K-57-K diaphragms measurements and questions

[STL]

I have three complete K-57-K midrange horns (let's call them 11, 22, 33). Here are measurements from them:

I also have two additional diaphragms (let's call them A and i). I placed them in the horn 1 and took the following measurements:

I am hoping that someone can tell me (from these measurements) which diaphragms look good and which ones look bad/suspect? While the first three diaphragms look similar, they all sound different (in level and in tone). I have not listened to the two newest diaphragms (that's A and i) much yet.

[STL]

This is somewhat of a follow-up to this old thread:

http://forums.klipsch.com/forums/t/39263.aspx

(for some reason my link option was greyed out)

[Guest " "]

your config shows a low frequency limit of 5hkz and an upper limit of 20khz.....this is a mid driver so low limit should be 600hz and upper limit should be 5khz

[STL]

The low on the graph is 5Hz not 5kHz -- so this low level sweep covers the operating range of the driver (which I was aware of).

[mungkiman]

Did I miss the question?

[Guest " "]

Did I miss the question?

I think he wants to know why the old ones are higher in impedence than the new ones.....things like fractures in used coil leads and hardening of the diaphragm increases the numbers

[STL]

Did I miss the question?

Here is what I said:

I am hoping that someone can tell me (from these measurements) which diaphragms look good and which ones look bad/suspect? While the first three diaphragms look similar, they all sound different (in level and in tone). I have not listened to the two newest diaphragms (that's A and i) much yet.

I think I might have an explination for the difference (between 11/22/33 and 1A/1i). I know the A and i diaphragms have aluminum formers for the voicecoils, and I believe the 11, 22, and 33 ones are all kapton former units.

That said, I found some notes from testing I did awhile back with a handheld B&K Precision 875 LCR meter (that tests at
1kHz I believe) that makes me wonder if one of the motors is actually bad! I saw Re
values between 23 and 13 ohms and Le values between 1 and almost 2 mH
(when each diaphragm is bolted into the very same K-52-K motor). All five of the voice coils measured about the same
resistance wise, coming in at about 11 ohms, when measured NOT in a motor.
I suspect it has something to do
with where the coil sits when at rest in the gap, but would have
expected there to be a tighter tolerance on this. I could
tell a very distinct volume (and even tone) difference between the 23
and 13 ohm diaphragms -- and both of those are kapton former models!
I also have three different K52K motors and they all seem to sound a
bit different (with low volume testing with no filters) -- can this
normal?