The best passive preamp

Is there balance control with the MLA, or just tight mathcing between channels. I think we might be both of the mind that channel balancing is an important "preamp" function, but most passives don't seem geared up for that.

The MLA can come with a balance control or it is available with dual attenuators which is another method you can use to control balance.

Interesting to hear Roger's changing view of resistors versus transformers, I
wonder what is causing that, but alas, another thread....actually, probably
relevant to the thread. TVC / Resistor and balance control are key choices for
the best passive. I think Roger used to be concerned with bandwidth
limitations with transformers versus resistors, but maybe transformer, or
autoformers, are getting better, who knows. Similar "debate" a Salvatore's site
in the passive line stage section. And then there is technical breakthrough of
"touch-less" LDRS.

Anthony can you explain the MLA a bit. It uses a transformer to act as a buffer of sorts, but resistors to attenuate volume? Am I getting that right?

The purpose of the transformer is to step up the voltage, not to attenuate. The 10k potentiometer or series stepped switch does the attenuating.