Best SUT For Van Den Hul Crimson Stradivarius cartridge
@elliottbnewcombjr what is the difference between Impedance selector and load selector? https://www.ebay.com/itm/KONDO-AUDIO-NOTE-AN-S7P-MC-STEP-UP-TRANSFORMER-JAPAN/123923446228?hash=item... Thanks |
Kanchi, Your linestage adds 17db of gain, according to the Cary website. So, with the Ypsi and the Cary linestage you have a total of 56db (39db + 17db) of gain, which is a voltage step-up of about 630X. Thus when the cartridge is putting out 0.95mV, the SLP linestage is putting out about 0.630V. Bear in mind also that the rating of 0.95mV is for the frequency of 1kHz and the stylus velocity of 5cm/sec. A large fraction of "music" will produce transiently higher output V. For many amplifiers, that would be sufficient to drive them to a decent fraction of full output, at least. However, your Cary 211 amplifiers require 2.0V for full output, according to Cary. Therein lies your problem. The 211 is a difficult tube to drive. In lieu of buying a SUT, you could instead replace your linestage with one that produces more gain. It's not hard to find excellent linestages that are in the 20db to 25db range for gain. That would eliminate a whole slew of problems with matching a SUT. And based on the typical cost of high end SUTs, the cost differential is not that great. With a megabuck phono stage like the Ypsi, you don't want to match it with a bargain SUT. You stand the risk of losing the qualities you've paid for. To answer your question put to Elliot, with any SUT, what you want to know is the turns ratio. Knowing the turns ratio or voltage gain afforded by the SUT, you can easily calculate the load seen by the cartridge, if you know the value of the fixed load resistance built into the phono stage (typically 47K ohms, which is what Ypsi uses). If you can find a SUT with a 1:5 turns ratio or a 5X voltage gain (there are calculators on line if it makes you feel better to convert voltage gain to db), the load R seen by the cartridge is 47K ohms divided by the square of the turns ratio. Thus for 1:5, the quantity is 47K/25 = 1880 ohms. For a 1:10 SUT, much easier to find, you have 47K/100 = 470 ohms. Both loads should be easy for the vdH to drive. If you don't like the idea of replacing your linestage, I would suggest you borrow a SUT with a 1:10 ratio and see how it goes. 1:10 might be fine. |
It's something like EMT output So stepups used for EMT should work well. Like this one: https://www.emt-tontechnik.ch/files/productfile/Flyer-STX.pdf |
@lewm thanks for all the explanation. I have read about 10-20 articles detailing all about impedance (47K)/square of turns ratio and how to modify the load using parallel resistors at the out put and in put. If I use 1:10 turns ratio, the cart sees 470 ohms. I also know that, I can calculate the parallel resistors I need to use to decrease the loading. What I am struggling to understand is the following, what is the best loading for a given cartridge. For example: the VDH Crimson Stradivarius says optimal load impedance of 20 - 600 ohms, which is such a large range. I contacted VDH to tell me the exact internal impedance of the cartridge. If they say the internal impedance of the VDH is 20 ohms. Then how do I use that number to come up with the best loading. |
