Help Choosing Headphone Amp for Audeze LCD-2

Emotiva A-100, $300 and done.

Innerfidelity states 2.4mW into 47ohm to reach 100dB with your speakers, this offers 250mW factory and 8500mW with jumpers!

There’s also the Monoprice tube headphone amp/pre with ESS Sabre DAC, which will give 1000mw, and the soon to be released Monolith headphone amp/pre with dual AKM 4493 DACs & Dual AAA-788 Modules.

Don’t care if you spend $3000, it won’t be worthwhile over these options.  
 
Your headphones are $1000, it’s super silly to spend more on an amp than on your actual headphones. Even if you want to use it as a pre-amp, you don’t need to spend much to get one that sounds good either.

I've experimented with many Headphone/Preamp combos for quite some time now and have settled into the Pass Labs HPA-1 with a Chord Qutest. The Pass is equally at home with Preamp duties as it is with driving headphones. 

I would add the  Sony TA-ZH1ES to your list.  The Sony works great as a pre-amp and has a great DAC and a lot of options for outputs.

The LCD-2 sound good with every amp I've tried them with.  They are very good headphones, but perhaps not resolving enough to point out the shortcomings or highlights of most decent quality headphone amps.  They aren't terribly difficult to drive. 

I auditioned the LCD-4 with it and it was the best headphone / amp combination I have yet heard (not that I've heard them all).  I prefer the Sony over the Oppo HA-1, Schiit Mjolnir, and Auralic Taurus MK II to give an idea of what I have owned to compare it to.  I own the LCD-2, but not the LCD-4.  They're on my wish list.