MM Phono Input impedance change 47k to 100k ohms
My first experience with a 100K load was with a Grado TLZ. Word was around that it really liked 100K. Sure enough, it sounded far better at 100K than at 47K. Since the TLZ was/is not even an MM but is an MI type, I never did assume that 100K would be better for (all) MM cartridges. Some will sound better at that load value; some won't. But I never found 100K to sound "bad", either. In the separate MM only stage that I use in one of my systems, the load R is 100K. In my other system I use a Manley Steelhead with its fixed load of 47K for MM. I did buy resistors to convert it to 100K but have not found the compulsion to make the change. I've got enough other bits of audio repairing to do before I do that. |
@chakster...I just pulled out my dealer binder from Grace. The literature for the F9E & F9E Ruby, state 47,000 as the recommend load. I don’t like F9E cartridge compared to better Grace and to some better MM. I think F9E is nothing special. 100k Ohm is mandatory for Shibata Type (F9F) or Line Contact type (F9U) stylus profile designed for CD-4 records to reproduce highest frequency. I think Grace couldn’t name is Shibata because of Victor’s Patent. So they call it Discrete-4 and Unility-4 instead. I’m curious, if you was a dealer of the Grace cartridges in North America, did you ever get F12, F14 or LEVEL II models ? There are so many different models with different cantilevers and styli made in the 80’s by Grace ... and almost no information about them. Here is what I have (Experimental version of Ruby for LEVEL II, extremely rare Ceramic cantilever for F14 and LEVEL II, Two MicroRidge versions for LEVEL II, one with Boron Pipe cantilever ... and some more). |
