The KF300 Swissgold filter is without a doubt the best way to make a filter coffee for one person, and probably even for two people; just buy 2 KF300 Swissgold filters and get on with it.

But what to do where you want to make coffee for say 6 people?  Well, we have observed that the KF4 12-cup Swissgold filter has not sold nearly as well as the KF300.  You will recall our efforts a couple of months ago to purchase and test a number of filter coffee machines from Sainsburys, John Lewis, and Amazon, all of which ended with unacceptable performances, and in almost all cases we discovered that a number of manufacturers have made sneaky minor changes to ensure that the KF4 Swissgold coffee filter no longer fits their machines, if only by millimetres.

With this change a number of these machines now mysteriously sport their own 'permanent' filters.  Permanent filters they may be, but if you put them alongside a Swissgold filter the differences are significant.  Some manufacturers clearly think that a fine nylon mesh filter meets the definition of 'permanent'.  Anyone who has used one will know this isn't the case, the fine nylon mesh is notoriously fragile and becomes increasingly so with age; the heat makes the nylon brittle.  More importantly, and this isn't some highly theoretical coffee boffin's objection; passing the coffee through nylon really taints the coffee badly, especially when new.  The next group of 'permanent' filters are stainless steel, which are durable but they do impart a metal taint.  In the final category you have stainless filters that have been gold anodised and these are the best of the imitations but they are no where near as fine as the Swissgold and the gold plating is not 10 microns thick.

Importantly the Swissgold is not a mesh constructon, but actually a sheet of metal that has had thousands of fine holes precisely cut in it with a laser.  When you hold the Swissgold filter up to the light you will appreciate just how precise the process is; none of the holes are ever 'missing', the pattern doesn't vary or wander, the holes are incredibly fine, and thanks to the laser cutting rather than punching the edges of the holes are all perfectly smooth with no raggedness.

What does all this mean in terms of how it improves the taste of your coffee?  Simple.  Swissgold filters hold back almost every grain of insoluble material yet allow all the colloids which carry the coffee 'taste' through into your cup.  The performance difference is significant.  For the avoidance of doubt they also out perform paper and cloth filters, eliminate the ongoing cost of filters, and ensure that you never find yourself out of filters yet desperately needing a coffee.

Additionally, almost without exception the filter coffee machines on offer are not calibrated to ensure the correct brew temperature, between 92-96C, and fail to brew fast enough (within say 6 minutes).  We also have concerns about selling machines with elements that keep the brewed coffee warm as even the finest brew in the world quickly turns to a vile treacly tar, not dissimilar to instant coffee when left on a hotplate to keep warm.  We know these kind of features are sold under the 'convenience' banner by the marketing men but we firmly believe that convenience is a euphemism for sacrificing quality in return for an easy life.  If you want convenience Londinium isn't the place for you.

Well, finally we have found a product that delivers after rigorous testing and evaluation.  Unfortunately there is a lead time of about 6 weeks on it, so expect to see the product we have identified as the ideal solution in stock here in about a month's time.  If you are considering purchasing a high quality filter coffee machine to brew around 10 'nominal' cups we would strongly suggest  that you hold off your purchase decision for another month.