cartridge loading ?

Bombaywalla, thanks for the correction. I'll try to remember that a coil of wire moving in a magnetic field can't, sorry I mean "CANNOT put out any current whatsoever." Presumably, you learned your electronics from a better school than I. By the way, I recommend you avoid getting too close to any electric power generation equipment, just as a precaution.

Bombaywalla, Yes, The "magic" number is actually an RIAA derivative. It is a number generally used as an established "benchmark". It works not only at the line stage levels, but also commercial remastering from analog to digital format.

Based on remastering with the current commercial CD recorders in use, the actual recommended value is 300mv, as 300mv is what would be required to attain a 0db recording level with the recorder's level controls set at max. How RIAA actually arrived at that number? I can't tell you. But I would guess that SOME type of standard needed to be established.

The 325mv figure that I use, allows for a small working margin. Lord knows sometimes we need it.

Now if we could only find our original poster of this thread. I think he may be sitting back reading all of this and thinking, "Don't these guys have a life?"

Can you blame him? Ed.

Jameswei,

I stand corrected!
I realized this a bit after I hit the "submit" button. Writing too late @ night crosses wires inside the brain!

duh.
out w/ flu a few days but as i try to wade thru this, i fear i may have tried to return too soon.
i think my koetsu has an output of 0.6mv. i believe my melos phonostage offers 54 and 78 db of gain, i use the lower output since even that provides a higher level than my cd player. i am clueless about the capacitance of my various "phono" cables, altho i may have some documentation on the purist; they are all 1m. length.
i think i'm finally clear on the importance of the capacitance of the phono cable & preamp, altho i'm not yet clear on how to solve it, but i'm still struggling w/ the resistance/impedance issue: primarily i see now because of ignorance of fundamentals. i've got the electrons moving d/t the coil over magnet assembly. does increasing the value of a resistor to ground force more of those electrons to the tube grid? is this the formalism for increasing the load on the cartridge?
thanks,
jon

Hi Jon, I had that nasty flu a couple of weeks back. I'm STILL feeling the residual effects. Hope you're feeling better.

I'm confused. I looked up the Koetsu Onyx on the Elusive Disc website. It states that it has an output of 0.2mv. Is this cartridge offered with an "optional" ouput of 0.6mv also? Is the information I am being provided incorrect?

The difference between those two figures is somewhat significant. A 0.2mv output would require an optimum gain of 64db vs. 55db gain with an output of 0.6mv.

If your Melos is providing you with either 54 or 78 db of gain, you could now understand why you are using the lower output setting. A 0.6mv cartridge output would work almost perfectly with your 54db phono gain stage setting as (by the numbers) it would actually require 55db. You are really not going to get any closer than that. BUT, if it is in fact a 0.2mv output, it would also explain why you are experiencing the sound characteristics you described in your original post.

I think now you can see why I use my little calculations/formulae. THEY WORK! It helps to take all of the guess work out of these equations. They allow you to make a more accurate selection of cartridge/phono pre right from the very start or, in the very least, give you a closer approximation of where you need to be. (Measure twice, Cut once)

If you could, recheck your cartridge output. After that has been firmly established, we can then address the capacitance/operation issues.