| Carvin "Icon" soapbar pickups are okay for fretless. They are a darker sounding dual-coil pickup, and they sound like they have a tone capacitor rolling off the treble at all times. They also have a very hot passive output. This brings a lot of midrange and "mwah" to the sound, but the upper midrange and treble isn't as open as it could be.
If you like a lot of treble detail, these are not the right pickups. This bridge pickup is especially hot and dark for my tastes. However, the Carvin H50AS comes in the same shape but it's a stacked-coil humbucker, so it has a lot more treble detail and character. These work okay in pairs, and have a bright tone similar to a single coil but with a bit less fundamental.
One H50AS in the neck position will work very well with one Icon soapbar (model "SP-N", the neck pickup model) in the bridge position. You'll get a great deep tone with lots of detail and a nice variation between both pickups, which brings out their best qualities.
There are many other great pickups for fretless, including SGD, Delano, Villex and Bartolini. But the Carvins are very affordably priced, and they are a great way to get started. I can offer more information about the other brands, if you are interested.
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fretless bass, passive pickups, raw exotic woods
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