Yep, your correct!
Thanks to all for the support!
Cartridge Loading.....Part II
I read last night the below noted discussion with great interest. It's a long post but worth the effort and I found it interesting.
It started me thinking about the amount of loading on my moving coil cartridges. Years ago I purchased my first MC Cart, a very nice Benz Micro Glider, medium output of 0.5 mV as I recall. At that time I inquired about loading here on Audiogon. I was convinced, via discussion, by another member, that 300 Ohms was the magic number, so I thought.
Time moved onward and my second MC Cart is currently a Lyra Delos, again medium output 0.6mV. Both carts had Boron cantilevers', 6 nines oxygen free copper coils and line contact diamond stylis. When I set up the Delos I did not change or even consider 'loading' changes. That was a grand mistake.....
Well, thanks to this specific thread I started to second guess myself . (you can do this when retired and more time is on your hands....)
My take from this recent thread is as follows. Load at 100 Ohms or at 47K Ohms with a quality MC cartridge. I opened up my Conrad Johnson EF1 Phono Stage this afternoon. Found it set at 500 Ohms loading. 100 Ohms is not an available setting. Damn...All these years I've been running the wrong loading, and on two carts, back to back... I don't recall why I set the loading at 500 Ohms. Faulty logic.
I reset the loading to 47K, buttoned things up and called the wife in for a listening session. Sure as heck both of us noticed the highs were crisper and more 'apparent' than in the recent past. Not a huge difference, but yes, a difference.. Hard lesson learned!
So, you smarter folks on this site might banter amongst yourselves, but in reality there are those of us, behind the curtains, reading and listening! I just wish I hadn't wasted all those years listening to the incorrect load setting!
Ending with a sincere thank you very much!!
Lou
Showing 7 responses by quincy
Well, this has been an interesting thread. I do appreciate everyones response in regards to loading. I did a little internet search and here is what I came up with in regards to loading. I am quoting from Analog Planet, a site of which I've never heard of prior to today.
"The Delos, machined from solid aluminum billet, features a 2.5µm x 75µm Namiki microridge line contact stylus, a solid boron cantilever and coils of 6-N high purity copper. Output of the 7.3 gram cartridge is a relatively high 0.6mV@5cm/sec while internal impedance is moderately low at 8.2 ohms. Like other Lyras the Delos uses a yokeless, Neodymium disc direct magnet system. The connection pins are silver plated. As with any line contact type stylus, correct VTA/SRA is critical to optimizing performance so a VTA adjustable tonearm is recommended if not mandatory. Compliance is approximately 12x10cm/dyne at 100Hz. Recommended tracking force has a narrow window of 1.7g—1.8, with 1.75 “preferred.” Recommended loading is between 91ohms and 47kOhms determined by listening. VTA is 20 degrees, which Lyra says is achieved with the arm parallel to the record surface. As with other Lyras, the generator is integral to the body as opposed to being a completed mechanism inserted into a body. The result is better mechanical grounding, energy transfer and inherently correct alignment of the generator and body. You can determine the “mathematically correct” loading according to Carr’s instructions by determining the total capacitance between the Delos and the phono stage. While the ultra low inductance of moving coil cartridges makes capacitive loading far less critical than it is with MM cartridges, there remains a relationship between capacitance, load value, bandwidth and the amplitude of the ultrasonic resonance. Usually though, a setting of 10X the internal impedance is a good starting point, which is why Lyra species 91 ohms as the low, which is just above 10X the Delos’ 8.2 ohm impedance. According to the instructions if your cable’s capacitance is 100pF per meter, for instance, loading at 390 ohms will suppress the peak to 3dB while 200 ohms will suppress it to 0 at the expense of slightly poorer phase response and reduced dynamics. I went with 500 ohms but listened at 100 ohms as well, which is where I preferred it. One interesting new design wrinkle here is a new body angle and a “pre-angled” damper system that aligns the coils and magnetic circuit with the application of the proper VTF. Most cartridges, Lyra claims, provide this alignment only when no tracking force is applied." I dug out my manual for my C-J EF1 phono stage. (btw I run the phono stage into a C-J Premier 17 LS, a very high quality tube preamp I acquired from a good friend 20 years or so ago.) The avail loading is: 200 ohms, 500, 1.9K, 9.6K, and 47K. These are set by dip switches. One sentence I will quote from the manual. "The factory preset 47K load (all switches off) will be best suited to most cartridges." C-J does not mention MM or MC carts in any of their instructions....go figure. I am running Audio Quest King Cobra interconnects throughout the entire system chain of equipment. I have no idea how to calculate the mathematical correct loading; and even if I could, it may not be avail in my phono stage. Since my Pre amp and Amp are tube C-J equipment, I'm hoping C-J did all the 'correct engineering' so their equipment runs together in harmony. The way my system is stacked it's a hassle and 1.5 hr job to switch the loading, which requires me to get on a ladder...no fun. For the time being I'll leave it at 47K. If I decide I don't like it, I'll switch to 200 ohms and call it a day. I really don't want to 'play around' with loading. Just find the best setting and leave it alone...Thanks for all the feedback! |
Atmasphere......The Ah-Ha moment! http://www.atma-sphere.com/en/mp-1.html Is this the company you represent? I apologize that I did not recognize you as a tier one supplier of high quality phono stages. I will study your web page further. Thanks for being involved with Audiogon and sharing your knowledge!! Lou |