You mentioned that in your location the smaller Wellbrook ALA 1530 gave
a lower
S-meter reading, but was clearer then your Wellbrook K9AY loop. Is it
posible
the K9AY produces enough RF to cause your receiver to, so to speak,
"fold".

I have found that too much RF, even well removed from the tuned
frequency,
can cause many receivers to act "weird". By wierd I am referring to non
obvious distortion that degrades intelligibility. Me experiments over
the last
~14 months showed me that ANYTHING that degrades the signal to noise
will impair intelligibility.

I found that every receiver I tested, the boring list at the end,
experienced
degraded intelligibility with a long enough wire antenna. Long enough
might
be 50' with the DX398, to 1000' with the R390/R392.

Receivers used:
R2000, R1000, PRC1000,DX398, R390, R392, AOR7030+, R8B and several
ham transceivers with general coverage receivers.

If you have a RF attentuator, in a pinch a the Rat Shack TV adjustable
pad
can be used, could you try an experiment? The next time you encounter a
situation where the ALA 1530 gives better, as in increased
intelligibility, place
the attenuator/pad inline and see if reducing the incoming RF voltage
helps.

Several things I read got me to thinking about the effect of broad band
"noise"
and the effect it could have on cross modulation/IMD/IP2/IP3 at the
first mixer,
before great selectivity is present. IF, please note the IF, the
first mixer
adds unwanted RF crap from unwanted, overly strong, RF "noise", then
intelligibility
will almost certainly suffer.

"Noise" in this context means every RF signal other then the one you
want.

Longer, as in the length of an antenna, is not always better.

Terry