Without a Filter - oFi:

A pipe can be smoked with or without a filter. If you have a pipe with space for a filter, you can also leave the filter out and smoke without one. The reverse is not possible, of course. With filterless pipes, the bore is not large enough.

When smoking without a filter, the smoke enters the mouth directly and unimpeded. This can make the smoke hot, moist, and intense. There are quite a few pipe smokers who prefer to smoke without a filter. Almost the entire world smokes without filters. Germany is an exception. However, even here, some pipe smokers swear by "oFi." The taste experience is perceived as clearer and more nuanced than with a filter.

A noticeable difference is the draw. Without a filter, the draw is very easy and more directly controllable. You can feel excessively hot smoke directly on your tongue.

Filter Material - Paper Filter, Balsa Filter, Meerschaum Filter, Activated Carbon Filter

The filter effect varies in strength and spectrum of effectiveness depending on the filter material, quantity, and construction. The simplest type of filter is the paper filter. The smoke passes through the filter almost unimpeded. However, moisture and larger particles are absorbed or blocked. The temperature of dry smoke is often more tolerable on the tongue.

The balsa filter consists of a highly absorbent piece of balsa wood. It is precisely cut to fit the filter chamber and has lateral channels along which the smoke flows. The remaining smoke passes through the filter. The balsa filter can absorb a significant portion of the condensate and pollutants. For sensitive palates who still want to experience the full spectrum of a tobacco, balsa filters are the right choice.

Meerschaum filters consist of small pieces of meerschaum encased in a paper tube, sealed at the front and back by perforated caps (usually ceramic). With this type of filter, virtually no smoke passes through the filter. Meerschaum is a rare and porous silicate, primarily mined in Turkey. It is highly absorbent and can also absorb condensates, tars, and other contaminants. Furthermore, it is very neutral in taste. The paper tube also readily absorbs moisture.

The most common pipe filter material is the activated carbon filter. Its construction is the same as that of meerschaum filters, except that the paper tube contains pieces of activated carbon. Activated carbon is a proven material for purifying liquids and gases. The smoke is also effectively purified within the filter. Depending on the pore size and the amount of activated carbon, the filter properties vary. Therefore, not all activated carbon filters are created equal.

Filter Sizes 

The filter size depends on the pipe's bore. 6mm and 9mm are common. However, 3mm, 4mm, and various special sizes are also available, though they are very rare.

With smaller bores, keep in mind the draw resistance, which can increase significantly with a thick filter.

Other Filter Options 

Filter Crystals, Filter Stones, Sieves, Filter Granules

Besides inserting the filter into the filter chamber between the shank and mouthpiece, there are many other filtering options. These are primarily achieved by placing the filter in the bowl.

In this case, the filter is placed in the base of the pipe before filling it with tobacco. Porous filter crystals and meerschaum granules have proven effective. However, sieves and stones are also used.