I'm not really into stock Haussel MM-pickup - it just too "thin"-sounding by itself.
I enjoy sound of Wojtek Pilichoswki who uses Bartolini soapbar pups or (ha-ha) Or Lubianiker who uses Aguilar DCB soapbars. Both using Aguilar OBP-3 pre, so...
I think the stock ones are Sandbergs own. The MM position is quite far back toward the bridge to be used by itself without boosting the bass IME and you'd probably find any replacement would have the same problem. The TM4 that I had sounded much better in that respect, as the MM pickup was a little further towards the neck.
I'm not sure what the Sandberg MM's sound like compared to my Delano or Haussel but the Sandberg P pickup is definitely more scooped than the Delano P.
I must admit that I fancied replacing my set with the Nordstrand Big Man and NP4a but for me the Delano's are working great now.
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