Benz Ruby 2 v.s. Shelter 901


Has anybody compared the Ruby2 low output to the Shelter 901 in their home system. What is the optimum amount of gain for the Shelter- should need less than the ruby is what I'm thinking.
reb1208
The shelter is a fine cartridge for the money but it does not have the refinement and top to bottom balance that the ruby does. If you have the shelter in your system you could be perfectly happy forever-unless you put the ruby in and hear the difference. This is a pocketbook decision. Remember it's about the music and one can get hung up on incremental improvements. Not to mention going broke. Spend more money on records and less on hardware is my motto.
Thanks for a wealth of information, Twl. And thanks for pointing me to a source with more information, Aisip. I will do some search to get more "educated" about this subject matter! :-)

FrankC
Ooops! I was trying to respond to Gundam91, not Reb! Sorry for the confusion.
Reb,

Let's give TWL a break! This guy must already be exhausted answering most of the analog-related type questions here in "GON." Reb, go to the GON's homepage and in the "SEARCH" area, type "SHELTER 901". TWL has already answered the questions you have (compliance, tonearm recommendations, etc..). I learned a few secrets, tips and tweaks reading TWL's responses. I am a proud owner of a Shelter 901. Simply put, it is the finest cartridge I've ever heard. Go for the Shelter and use the money you save to buy more records! Believe it or not, this is the best time to be playing records. Most recorded masterpieces are now being reissued using the finest vinyl formulations and the best associated recording equipment. Analog never sounded better! Good luck and happy listening!
Frank, , the term "compliance" relates to the flexibility of the suspension of the particular cartridge. Generally, a number of 12cu or under is considered low compliance. Low compliance means a stiff suspension, and often accompanies a heavier cartridge. Over 12 and under about 25 is medium. And over 25 is high compliance. Actual numerical values of these definitions may vary by some opinions, but these are approximately the values.

Many observe the proper guidelines for arm/cart resonance matching, which would give a combined mass/resonance in the 10Hz-12Hz area. But this is not the only thing that needs to be accounted for. Compliance will affect some tonearm designs in different ways. For example, you don't put a super-high compliance cart on a high mass tonearm. You don't put a super-low compliance cart on a low mass tonearm.

What I referred to above was low compliance incompatibility with certain unipivots. The lack of rigid horizontal orientation of these arms precludes use of very low compliance carts, due to the propensity of the cartridge compliance to cause the tonearm to change azimuth during play. Outriggers and fluid damping, and higher weight "cups" have mitigated this somewhat in the better designs, but the basic rule holds in the more extreme cases. All unipivot designers are aware of this, and readily admit this mismatch with low compliance carts. I even recently read an interview with Harry Weisfeld, the designer of the JMW arms, and when asked about the disadvantages of unipivot tonearms,he said in the interview," as the arm rides up and down on the record, the aspect ratio can change. In other words the arm tilts."

This is not much of a problem with medium and high compliance cartridges, because they do not generate the same amount of deflection to the arm as a low compliance does. So, the result is that medium and higher compliance carts are better matches for these types of arms than low compliance ones.

Very low compliance carts like the Denon DL103, present a challenge to even the better gimbal-bearing arms, due to the energy transmitted to the arm and bearings.

In the case of a "borderline" match, where the numbers are on the edge of compatibility, it is potentially a problem. You should not go there unless you are willing to sell the cart or the arm in case of a mismatch.

For a rookie, the best bet is stay in the "happy medium". A medium mass arm, a medium compliance cart, will usually provide good results. When you start to get into the exotic stuff, you should have gained enough knowledge and experience to make the correct matching decisions.

That was a copy of one of my previous posts in the archives on this subject. To address your particular question about arm masses and examples, generally under 7 grams is lightweight, 7-11 grams is medium weight, and 12 or over is heavy weight. Again, these are generalizations, but they are pretty accurate. Like a Rega tonearm with 11 grams effective mass is on the high end of "medium" and could be used with a lower compliance cartridge in many cases. Most arm manufacturers will give the effective mass spec on their spec chart for the arm. You can compare that to my generalizations above for the category it would fall under. There are also some charts on the net, that I couldn't find just now, that give resonance matching data.

For some examples of arm types, a Rega is a gimbal-bearing arm, a Graham or JMW would be examples of unipivot arms. And of course, an ET-2.5 is an example of a linear tracking arm.

I hope that helps you out.
Twl,

Could you explain more about some of the terms you used, like compliance? What's considered low compliance? What's the importance of that? What are some examples of medium mass arms, high mass arms, unipivot arms, gimbal bearing arms, etc.

Thanks!
FrankC
The 901 has output of about .5mv, which I think is higher than the Benz. As far as which you'll like better, it depends upon your personal taste, and it may depend upon the arm you are using. The Benz would be a better match for most of the medium mass arms available. The Shelter prefers a little heavier arm, and gimbal bearings serve it better than most unipivots(with a few exceptions). This is due primarily to the lower compliance of the Shelter cartridges.