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Hi C,
the file you mentioned is the fruit of a tedious but interesting work, needed to verify some options we were discussing at that time, so no explanations, just measurements.
I totally agree with Casey, if you don't need a microphone capable to manage very high sound pressures, the simple p48 works magnifically (the only drawback is the lenght of the cables, they cannot be longer than, say 15-20m). The low frequency response depends on the value of C, as shown (and the following amplifier input stage).
If I recall well, the "Linkwitz" mod of the PUI5024 is not as easy as the Panasonic WM-61, but probably there is some reference in the group files.
stefano

>I am talking about the low frequency response rather than the whole
>response - but my understanding is that the graphs on Page 4 refer to "V1"
>through "V5", which are all Simple P48.
>
>On Page 6, my understanding was that it was talking about V6 (three-wire)
>and V9 (RCA).

That's correct. I was making the point that all the mics have pretty similar responses. Note that even comparing the LF response only, the regular SP48 is only down less than 2dB at 30Hz... I don't know if you are recording elephant footsteps from a mile away or something, but it's hard to imagine a scenario where you're going to notice that, and it'd be trivial to e.q. if you needed.

Also note that V5 of the regular SP48 which used a 5uF capacitor has nearly equivalent bass to the JLM mod. Not sure if there are any drawbacks to that cap size (besides physical size).

The JLM mod reduces sensitivity, and while that may not reduce SNR on paper, in practice it could mean more noise in a recording if the source is quiet. I built a JLM mod SP48 to mic the"kick" drum sound in my cajon, for example - the high SPL handling was needed to avoid distortion. But i use regular SP48 for everything else.

>and maybe it's worth saying, it
>truly is confusing how many variations and partial explanations there are
>about something that purports to be "simple"...

The mic is simple in form, but not simple to understand (as evidenced by the recent thread on the polarity question). It's also a work in progress; capsules change, new things are tried, etc. This is a DIY mic building forum, not a how-to guide, so until someone writes up a beginner-friendly guide to all things SP48, you'll have to expect to do some googling and consolidation of info. Consider it the price of entry to gain access to the eldritch wisdom.

>Essentially, I have some AOM 5024s. I'd like to use circuitry around them
>to have the best low-frequency response, lowest noise, and smallest part
>count - preferably nothing with additional transistors or taking apart a
>capsule - do you have a sense of where I should be looking?

Unless you are recording loud things: regular SP48, optionally with a 5uF cap and resistor sized according to the documentation. As to what qualifies as "loud", if you're not sure if your sounds will be too loud, describe them and group members can weigh in.

And for the record, "Linkwitz'ing a capsule does not require taking it apart, just cutting and modifying a trace on the back.

-- 
Stefano Simonelli