Isn't it the vacuum created by the condensing water vapor, rather than gravity, that pulls the coffee down through the filter?

How cool! I'm excited to go get one of these. Thanks for the info Mat!

Everything old is new again :-) This general design was pretty popular at one point (maybe in the early sixties?) I've gotten both electric and stovetop stainless steel versions off eBay. I find even the electric one a bit too much overhead with respect to cleaning to use on a day-to-day basis but it does make good coffee.

Check out the aeropress as well - seems easier and makes a great cup of coffee.

A 'vac pot' operates identically to the age-old 'moka', the steel stovetop espresso/coffee maker.

http://en.wikipedia.org/wiki/Moka_pot

Cheap mokas (in the $2-5 range) tend to stop working due to cheap materials, but an 'expensive' one at $10-20 will last years.

We've used a Bodum Santos coffee maker for years. It's an electric version of the same vacuum process so you don't have to worry about breaking glass and you don't have to stand and monitor the process.

I grind the beans and turn it on first thing in the morning and then I am free to get the fam up and out of the house. It makes the best coffee.

Two comments (actually a comment and a question):

(1) I don't think this is exactly the same thing as a Moka pot - the coffee grounds in a moka don't move, and the coffee (liquid) moves in only one direction (upwards), not two (up, then down). Whether this really make much difference is another question, but (finally) the cloth filter would filter very differently than the metal filter in a moka pot. I have several moka pots and only use them when my espresso machine is on the blink. I don't really like the coffee they make, and can't recommend them (but to each his own, of course).

(2) Can anyone confirm whether the "Bodum Santos Stovetop Glass Vacuum 34-Ounce Coffee Maker" is roughly the same thing as the Yama described here (apart from the different volume)? (This does not appear to be the same bodum mentioned by #3 - this is a stove-top like the yama).
Both are available through amazon.com, but only the Bodum is available through amazon.de - which is important for me, since I live in Germany. Probably there are other sources for the Yama here in Germany, but the two machines look very similar - but somehow not quite identical. Do any of you who have used these machines see any improtant differences here?

My mom had one of these when I was growing up in the 50's. It fascinated me endlessly watching the water rise up into the top bowl and gradually filter back as brown liquid to the bottom bowl. I haven't seen one in years, I guess someone decided to revive the technology.

Vacuum coffee is easily the best way to brew your coffee. Try one and you will throw the electric drop pot out in the street. If you don't always have time to use the vacuum get yourself a Chemex manual drip pot. It will make even grocery store coffee drinkable.

As it cools, the coffee is siphoned back down into the bottom through a cloth filter, which helps extract most of the moisture and flavor from the grinds via gravity

A minor quibble, but the water is drawn back to the lower chamber not by gravity, but by the vacuum created when the contents of the lower chamber boil into the upper chamber.

I had a Bodum Santos coffee maker for two years and while I adore vacuum press coffee, I found the electronics of that particular unit unreliable; after sending it back for warranty service nine months after purchase because the programming failed completely, a year later it developed the distressing tendency to reboil the coffee after the steeping cycle. I've had to retire the Santos and have gone back to French press, but the Yama looks like a nice little stovetop unit.

This brewpot is my new bicycle.

The original glass vacuum coffee makers are from the British Cona company
http://www.cona.co.uk
Apparently they first made them in 1910 and still make them now. They were really popular in the UK in the 1970's
Shame their website isn't as good as their products

I think vacuum pots are not quite the same as a Moka pots. Moka pots are (a weak) espresso where the steam percolates through the grinds, a vacuum pot works via water. In a Moka pot, gravity pulls the water back into the lower container whereas it is a vacuum that does the work in a vacuum pot.

I think the advantages of vacuum pots are that they always brews coffee at optimum temperature and that the system contains just glass (and paper). The coffee won’t be as strong as a Moka pot.

I think there's some confusion about the different types of brewing methods and equipment.

Vacuum pots brew coffee using an "immersion" method; the ground coffee steeps in hot water. Other immersion methods include the French press (also called a "press pot"), the Aeropress, the Eva Solo, and the Clover machine. The main technical difference between various immersion methods is how they separate the grounds from the liquid before serving. Vacuum pots, the Aeropress, and the Clover force the coffee through a filter using pressure. French presses use a metal screen on a plunger that is gently pressed down to separate the grounds from the liquid. The Eva Solo uses a filter in a spout, so that the grounds are filtered out as the coffee is poured. The simplest method is cowboy coffee, which mixes coffee and hot water in a pot and lets the coffee settle to the bottom before serving.

Espresso machines and moka pots are pressure methods. They force hot water (not steam, as been said in other comments) through ground coffee. In espresso machines, the ground coffee is tamped down to compress it before the water is forced through it.

Drip coffee uses gravity to pass hot water through ground coffee. Most automatic coffee makers and manual pots like the Chemex use a paper filter to hold the coffee. One variation on the standard drip method is the Vietnamese coffee filter. It's a small metal canister that sits on top of a coffee cup. The ground coffee goes in the bottom of the canister, and is then compressed by a disk that screws down on top of it. When the water is poured into the top of the canister, it seeps down through holes in the disk, though the coffee, and out through holes in the bottom. You control how slowly the water flows through the coffee by tightening or loosing the disk.

Other methods include Turkish coffee, cold-brewing, and percolators.

I've got one of the Cona vac pots--makes good coffee (I still generally prefer americanos from my Salvatore espresso machine) and its set up to use an alcohol burner, so you can take it to the table and get rave comments from your dinner guests. It also uses a glass rod as the filter--no messing around with paper/fabric. Aesthetically, I'd also say it beats out the Yama.

Then again, you could buy four Yamas for the price of the Cona. Wish the Yama had been around when I was shopping...

(And, yes, you need to get a burr grinder. I really like the dosing grinders--think mine is a Pasquini Moka--which is almost necessary for espresso machine users, but I'd see as very handy even for other kinds of coffee making tech...)

Hi Tom,

Excellent point re: gravity vs. vacuum. I've tweaked the review to clarify.

Thanks so much for the feedback.

Best,

Steven Leckart
Editor, Cool Tools

The vac pot process is different from the Moka process referenced above.

In the Moka, steam pressure in the lower boiling chamber forces the hot water up through the grounds via a pickup tube that reaches almost down to the bottom of the lower boiling chamber.

The coffee grounds swell as they are saturated with the boiling water, but they are confined (and hence tightly compacted) in a middle chamber between two perforated plates. The brewed coffee moves up through the grounds, through small holes in the top screen plate and then up the vertical tube (the tube vents is just below the lid) into the coffee reservoir chamber. The brewed coffee burbles out top of the tube, spills down, and fills the reservoir.

The gurgling sound starts when the water level in the lower chamber is down the point it’s almost below end of pickup tube. At this stage in the process it’s no longer just hot water entering the pickup tube, but both water and steam. The water/steam fluctuations cause the characteristic sound.

If you'd like to try a very smooth, low-acid coffee, try cold brewing (http://www.toddycafe.com/shop/product.php?productId=67). I was introduced to this by a co-worker. As soon as I sampled it, I went and bought one of these. I'll never go back. The coffee is so smooth! It has about 2/3 less acid than regularly brewed coffee and you can store your home-brewed concentrate for a couple weeks in the fridge with no problems, or take it to work in a thermos. Wonderful stuff.

I'm looking for the best HAND (ie non electric) grinder to properly grind my coffee for this device, as well as for standard drip. Any suggestions? thanks,

Jesse-
The good hand grinders are German/Dutch/Czeck ones from Zassenhaus, Dienes, Armin Trosser, and (I think) KyM. Zassenhaus is the only one that is still in business, as far as I know. Most people looking for these grinders buy vintage ones on Ebay. I have several vintage grinders, and one newish Zassenhaus. I use the Zass more than any others because it grinds faster. This makes a difference when you use it every day, particularly if you are grinding enough to make more than one mug of coffee.

Hand grinders are adjustable. Some will grind fine enough for espresso machines, or even Turkish coffee. Ones that cannot grind that finely are fine for drip, french press, and vacuum pot methods. New Zassenhaus grinders should be able to handle all methods. With vintage grinders, you can't tell until you try. There is a company, http://www.orphanespresso.com , that tests and sells hand grinders. They sell the non-espresso-capable grinders for much less.

Keep in might that a lot of Vintage hand grinders have a pretty low capacity. You'll want to medium-sized one to grind enough coffee for a vacuum pot.