MC cart, can I use MM phono preamp?


I am thinking of a Shelter 501mkII cart, but I only have a preamp with a MM stage. Could I use that cart with the MM only pre or am I better off looking for similiar valued, classed MM cart? If so which one would you recommend?
crazyravr

Showing 2 responses by dougdeacon

Wise advice from Swampwalker. Using an LOMC+SUT well is not simple, using them badly is.

Also agree with Stanwal's advice to upgrade your cartridge last. Table, arm and phono stage must be good or you just won't hear what a costly LOMC can offer. As he also noted, a cartridge has a limited life span. It isn't prudent to upgrade if the rest of your front end won't reach an appropriate level before it wears out. Tables, arms and phono stages are forever, so they're a sounder investment.

Further, an entry level cartridge can sound amazing with a good table, arm and phono stage.

Extreme example: I'm currently demoing a $125 MM, temporarily setting aside my $8K (retail) LOMC. My table, arm and phono stage retail for ~$19,000, a rather silly 152 times more than this MM cartridge.

How does it sound? Damned impressive, quite the equal of any $1,500 LOMC that I've heard.

OTOH, when I play my fancy LOMC with lesser TT's, tonearms or phono stages the best I can hope for is that it'll sound pretty good, which isn't much for the price. Sometimes it sounds boring. Most often it reveals the weaker component's flaws and the net result is unsatisfactory. Now when everything's right the LOMC is utterly glorious, light years beyond the $125 MM. But everything else must be right - first.
Opaceo,

Your supposition is correct. If you compare several manufacturers' recommended phono input impedance settings for their LOMC's, you'll notice two things:
- recommended values are all over the map (ranging from 10 ohms up to 47k)
- recommended values are often a range, not a single number

All MM's and most HOMC's are optimized for 47k ohms. LOMC's are all over the place. Each manufacturer uses what they believe is best for a particular price point, desired output, desired frequency response, etc.

Frequency response is one characteristic that changes, particularly at the top end. Further, the optimal impedance may vary from one system to another, which is why many LOMC manufacturers recommend a range (ie, experimentation) rather than a specific value.

To address this, many MC phono stages include adjustable input impedance, which allows user optimization with different cartridges. An MC stage that doesn't somehow allow for this is inherently limited, in that it won't necessarily optimize with all LOMCs.

Impedance matching for an LOMC is even more critical and complex when using step up transformers, as suggested by some of the posts above.