Andy Kim - Needle Clinic

My Kleos sounded a little off lately, so I thought it should be checked out. I sent it to Andy Kim. It turns out all that was needed was the stylus required a cleaning and polishing.

Glad you got it looked at by an honest guy and kudos to Andy Kim (whom I hadn't heard of before this thread).

I can no longer count how many times I've had cartridges shipped to me for inspection, supposedly because (according to the owner) they were wearing out or defective, only to find that a simple but thorough stylus/cantilever cleaning brought them fully back to life. It's always the first thing I check, and usually the last that I have to. :-)

Stylus cleaning after every side is mandatory to maintain performance, especially with cartridges having advanced stylus profiles like the Kleos. Modern styli rely on very small contact radii for their clarity, HF extension and low level detail retrieval. The tiniest amount of smudge interfers with that.

This is true even if your LPs are very well cleaned. As JC taught me years ago, a perfectly clean groove will shed vinyl particles. The heat and pressure at the stylus/groove interface bond these to the stylus. Cleaning after every side is the surest way to avoid incremental buildup of smudge.

Routine use of a Magic Eraser (followed by a soft brush or a dunk in Xtreme Phono type goo) will maintain a stylus in as-new condition.

Bif,

I can't speak for Lyra, but some stylus profiles do maintain a useable shape without serious sonic degradation longer than other shapes.

The worst case would be a conical stylus (which has a spherical cross section across the groove contact points). Even new, such profiles have limited HF extension and detail retrieval, since a contact diameter equal to the width across an LP groove is many times larger than the radii of HF's and lower level details. These "fat" styli can't trace shorter wavelengths and slur right over them. Worse, with every bit of stylus wear, this contract radius grows progressively larger. The sonics of a a conical stylus, limited to begin with, deteriorate steadily from hour 1 of play and constantly thereafter. This is exacerbated by the fact that, when new, all pressure is concentrated on two single points of contact, so wear from friction will be faster than on styli that have vertically longer contact surfaces.

Elliptical styli are better. They have shorter contact radii (in cross section) but longer contact surfaces (vertically). Their wear from friction will be slower and the resulting sonic deterioration less.

Better still are micro-ridge styli, as used by Lyra, ZYX and others in higher end models. The cross section of a microridge stylus looks something like a football with a tiny rod poking out at each end (the ridges). These ridges, which is what the stylus rides on in the groove, have a very small diameter, as small as 3 microns. As they wear down, the shape of the remaining portion of the ridge remains... wait for it... UNCHANGED! Those 3 micron contact radii are maintained until the ridges are entirely worn away. IOW... virtually NO sonic degradation. Further, the ridges are parallel to the groovewalls, making a very long contact surface (vertically). Friction is thus spread over more diamond surface, reducing the rate of wear.

This, by the way, explains the high sensitivity to SRA adjustment of micro-ridge styli, whereas conical styli are almost entirely indifferent to SRA.

So... am I surprised that your Kleos shows so litte wear? Not at all. Enjoy!