MM Phono Input impedance change 47k to 100k ohms


The well-written AudiogoNer Raul states that the Grace F9 Ruby MM cartridge is best matched with an input impedance of 100k ohms vs the standard 47k ohms. May be a dumb question, but is this a simple resistor swap that I might be able to handle or should I best take the preamp to a technician?
elunkenheimer

Showing 2 responses by rauliruegas

Dear Gentlemans : Through the years I always ( time to time ) " think " things out of the " book " that's why I re-discover the MM/MI alternative and when I gone inside the alternative I made the same about the load impedance for these cartridges. Over the years too that time where I think and take actions in an non-orthodox way gives me some fails and some rewards, the MM/MI alternative is one of this rewards.

The Grace 9s different models shares the cartridge same motor and here you can read the FR at 100K with 80pf:

http://www.vinylengine.com/library/grace/f9.shtml

this is the response of those cartridges for CD-4 or NOT.

The Empire 4000 series was designed to run at 100K too and many other MM/MI cartridges. I tested several load impedance options with different cartridges even several cartridges that were designed for 47K and even these ones performs better at 100K.
Problem is that even on those times only a few phono stages came with 100K option where the 47K was and still is the standard but even knowing this standard I tested higher load values ( non-orthodox. ) and till today no one I know is running at 100K posted any kind of " anomalies " in the quality cartridge performance level.

I agree with Hifitime: no one has to belive in me what IMHO has to do is to test it to try it and decide about.

Btw, Elenkeinheimer you can try 100K and if you don't like it you just return to 47K: no big deal and remember that as critical is the MM/MI load impedance as critical is the MM/MI capacitance that must be mated in between.

Hifitime, certainly you can speak about ADS speakers but IMHO you can't speak in specific of my ADS loudspeakers not only because nothing of what you posted happen in mines but because you don't know maybe I can say: you don't even can imagine the quality performance level of my system. If in the future you could have the opportunity to live that experience IMHO you will be " heavy " surprised.

When I made and make " discoveries " that's because I don't believe in " standards " like that 47K till I prove to me that that standard is " right ".

There are almost no-rules about because as Lewm knows several times what in theory things have to be in practic/live does not happen and that theory can't be confirmed.

Audio and analog LP playbak in specific is terrible imperfect at least this is what I learned and I'm still learning.

That 47K sounds good does not means that other load impedances, as 100K , can't sounds better.

Finaly, each of our systems is different and more critical that that is that our music sound reproduction priorities are different too and that's why different opinions.

My advise is: test/try it always and decide.

Regards and enjoy the music,
R.
Dear Calbrs03: That's all about: test and decide, good!!!

Regards and enjoy the music,
R.