The Shelter 901 has been called the best cartridge available today, and in many ways, this might be true. It is easily one of the better cartridges I have heard. The 901 is an excellent cartridge, but as with any other component, it has a sound of its own that may or may not be the best match for your system or your tastes. It comes in a nice wooden box with an assortment of mounting screws, and it has tapped threads and includes a stylus guard that helps make mounting the Shelter on your tonearm a snap. Even though the 901 is rated as having 0.1 mv less output than the Koetsu Rosewood Signature, it seems to output almost as much as the 1 mv vdH Black Beauty. There was plenty of output from the Shelter to drive the excellent CAT Ultimate preamp below the "noise threshold", or about 2 o'clock on the volume control. The Shelter 901 is not overly particular about VTA, but you'll know you have the right VTA when the center image locks in. Loading at the recommended 100 ohms into the CAT preamp worked very well.
Compared to the Black Beauty, the 901 is harmonically richer and has a better low end. The Shelter’s midrange and treble falls between the Rosewood Signature and the Black Beauty tonally, but keeps the Koetsu's superior harmonic integrity. The 901 is also more dynamic than either of the others. If you find the Koetsu sound a bit too sweet and syrupy but want a touch of warm musicality without a hint of listener fatigue, the 901 might be ideal. Based on reports from another listener, the 901 is similar to the Koetsu Rosewood Signature Platinum from about 100 Hz and up. Addendum: After hearing the RSP at length in my system, I can confidently say that the similarity between the 901 and RSP ends with the word "cartridge". Except for the bass, where the 901 is one of the best, the RSP is filet mignon compared to 901 sirloin.
The bass reproduction of this cartridge is nothing short of reference quality. It is hugely dynamic and detailed without being dry and lifeless. This is the first area that drew my attention. I heard bass detail on familiar recordings that was a revelation. A difficult area for some cartridges is maintaining upper frequency performance when the bass is strongly present, and the Shelter manages to keep everything intact and clear when the music is really rocking. So impressive is the low-end performance that on recordings with well-recorded acoustic bass, it is easy to "see" the actual instrument in the room with you. This is rare.
The treble performance deserves special mention, too. After break-in, which was about 40 hours, I consistently got the impression that the 901 got everything out of the groove. There was a very detailed presentation that always seemed to offer every fundamental and every harmonic without any blurring or loss of performance as the bass or midrange became complex. Cymbals were naturally metallic, never degenerating into white noise on good recordings. It was a simple matter to follow any instrument or voice throughout a piece. When several voices were present, it was also easy to differentiate between them. The treble presentation was never unnaturally hard or glaring, though. Never. The soundstage presentation was very good, although not as good as the Koetsu at precisely localizing each voice or instrument.
The midrange had some of the “Koetsu magic”. Voices and instruments were lightly sweetened, and female voices in particular had a nice accessibility that made listening to them very enjoyable. Being very critical, one could say that there was a small difference in the presentation of the somewhat warm midrange compared to the relatively dryer and more analytical bass and treble. While I heard this slight discontinuity in my system, another listener in another system might judge it to be a perfect balance. This cartridge might be ideal when used with older, classic tube gear that has a soft sounding bass and a slightly dark treble, or in a system that needs help in these areas. In a system that tends more towards “ruthlessly revealing”, you might prefer a presentation that is more balanced from top to bottom. But this is really a matter of fine-tuning a system, getting that last 1 or 2% after you have dialed in your cables and listening room. On the other hand, the 901 is good enough to warrant revisiting many of the choices you've already made in building your system. The Shelter 901 offers a wonderful set of attributes, and could be an excellent source component to build a system around. The overall quality of its performance makes the 901 suitable for use in even the finest high-end system, although careful system-matching is highly recommended.
Overall Rating: 8 LPs