performances. (for instance pipes being a little longer, or having slightly different radius bends)

Seems like a lot of work to control the HX process. I almost wonder if it would not be better spent adding a small boiler above a new group and then controlling that. Yes a DB, but the LM uses a tiny brew boiler.

Potentially, this machine might be more user friendly than a typical HX. Set to low/med/high and pull a shot.And I can see this as being a good choice for someone who wants to make good espresso, but doesn't want to get too involved in the process (and wants a cheaper machine than a DB). But WLL showed stunning vids of their Profitec Pro500HX and my identical model does not imitate theirs in performance. (hence my concern on model variance) This video is pretty interesting, but there could be more performance testing to show how it will respond in rebound of multiple drinks, how it performs from one machine to another, and quality of milk foam.

How did the mara X compare to the Crem One DB for stability?

Thanks.

obviously I don't have the machine but from what I was able to gather:

Bluenoser wrote:A lot to take in here.. .. good video.. but almost wants me to ask more questions...

Somehow this guy seems to have thermocouples in about 3-4 places inside his machine. There seem to be 2 sensors in the steam boiler loop and one in the TS.

there are two sensors, what you can see on his screen are actual vs. set temperatures for those two

Bluenoser wrote:So not quite sure why you need to flush a bit to get the steam pressure up from 0.5bar to over 1 bar.. But that little flush caused the heater to come on and it then stayed above 1.2 bar when steaming..This would be very important info for a user to know. So this is more steam pressure than my 2L HX which is using a 4-hole tip; but it heats much more slowly.. 45 seconds here.. I can do that 6 oz in about 20 s, but at .75 bar. I'm not sure how many holes are in the MaraX tip.. It appears to heat somewhat slowly.

there are two holes in the tip
apparently, in the coffee priority, the temp. of the Hx is set to give around 90-93 °C in the GH, meaning the pressure will be low in the main boiler, you need to "wake-up" the heater by flushing or similar, this causes rise of temp and pressure, without big effect on brew temp due to temp inertia of the system

Bluenoser wrote:Also, the temperature at the thermometer won't be what the coffee sees. There is some drop. In my HX there is a 3-5F drop from the thermometer to the coffee when I used a SCACE. So while he shows 93.5C (200F), the puck will see less. (this can only be verified with a SCACE), but I'm guessing maybe 91.5C (197F)? Don't think that thermometer will give you exactly what the coffee sees.

The tablet shows lots of numbers, but really .. a user won't have that to know what is going on. I would rather have a SCACE (no group thermometer) for validating their ranges and then use the steam pressure gauge for the boiler to see what is going on with steam pressure

I think that one would also need to test a bunch of machines to see if results from one machine to another are repeatable and to what level they correspond to really see the success of the design. I'm a little suspicious of if very small differences in TS geometry will lead to different performances. (for instance pipes being a little longer, or having slightly different radius bends)

agreed, let's wait for reviews

Stanic wrote:obviously I don't have the machine but from what I was able to gather:

there are two sensors, what you can see on his screen are actual vs. set temperatures for those two


there are two holes in the tip
apparently, in the coffee priority, the temp. of the Hx is set to give around 90-93 °C in the GH, meaning the pressure will be low in the main boiler, you need to "wake-up" the heater by flushing or similar, this causes rise of temp and pressure, without big effect on brew temp due to temp inertia of the system


agreed, let's wait for reviews

So let me get this straight. The pressure in the boiler is at first low in order to get the proper hx temperature water. Pour your espresso. Next you wake up the machine with a quick mini flush to increase the pressure in order to properly get good amount of steam. Steam your milk.
Now you want to make another cappachino so what is next? You have full pressure boiler that needs to go back to lower pressure in order to get the proper espresso temperature
Cooling flush?
Wait for it to go lower on it's own?


Any comments welcome


Randy

Making coffee would most likely be enough to "wake up" the boiler
According to the video the heating goes on for one minute, so probably it will not overheat too much, idk

Thanks for the review Jim! Boy am I glad I pre-orded the MaraX

where did you preorder if you don't mind?