The MMCx cartridges sound depends very much on the weight or load. 0,8gramm to 1,5gramm, depending on its construction. You can play with the load... ... or get a good libra. The RIAA is also important. Some use filter caps on the input side against noise. This is not good. You have a schematic?

In my experience B&O cartridges have a lower output than other makes which can make a direct a/b comparison show the B&O as performing below that of another make. If you compare with a Shure cartridge it will sound much better initially. What RIAA stage are you using - try playing with the settings, I have mine on a high output MC setting rather than MM and it sounds very good

Are you comparing a B&O cartridge with 30-40 years old rubber suspension with something factory fresh? Martin

It's interesting you use the phrases "sounds nice" and "lacks in terms of highs and clarity" as, unfortunately, to me, that describes the sound of the TX2 turntable and its similar brethren (such as the 5005, 5500, 6500 etc.). Hence, I would personally say that the problem is the turntable. Those final era linear trackers are lovely things to behold and use (and are easy to service, which is a rare thing to say about B&O!) but I have never never found any of them to sound as good as the same era radial trackers. In your shoes, I'd keep the MMC3 and buy an RX2.

Thank you all for your inputs. Let me share a few more details: I'm comparing the MMC3 with the Ortofon 2M Blue or the Shure V15 type IV at the Denon DP-3000/SME 3009 turntable (have a B&O adapter). Yes the Ortofon is new but the Shure is actually older than the MMC. The difference is very clear: the MMC lacks resolution and clarity. But I'm wondering if it is just the needle: When I test it with the Ortofon Test Record is distorts on tracks above 60 micro meters peak, or above 300Hz lateral + 14 db in the HIFI sound test record HFS75. It also gets dirty very easily. Then my question is: Is the MMC3 (or the SMMC3) typically comparable with the Shure V15 type IV or the Ortofon 2M Blue or do I need to $$$ upgrade to the models 2 or 1?