Among all the cartridges (>100) I've inspected for friends in the past few years, only 4 showed obvious stylus wear. Interestingly, 3 of them were installed on air-bearing arms, the other on a tangential pivoted arm. The photos below are from the most recent case, showing a chunk in the right-channel side of the stylus chipped away. According to the owner of the cartridge, he followed the advice from an "expert" and adjusted the air pressure to the arm lower to get "fuller bodied" sound.
I believe there is nothing intrinsically wrong with those arm designs, though one should definitely pay more attention to the setup and maintenance aspects. Especially with the air-bearing type, any issue in the air transmission lines can put huge stress on the cartridge and its stylus.
在幫朋友檢視過的這麼多唱頭之中,真的見到針尖磨損的情況,其實非常少,嚴格講起來算有4個。但無獨有偶,其中3個是裝在氣浮正切臂,而一個是裝在支點正切臂。3支氣浮臂是不同廠牌出品,所以並非哪一支臂的特有現象。附圖是最近觀察到的一個例子,可以看到,針尖右聲道那一側(圖1,2裡的左側),有明顯的缺角。根據主人的說法,他按照一位「達人」的建議,將氣浮臂的壓力調比較低。可能因為如此,在播放唱片唱臂向內移動時,外側(右聲道)一直承受比較大的壓力。
我在之前(音響論壇348期)也說過,直線正切臂(氣浮臂包含在內)的先天缺點之一,是所有的質量都在支點之前,因此有側向力時,唱頭針尖會受到很大的壓迫。而支點正切臂,這方面雖然比較不會造成問題,但因為機械構造複雜,可動部分受到灰塵或溫濕度影響,動作受到阻礙的機率會比傳統支點臂來得高很多。因此,使用這類唱臂的人士,應該要定期檢查保養,特別是氣浮臂,整個供氣的通路一定要確保清潔通暢,壓力要合乎原廠規格。而且在聽到有任何循軌異常時,立刻停止使用,做全面的檢測。
至於唱頭的健康狀態,我一直主張要每半年測量數據,持續追蹤變化。如果有明顯改變,就應該拆下來用顯微鏡仔細檢查有無異狀。這對正切臂的使用者來說,尤其重要。