I need help diagnosing a sibilant problem on vinyl

David256, the " high frequency spike" when a MM cart. "plays through a defect" is not inherent to the cartridge. It's the result of improper loading. Typical MM carts have a rather high inductance compared to the usual MCs. This makes them much more sensitive to the amount of shunt capacitance loading them. Too much results in an electrical resonance at the high end of the audible range. Any defect in the record that causes an ultrasonic pulse will excite this resonance and cause it to ring, resulting in a "high frequency spike". Please refer to Jim Hagerman's white paper on cartridge loading for more information on this subject.

IMO, excessive sibilance is a different animal than high frequency ringing. My experience has been that distortion in the payback chain can cause issues with excess sibilance and all the monkeying with cartridge set-up in the world won't cure it if the problem lies elsewhere. That's not to say that a badly set-up cartridge won't cause problems, it will. But it's not the end all, be all, cause of the problem. In my experience distortion is the problem. Whether it's caused by the stylus profile (think elliptical and inner grooves), improper set-up (imperfect azimuth leads to excessive IM distortion for example) or lack of transparency in the playback chain of electronics. Every link in the chain has to be addressed or the problem will persist.

John_tracy, thanks that's good information and timely. The phono section of my CJ pre amp has a noisy channel and since that's acted up I've been thinking of finally tossing in the towel on Grado Signatures and going to a Dynavector MC setup. So I'll have to think about which is the more cost effective path, paying more for a MM phono pre with loading control to use with the Grado I have or getting a simpler phono pre and new Dynavector MC.

John_Tracy - excellent post. Concur with you on all points (and with Wc65mustang).

HF ringing and sibilance are different phenomena. Calling the first one "sibilance" is a common misunderstanding and may engender further confusion.

"Sibilance" is the collective phonetic term for a family of sounds made by the human voice. A single example or type of sibilance is called a "sibilant" (plural, "sibilants"). Sibilants occur in nearly all human languages; therefore, so does sibilance.

A formal definition:

Sibilance is a manner of articulation of fricative and affricate consonants, made by directing a stream of air with the tongue towards the sharp edge of the teeth, which are held close together; a consonant that uses sibilance may be called a sibilant. Examples of sibilants are the consonants at the beginning of the English words sip, zip, ship, chip, and Jeep, and the second consonant in vision.

Credit: Wikipedia, which has a comprehensive and well annotated discussion

An audio system may distort sibilants. If it distorts them all, it may be generically said to distort sibilance.

Complaints that a system has too much "sibilance" are mis-stated; a system has as much sibilance as there are sibilants on a particular recording - no more, no less. What a system may have is the inability to play some or all sibilants without distortion. The possible causes of this distortion are many, as my previous posts and John_Tracy's latest have emphasized.