Compak K10 WBC grinder - user report

Grinders are one of the keys to exceptional espresso. Discuss them here.

#1: Post by NoMilkToday »

More than a month ago two glorious events happened upon me. First, I received my new grinder, a big conical (68 mm), the Compak K10 WBC. Shortly after that, my trusted dealer (Van Pommeren in Utrecht) gave me a La Marzocco single basket. Using the K10 made me a very satisfied man; therefore I decided to share with you my positive experiences in this post.

For five years I have been a satisfied Mazzer Mini owner. I had no idea that a better grind quality was even possible. That was until I read the well known threads "the Titan Grinder Project" and "Can it beat the Robur" on Then I realized that the taste of my espresso's could be further improved. But how to choose the right grinder?
Reading and rereading these threads and interpreting plusses and minuses of the tested grinders and comparing the findings with my own requirements, I unfortunately found no clear winner, a grinder that stood out and was unique by having all the qualities I looked for. I hate compromises; I want it all: excellent grind quality, reliable, good service (that never should be needed), neat, no clumping, easy to clean, but also smaller than 60 cm.
Unfortunately, there is no place in my country where I could A-B test high-end grinders of various manufacturers.

Therefore I visited several shops, even a distributor and also several fellow espresso addicts in order to slowly learn more about the subject of top grinders. After tasting espresso's from a lot of different combinations of espresso machines, grinders and espresso blends I unexpectedly found the espresso machine that I wanted (but not searched for) and later bought (the Izzo Alex Duetto). But a grinder? No, they were all different and none made a lasting impression. The doserless ones clumped, some of the dosered ones were messy and none of them had that sweet and pleasant taste I read about in the above mentioned threads. On the contrary, some of the big commercial grinders did not even taste better than my Mini.
So I further studied the subject by reading the relevant posts on all espresso websites and blogs I could find with Google. After some time, I noticed that there were three grinders from my original shortlist that were regularly mentioned by satisfied users: the Mazzer Robur, the Anfim Super Caimano and the Compak K10 WBC. All very different; all with their own set of plus and minus points.
Because I wanted more specific information about hopper alternatives and modification possibilities (Anfim SC: how about making a stepless version and when will there be a conical version, Mazzer Robur: how to remove the auto fill, does the Mini hopper fit and so on), I shot emails to various manufacturers. The only one that answered my email was Compak (even within a day!).

I already read on the various websites that Compak was more customer oriented than others by acting fast on user complaints and offering incremental improvements of the K10 WBC (the plastic fork was replaced with a metal one, the unreliable on/off switch with a sturdy circular one, the integrated doserlid with an easily to remove one - just like the Mini, offering different size hoppers and so on). Their commitment by sponsoring the World Barista Championship and letting the competing barista's use their K10 was a positive factor that confirmed my confidence in this brand.
So I had a good feeling about Compak. Also noticeable was the competitive price. The K10 WBC is far less expensive than the Robur and even less expensive as some medium conicals like the Kony and the MXK. Further, in the mentioned threads I read that these medium class conicals (62 mm) all had a rather bright taste profile, a quality I despise.
Hence I made my dealer happy and ordered a K10 WBC. The dealer gave me the option to choose between three hoppers: the standard one (1,7 kg), the one of the K3 (900 grams) or the short mini (275 grams). I choose the last one, giving my grinder, including hopper, a total height of 48,5 cm. That is so neat, a big conical in a short package. Price paid was Euro 1129,=

Things I do not like
What I do not like in big conicals is their big, difficult to clean chute. Before every session you have to clean the chute to prevent stale grounds mixing in with your fresh ones (about 5 grams in the K10's chute). Cleaning the chute is hindered by a plastic box sitting above the chute. With most big conicals this is the auto fill "feature". With the K10 WBC it is called a "hand protector". Upon questioned, Compak gave me explicit instructions on how to remove the hand protector (and warned me that this hand protector has a function: protecting my safety). Great, thanks for the warning and the removal instruction, problem solved.
Although I prefer dosers because of their more clumpless grounds, most of them leave grounds after the dosing. This is hardly neat. Happily, on the internet there are instructions to be found on improving this. For example on ; see the page "Sweep mod for the K10". By the way, the proprietor of this informative and fine looking website seems to be a nice fellow, sharing his espresso experiences with us in an open and honest way. This is not the typical proud owner defending his buying choices against imagined attacks from others. Therefore I was sorry for him to read that he had to sell his K10 because his better half found the K10 to be too big to deserve a place in the kitchen. Am I naive in thinking that the K10 just looked beautiful standing besides that GS/3? By the way, this is the old model K10 WBC you can see, the one with the integrated doserlid. Unfortunately for him, he downgraded to a Mahlkönig K30. Several times I tasted espresso's ground with a K30 and a K60 (twin hopper); every time I found the taste harsh and bright. If this guy knew then about the three different hopper options Compak offered, he possibly would have bought the short one and had met less female resistance with his K10. Poor guy.

In use
You will not overlook the K10. With the short hopper it looks like a military robot from Star Wars. Short, fat and black. And heavy. And very functional. Its manufacturing quality looks outstanding to me. I think it could outlive me.
Normally I buy espresso beans in kilo packs. After opening a kilo pack, I divide the beans over eight glass jars and the hopper. I place special lids over the jars and suck them vacuum with my little Solis machine. The idea behind this operating procedure is to start each session with relatively fresh beans. Therefore I like the small 275 gram hopper. On average I use between 80 and 120 grams per session.
Working the K10 is a pleasure. With its big motor (760 W) and low RPM (300) the high pitched sawing sound of the Mini was replaced with a pleasantly low sounding roar; like cruising in a V8-equipped saloon. Further, grinder speed is high. Filling the LM single basket takes about three seconds (Mini 14 seconds). It could be me, it could be the K10, but on sight I can grind the exact right portions. No timer is needed.

Taste profile
The first coffee I put in the hopper was the freshly roasted single origin "Big Mexican" by a nearby Dutch roaster named Golden Coffee Box. The name is referring to abnormally large beans. Before I had the Duetto, I never liked single origins. Their taste was sour and too simple for me, lacking the sweet complexity I like so much with the better mid-Italian blends. Because of the Duetto's PID-controlled temperature adjustment possibilities I learned that a lot of the single origins need a higher temperature than a HX-machine standard can provide. This one needs 98°C (offset is 10°C). With the Duetto/Mini combination the "Big Mexican" turned out to be an average nice espresso. With the K10 the taste became much softer, sweeter and new taste layers were revealed, just like a good blend. I was positively surprised. The improvement in taste, mouth feel and after taste was beyond my expectations.
After a week I put Pont Si Senor in the hopper. With the Mini this Spanish blend tasted soft, sweet and a bit sandy, muddy even. Taste layers seemed to flow into each other as one thick muted layer. No, not to my liking. With the K10 taste became much more refined. With a temp of 96°C and use of the LM single basket my wife and I proclaimed this the best espresso we ever tasted. This was like a very, very good Italian blend, exquisitely sophisticated, very different layers and at the same time soft and sweet. What an incredible difference! What a great grinder this K10 seems to be.
And then came the coupe de grace. One of my two favorite blends is Miscela Romcaffè (the other one is Caffè Martella Maximum Class). With a Romcaffè filled portafilter in the group I watched the single spout and saw a very slowly, globby substance bubbling out. It looked like pure and very dense crema. And it kept coming; even after 40 seconds there was no sign of blonding to be seen. Totally amazed I inspected the cup and swallowed the content in one sip. Wow, out of this world. Words like soft, sweet, creamy, rich, foamy, airy, complex, refined seem like a cliche and do not describe my feeling. Interestingly, some of the taste layers had speckles of sweet bitterness. Very nice. Normally I despise bitterness or sourness, dialing in the Duetto just in between. But when harsh bitterness turns into sweet bitterness? I love it. After lowering the temp to 95°C the sweet bitterness disappeared and was replaced with even more intense taste layers; taste aspects like chocolate, caramel and nuts were further deepened. Well, until now I find the combination of Romcaffè, K10, LM single basket and Duetto impossible to describe. The ristretto this combination produces is beyond my most fantastic espresso dreams. A complete new sort of beverage.

Upgrading my VBM Super to a Duetto resulted in improving the quality and especially the consistency of my espresso's in a big way. However, the upgrade of my Mazzer Mini to the K10 turned out to be an even bigger step up in quality, much bigger. Every espresso and ristretto I make is soft, sweet, rich, creamy and clear at the same time. Use of the LM single basket further intensified these qualities, while also making the espresso preparing process less finicky than with even the standard Izzo double basket.
At this moment in time I'm fully satisfied. Finally, after a long search, I think that I have reached my goal: preparing the perfect ristretto, each time I want it, in a simple process without magic tweaks or tricks. I just grind some beans in the single basket, followed with a light tamp with my convex tamper, shoving the portafilter in the group, engaging the pump and, after about 30 seconds, I stare in the cup, seeing a globby, bubbly and liquid gold colored creamy substance, knowing on beforehand that it will taste heavenly with an ultra foamy mouth feel and a long, very pleasant aftertaste. I'm so happy.
It has been written on the internet, time and time again, that the influence of the grinder on the end result is even more important than the espresso machine. Experiencing that for yourself is something different. Now I know this is true. Summarizing my experience in a mathematical formula leads to this equation "Fresh roast + Duetto + K10 + LM sb = Heaven". Espresso heaven, that is.

Regards. Wilco

User avatar

#2: Post by edwa »

Would you share a picture of your short hopper K10?

NoMilkToday (original poster)

#3: Post by NoMilkToday (original poster) »

Shure. But do not expect anything fancy. I am a minimalist at heart in not even having a mobile phone. My wife made this photo with her old and cheap digital camera.

Regards. Wilco

Ken Fox

#4: Post by Ken Fox »

The picture is more than sufficient to show you have found an aesthetically pleasing hopper for this grinder for use in a domestic kitchen.

Could you tell us a little more about this hopper? I doubt it was made for the Compak specifically. Is it the "mini" hopper made for a Mazzer model or some other brand, that might be available to us for purchase in another location than the Netherlands?

Thanks in advance,

What, me worry?

Alfred E. Neuman, 1955

User avatar

#5: Post by Sebastiaan007 »

This hopper is made by Compak for all their grinders.
All the grinders have the same entry size for the hopper.
There are 3 sizes, 275 gr. / 800 gr. / 1700 gr.

You can order them by Compak if you are a dealer.
I barista, do you?

NoMilkToday (original poster)

#6: Post by NoMilkToday (original poster) »


I have you and Jim Schulman to thank for your work in the "Titan Grinder Project" and "Can it beat the Robur" threads. You two are responsible for putting me on the right track in choosing this fantastic big conical.
And the K10 with the short hopper is indeed a beauty. In the hopper there is a hollow plastic lid mounted to prevent the springing of beans. It seems to work.

Regards. Wilco

User avatar

#7: Post by shadowfax »

Thanks for the write-up, Wilco. It's really nice to read more about this grinder. It looks really, really sharp next to Alex on your bar.
Nicholas Lundgaard

User avatar
Supporter ♡

#8: Post by GC7 »

Sebastiaan007 wrote:This hopper is made by Compak for all their grinders.
All the grinders have the same entry size for the hopper.
There are 3 sizes, 275 gr. / 800 gr. / 1700 gr.

You can order them by Compak if you are a dealer.
That looks exactly like the hopper on my Compak K3 touch. It's really convenient to get on and off and my vacuum attachment fits perfectly into the chamber of the grinder for cleaning. If there were a complaint about the hopper it is the lid/cover which is a bit flimsy and does not fit easily on top. I use the little sliding lid inside the lower part of the hopper to hold beans back from the chamber if I need to make an adjustment to the grind. When adjusted I just pull out the lid and grind away as the beans fall into the chamber. It's also good for small single doses to limit popcorning.

Nice setup though. Enjoy and thanks for the review.

User avatar
Team HB

#9: Post by another_jim »

I'm glad you liked it.

The 68mm conical is an espresso grinder category, with lots of models available (I know of 6, the three I tested plus Cimbali/DRM, Rossi, and Eureka). There is no mystery why this is the case; the grind quality is superb and ultra-consistent, and the burr set seems to be easily available to any grinder manufacturer.

I liked the Compak best of the ones I tested, since it had a slightly better motor than its rivals. It's good to hear that they've improved the flimsy on/off switch as well. Sadly, their US importer is currently not making this model available at even a remotely reasonable price, the US MSRP is about 60% higher than in the rest of the world. So I suspect that other commercial conicals grinders will be the norm in the US market.

Quite frankly, I don't understand how espresso manufacturers regularly end up destroying themselves like this here in the US. Cimbali and Reneka are two more examples -- they own large chunks of the market everywhere on the planet except the US, where they are not a factor, since their importers add medieval level markups.
Jim Schulman

User avatar

#10: Post by HB »

NoMilkToday wrote:<snip>

To EdWa: 1 inch = 2.54 cm. When I calculate this accurately, my outcome of the total height of the K10, including the 275 grams hopper, is 19 inch, not 21. And if this does not fit, then you seem to have extremely low hanging cabinets. Perhaps you could place the grinder on a side table?
Further you ask "Do the ones in the US have the more reliable on/off switch?" I presume the answer is "yes" but I am not shure. You could check with Chris Nachtrieb. And should you do this, then you can also check the real price to pay for a K10 and report this back to us. If Jim is correct, this could be (depending on your negotiating power) under $1k. And if that is true, man, than the K10 really is the deal of the century, so to speak. I hardly can believe that.

All this talking about prices can distract attention away from the real topic, the very significant increase in quality of your espresso by using a big conical like the K10. And perhaps a bit buried in my report: the La Marzocco single basket is truly wonderful! In comparison with other single and double baskets this thing results in a much better look, mouth feel AND taste. And to top it off, it is far less sensitive to little errors in dosing, distributing and tamping. Disclaimer: a convex tamper gave me better results than a flat one. For 15 bucks this a no-brainer. Buy it or ask Santa.
Subsequent follow-on discussion split to MAP and MSRP practices of online resellers...
Dan Kehn